rpc25519

README

rpc25519: ed25519 based RPC for Go/golang

• Recent News (2025 January 04): (Happy New Year!)

For bulk uploads and downloads, v1.3.0 has streaming support. A stream can have any number of Messages in its sequence, and they can be handled by a single server function.

See example.go and the cli_test.go tests 045, 055, and 065.

The structs Downloader, Uploader, and Bistreamer (both up and downloads) provide support.

• Recent News (2024 December 28): remote cancellation support with context.Context

We recently implemented (in v1.2.0) remote call cancellation based on the standard library's context.Context.

The details:

If the client closes the cancelJobCh that was supplied to a previous SendAndGetReply() call, a cancellation request will be sent to the server.

On the server, the request.HDR.Ctx will be set, having be created by context.WithCancel; so the request.HDR.Ctx.Done() channel can be honored.

Similarly, for traditional net/rpc calls, the Client.Go() and Client.Call() methods will respect the optional octx context and transmit a cancellation request to the server. On the server, the net/rpc methods registered must (naturally) be using the first-parameter ctx form of registration in order to be cancellation aware.

Any client-side blocked calls will return on cancellation. The msg.LocalErr for the []byte oriented Message API will be set. For net/rpc API users, the Client.Go() returned call will have the call.Error set. Users of Client.Call() will see the returned error set.

In all cases, the error will be ErrCancelReqSent if the call was in flight on the server, but will be ErrDone if the original call had not been transmitted yet.

Note that context-based cancellation requires the cooperation of the registered server-side call implementations. Go does not support goroutine cancelation, so the remote methods must implement and honor context awareness in order for the remote cancellation message to have effect.

overview

Motivation: I needed a small, simple, and compact RPC system with modern, strong cryptography for goq. To that end, rpc25519 uses only ed25519 keys for its public-key cryptography. A pre-shared-key layer can also be configured for post-quantum security.

Excitedly, I am delighted to report this package also supports QUIC as a transport. QUIC is very fast even though it is always encrypted. This is due to its 0-RTT design and the mature quic-go implementation of the protocol. QUIC allows a local client and server in the same process to share a UDP port. This feature can be useful for conserving ports and connecting across networks.

After tuning and hardening, the UDP/QUIC versus TCP/TLS decision is not really difficult if the client is new every time. In our measurements, TLS (over TCP) has both better connection latency and better throughput than QUIC (over UDP). QUIC does not get to take advantage of its optimization for 0-RTT re-connection under these circumstances (when the client is new). If you have clients that frequently re-connect after loosing network connectivity, then measure QUIC versus TLS/TCP in your application. Otherwise, for performance, prefer TLS over TCP. The latency of TLS is better and, moreover, the throughput of TLS can be much better (4-5x greater). If client port re-use and conservation is a needed, then QUIC may be your only choice.

The rpc25519 package docs are here.

Benchmarks versus other rpc systems are here: https://github.com/glycerine/rpcx-benchmark

# to install/get started: 
#   *warning: ~/go/bin/{srv,cli,selfy,greenpack} are written
#

 git clone https://github.com/glycerine/greenpack ## pre-req
 cd greenpack; make; cd ..
 git clone https://github.com/glycerine/rpc25519
 cd rpc25519;  make
 
 # make test keys and CA: saved to certs/ and my-keep-private-dir/
 ./selfy -k client -nopass; ./selfy -k node -nopass 
 ./selfy -gensym psk.binary ## saved to my-keep-private-dir/psk.binary
 make run && make runq  ## verify TLS over TCP and QUIC
 

For getting started, see the small example programs here: https://github.com/glycerine/rpc25519/tree/master/cmd . These illustrate client (cli), server (srv), and QUIC port sharing by a client and a server (samesame). The tests in srv_test.go and cli_test.go also make great starting points.

overview

rpc25519 is a Remote Procedure Call (RPC) system with two APIs.

We offer both a traditional net/rpc style API, and a generic []byte oriented API for carrying user typed or self describing []byte payloads (in Message.JobSerz).

As of v1.1.0, the net/rpc API has been updated to use greenpack encoding rather than gob encoding, to provide a self-describing, evolvable serialization format. Greenpack allows fields to be added or deprecated over time and is multi-language compatible. We re-used net/rpc's client-facing API layer, and wired it into/on top of our native []byte slice Message transport infrastructure. (The LICENSE file reflects this code re-use.) Instead of taking any struct, arguments and responses must now have greenpack generated methods. Typically this means adding //go:generate greenpack to the files that define the structs that will go over the wire, and running go generate.

rpc25519 was built originally for the distributed job management use-case, and so uses TLS/QUIC directly. It does not use http, except perhaps in the very first contact: like net/rpc, there is limited support for http CONNECT based hijacking; see the cfg.HTTPConnectRequired flag. Nonetheless, this protocol remains distinct from http. In particular, note that the connection hijacking does not work with (https/http2/http3) encrypted protocols.

The generic byte-slice API is designed to work smoothly with our greenpack serialization format that requires no extra IDL file. See the https://github.com/glycerine/rpc25519/blob/master/hdr.go#L18 file herein, for example.

Using the rpc25519.Message based API:

• Server.Register1Func() registers one-way (no reply) callbacks on the server. They look like this:

  func ExampleOneWayFunc(req *Message) { ... }

• Server.Register2Func() registers traditional two-way callbacks. They look like this:

  func ExampleTwoWayFunc(req *Message, reply *Message) error { ... }

The central Message struct itself is simple.

  type Message struct {

   // HDR contains header information. See hdr.go.
   HDR HDR `zid:"0"`

   // JobSerz is the "body" of the message.
   // The user provides and interprets this.
   JobSerz []byte `zid:"1"`

   // JobErrs returns error information from 
   // user-defined callback functions. If a 
   // TwoWayFunc returns a non-nil error, its
   // err.Error() will be set here.
   JobErrs string `zid:"2"`

   // LocalErr is not serialized on the wire.
   // It communicates only local (client/server side) 
   // API information. For example, Server.SendMessage() or
   // Client.SendAndGetReply() can read it after
   // DoneCh has been received on.
   //
   // Callback functions should convey 
   // errors in JobErrs (by returning an error); 
   // or in-band within JobSerz.
   LocalErr error `msg:"-"`

   // DoneCh will receive this Message itself when the call completes.
   // It must be buffered, with at least capacity 1.
   // NewMessage() automatically allocates DoneCh correctly and
   // should always be used when creating a new Message.
   DoneCh chan *Message `msg:"-"`
}

Using the net/rpc API:

• Server.Register() registers structs with callback methods on them. For a struct called Service, this method would be identified and registered:

  func (s *Service) NoContext(args *Args, reply *Reply) error { ... }

See the net/rpc docs for full guidance on using that API.

• Extended method types:

Callback methods in the net/rpc style traditionally look like the NoContext method above. We also allow a ctx context.Context as an additional first parameter. This is an extension to what net/rpc provides. The ctx will have an "HDR" value set on it giving a pointer to the rpc25519.HDR header from the incoming Message.

func (s *Service) GetsContext(ctx context.Context, args *Args, reply *Reply) error {
   if hdr, ok := rpc25519.HDRFromContext(ctx); ok {
        fmt.Printf("GetsContext called with HDR = '%v'; "+
           "HDR.Nc.RemoteAddr() gives '%v'; HDR.Nc.LocalAddr() gives '%v'\n", 
           hdr.String(), hdr.Nc.RemoteAddr(), hdr.Nc.LocalAddr())
   } else {
      fmt.Println("HDR not found")
   }
   ...
   return nil
}

The net/rpc API is implemented as a layer on top of the rpc25519.Message based API. Both can be used concurrently if desired.

In the Message API, server push is available. Use Client.GetReadIncomingCh or Client.GetReads on the client side to receive server initiated messages. To push from the server (in a callback func), see Server.SendMessage. An live application example of server push is here, in the ServerCallbackMgr.pushToClient() method.

See the full source for my distributed job-queuing server goq as an example application that uses most all features of this, the rpc25519 package.

In the following we'll look at choice of transport, why public-key certs are preferred, and how to use the included selfy tool to easily generate self-signed certificates.

TLS-v1.3 over TCP

Three transports are available: TLS-v1.3 over TCP, plain TCP, and QUIC which uses TLS-v1.3 over UDP.

How to KYC or Know Your Clients

How do we identify our clients in an RPC situation?

We have clients and servers in RPC. For that matter, how do we authenticate the server too?

The identity of an both client and server, either end of a connection, is established with a private-key/public-key pair in which the remote party proves posession of a private-key and we can confirm that the associated public-key has been signed by our certificate authority. Public keys signed in this way are more commonly called certificates or "certs".

An email address for convenience in identifying jobs can be listed in the certificate.

This is a much saner approach than tying a work-load identity to a specific machine, domain name, or machine port. Access to the private key corresponding to our cert should convey identity during a TLS handshake. The later part of the handshake verifies that the key was signed by our CA. This suffices. We may also want to reject based on IP address to block off clearly irrelevant traffic; both to for DDos mitigation and to keep our CPU cycles low, but these are second order optimizations. The crytographic proof is the central identifying factor.

Such a requirement maintains the strongest security but still allows elastic clouds to grow and shrink and migrate the workloads of both clients and servers. It allows for sane development and deployment on any hardware a developer can access with ssh, without compromising on encryption on either end.

TOFU or not

By creating (touch will do) a known_client_keys file on the server directory where the server is running, you activate the key tracking system on the server.

Similarly, by touching the known_server_keys file in the directory where the client is running, you tell the client to record the server certificates it has seen.

Without these files, no history of seen certs is recorded. While certs are still checked (assuming you have left SkipVerifyKeys at the default false value in the config), they are not remembered.

In a typical use case, touch the file to record the certs in use, then make the known keys file read-only to block out any new certs.

This works because clients are accepted or rejected depending on the writability of the known_client_keys file, and the presence of their certificates in that file.

Trust on first use, or TOFU, is used if the known_client_keys file is writable. When the file is writable and a new client arrives, their public key and email (if available) are stored. This is similar to how the classic ~/.ssh/known_hosts file works, but with a twist.

The twist is that once the desired identities have been recorded, the file can be used to reject any new or unknown certs from new or unkown clients.

If the file has been made unwritable (say with chmod -w known_client_keys), then we are "locked down". In this case, TOFU is not allowed and only existing keys will be accepted. Any others whose public keys are not in the known_client_hosts file will be dropped during the TLS handshake.

These unknown clients are usually just attackers that should in fact be rejected soundly. In case of misconfiguration however, all clients should be prepared to timeout as, if they are not on the list, they will be shunned and shown no further attention or packets. Without a timeout, they may well hang indefinitely waiting for network activity.

encryption details

Modern Ed25519 keys are used with TLS-1.3. The TLS_CHACHA20_POLY1305_SHA256 cipher suite is the only one configured. This is similar to the crypto suite used in Wireguard (TailScale), the only difference being that Wireguard uses Blake2s as a hash function (apparently faster than SHA-256 when hardware support SHA-extensions/SHA-NI instructions are not available). The ChaCha20, Poly1305, and Curve25519 parts are the same.

Config.PreSharedKeyPath allows specifying a 32 byte pre-shared key file for further security. An additional, independently keyed layer of ChaCha20-Poly1305 stream cipher/AEAD will be applied by mixing that key into the shared secret from an ephemeral Elliptic Curve Diffie-Hellman handshake. The same pre-shared-key must be pre-installed on both client and server.

The pre-shared-key traffic is "tunnelled" or runs inside the outer encryption layer. Thus a different symmetric encryption scheme could be wired in without much difficulty.

The pre-shared-key file format is just raw random binary bytes. See the srv_test.go Test011_PreSharedKey_over_TCP test in https://github.com/glycerine/rpc25519/blob/master/srv_test.go#L297 for an example of using NewChaCha20CryptoRandKey() to generate a key programmatically. Or just use

selfy -gensym my_pre_shared_key.binary

on the command line. For safety, selfy -gensym will not over-write an existing file. If you want to change keys, mv the old key out of the way first.

security posture for both extremes

The strength of security is controlled by the Config options to NewServer() and NewClient(). This section was written before we added the second symmetric encryption by pre-shared key option. All comments below about lack of security (e.g. in TCPonly_no_TLS = true mode) should be read modulo the pre-shared-key stuff: assume there is no 2nd layer.

See the cli.go file and the Config struct there; also copied below.

By default security is very strong, requiring TLS-1.3 and valid signed client certs, but allowing TOFU for previously unseen clients who come bearing valid certs; those signed by our CA.

This allows one to test one's initial setup with a minimum of fuss.

Further hardening (into a virtual fortress) can then be accomplished by making read-only the set of already seen clients; with chmod -w known_client_keys.

With this done, only those clients who we have already seen will be permitted in; and these are clients bearing proper certs signed by our CA private key; this will be verified during the TLS handshake. Any others will be rejected.

On the other extreme, setting TCPonly_no_TLS to true means we will use only TCP, no TLS at all, and everything will be transmitted in clear text.

In the middle of the road, setting Config.SkipVerifyKeys to true means the server will act like an HTTPS web server: any client with any key will be allowed to talk to the server, but TLS-1.3 will encrypt the traffic. Whenever TLS is used, it is always TLS-1.3 and set to the tls.TLS_CHACHA20_POLY1305_SHA256 cipher suite. Thus this setting is of no use for authenticating clients; it should almost never be used since it opens up your server to the world. But for web servers, this may be desirable.

Note that both sides of the connection (client and server) must agree to -skip-verify (Config.SkipVerifyKeys = true); otherwise the signing authority (CA) must agree. Under the default, SkipVerifyKeys = false, by signing only your own keys, with your own CA, that you keep private from the world, you maintain very tight control over access to your server.

We only create and only accept Ed25519 keys (with SkipVerifyKeys off/false, the default). (See selfy below, or the included gen.sh script to create keys).

type Config struct {

   // ServerAddr host:port where the server should listen.
   ServerAddr string

   // optional. Can be used to suggest that the
   // client use a specific host:port. NB: For QUIC, by default, the client and
   // server will share the same port if they are in the same process.
   // In that case this setting will definitely be ignored.
   ClientHostPort string

   // Who the client should contact
   ClientDialToHostPort string

   // TCP false means TLS-1.3 secured. 
   // So true here means do TCP only; with no encryption.
   TCPonly_no_TLS bool

   // UseQUIC cannot be true if TCPonly_no_TLS is true.
   UseQUIC bool

   // path to certs/ like certificate
   // directory on the live filesystem.
   CertPath string

   // SkipVerifyKeys true allows any incoming
   // key to be signed by
   // any CA; it does not have to be ours. Obviously
   // this discards almost all access control; it
   // should rarely be used unless communication
   // with the any random agent/hacker/public person
   // is desired.
   SkipVerifyKeys bool

   // default "client" means use certs/client.crt and certs/client.key
   ClientKeyPairName string 
   
   // default "node" means use certs/node.crt and certs/node.key
   ServerKeyPairName string 

   // PreSharedKeyPath locates an optional pre-shared
   // binary that  must be 32 bytes long.
   // If supplied, this key will be used in a symmetric 
   // encryption layer inside the outer TLS encryption.
   PreSharedKeyPath string

   // These are timeouts for connection and transport tuning.
   // The defaults of 0 mean wait forever.
   ConnectTimeout time.Duration
   ReadTimeout    time.Duration
   WriteTimeout   time.Duration

   ...
   
   // This is not a Config option, but creating
   // the known_{server,client}_keys file on the client/server is
   // typically the last security measure in hardening.
   //
   // If known_client_keys exists in the server's directory,
   // then we will read from it.
   // Likewise, if known_server_keys exists in
   // the client's directory, then we will read from it.
   //
   // If the known keys file is read-only: Read-only
   // means we are in lockdown mode and no unknown
   // client certs will be accepted, even if they
   // have been properly signed by our CA.
   //
   // If the known keys file is writable then we are
   // Trust On First Use mode, and new remote parties
   // are recorded in the file if their certs are valid (signed
   // by us/our CA).
   //
   // Note if the known_client_keys is read-only, it
   // had better not be empty or nobody will be
   // able to contact us. The server will notice
   // this and crash since why bother being up.
   
}

The selfy tool: create new keys quickly; view certificates

Certificates are great, but making them has traditionally been a massive pain. That is why I wrote selfy.

The selfy command is an easy way to create private keys, certificates, and self-signed certficate authories. It is vastly more usable than the mountain of complexity that is openssl. It is more limited in scope. In our opinion, this a good thing.

If you are in a hurry to get started, the most basic use of selfy is to create a new ed25519 key-pair:

$ selfy -k name_of_your_identity -e your@email.here.org

With other tools you would need to already have a CA (Certificate Authority).

But we've got your back. If you lack a CA in the default directory (see -p below), then, for your convenience, a self-signed CA will be auto-generated for you. It will then be used to sign the new cert. Hence the above command is all that a typical developer needs to get started. Yay(!)

If you want to first create a CA manually, you can do that with the -ca flag. The -p flag will let you put it somewhere other than the default directory.

selfy -ca # make a new self-signed Certificate Authority

Your newly created cert can be viewed with the selfy -v flag, just give it the path to your .crt file.

$ selfy -v certs/name_of_your_identity.crt

By default, the CA is stored in the ./my-keep-private-dir/ca.{crt,key}, while the -k named identifying cert is stored in certs/name.crt. The corresponding private key is stored in certs/name.key.

Update: we have added pass-phrase protection to the private keys by default. In order to forgo this protection and use the original behavior, supply the selfy --nopass flag. A long salt and the Argon2id key-derivation-function are used to provide time and memory-hard protection against ASIC brute-force cracking attempts (see https://en.wikipedia.org/wiki/Argon2 https://datatracker.ietf.org/doc/html/rfc9106 ).

$ selfy -h

Usage of selfy:
  -ca
        create a new self-signed certificate authority (1st of 2 
        steps in making new certs). Written to the -p directory 
        (see selfy -p flag, where -p is for private).
        The CA uses ed25519 keys too.
        
  -e string
        email to write into the certificate (who to contact 
        about this job) (strongly encouraged when making 
        new certs! defaults to name@host if not given)
    
  -gensym string
        generate a new 32-byte symmetric encryption 
        key with crypto/rand, and save it under 
        this filename in the -p directory.
    
  -k string
        2nd of 2 steps: -k {key_name} ; create a new ed25519 
        key pair (key and cert), and save it to this name. 
        The pair will be saved under the -o directory; 
        we strongly suggest you also use the 
        -e your_email@actually.org flag to 
        describe the job and/or provide the owner's email 
        to contact when needed. A CA will be auto-generated 
        if none is found in the -p directory, which has 
        a default name which warns the user to protect it.

  -nopass
        by default we request a password and use 
        it with Argon2id to encrypt private key files (CA & identity). 
        Setting -nopass means we generate an un-encrypted 
        private key; this is not recommended.

  -o string
        directory to save newly created certs into. (default "certs")
        
  -p string
        directory to find the CA in. If doing -ca, we will save 
        the newly created Certificate Authority (CA) private 
        key to this directory. If doing -k to create a new key, 
        we'll look for the CA here. (default "my-keep-private-dir")  
        
  -v string
        path to cert to view. Similar output as the openssl 
        command: 'openssl x509 -in certs/client.crt  -text -noout', 
        which you could use instead; just replace certs/client.crt 
        with the path to your cert.

  -verify string
        verify this path is a certificate signed by the private key 
        corresponding to the -p {my-keep-private-dir}/ca.crt public key

The openssl commands in the included gen.sh script do the same things as selfy does, but it is more painful to incorporate an email because you have to modify the openssl-san.cnf file to do so each time.

generating keys with emails inside

See the selfy -e flag above for details.

Delightfully, email addresses can be stored in certificates!

This provides a fantastically convenient way to identify the job and/or the owner of the job. Importantly, if you are supporting work loads from many people, this can be critical in telling who needs to know when something goes wrong with a job.

A localhost by any other name would not smell as sweet

The server name will always be 'localhost' on selfy generated certificates, and this is critical to allowing our processes to run on any machine. By doing so, we leverage the SNI technology[1], to break the troublesome adhesion of IP address and certificate. SNI was developed to let a single IP address host many different web sites. We want multiple IP addresses to run many different jobs, and to be able to migrate jobs between hosts. Brilliantly, SNI lets us move our clients and servers between machines without having to re-issue the certificates. The certs are always issued to 'localhost' and clients always request ServerName 'localhost' in their tls.Config.ServerName field.

This is much more like the convenience and usability ssh. To me ssh has always been so much easier to deal with than certificates. rpc25519 aims for usability on par with ssh. Leveraging SNI is one way we get there.

[1] https://en.wikipedia.org/wiki/Server_Name_Indication ,

---

Author: Jason E. Aten, Ph.D.

License: See the LICENSE file for the 3-clause BSD-style license; the same as Go.

Documentation

Index

• Constants
• Variables
• func ContextWithHDR(ctx context.Context, hdr *HDR) context.Context
• func GoroNumber() int
• func IsNil(face interface{}) bool
• func MinimalBistreamFunc(srv *Server, ctx context.Context, req *Message, ...) (err error)
• func NewCallID() string
• func NewChaCha20CryptoRandKey() []byte
• func SelfyNewKey(createKeyPairNamed, odir string) error
• type Args
  • func (z *Args) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z Args) EncodeMsg(en *msgp.Writer) (err error)
  • func (z Args) MarshalMsg(b []byte) (o []byte, err error)
  • func (z Args) Msgsize() (s int)
  • func (z *Args) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *Args) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type Arith
  • func (t *Arith) Add(args Args, reply *Reply) error
  • func (z *Arith) DecodeMsg(dc *msgp.Reader) (err error)
  • func (t *Arith) Div(args Args, reply *Reply) error
  • func (z Arith) EncodeMsg(en *msgp.Writer) (err error)
  • func (t *Arith) Error(args *Args, reply *Reply) error
  • func (z Arith) MarshalMsg(b []byte) (o []byte, err error)
  • func (z Arith) Msgsize() (s int)
  • func (t *Arith) Mul(args *Args, reply *Reply) error
  • func (t *Arith) Scan(args string, reply *Reply) (err error)
  • func (t *Arith) SleepMilli(args *Args, reply *Reply) error
  • func (t *Arith) String(args *Args, reply *string) error
  • func (z *Arith) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *Arith) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type BenchmarkMessage
  • func (z *BenchmarkMessage) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z *BenchmarkMessage) EncodeMsg(en *msgp.Writer) (err error)
  • func (z *BenchmarkMessage) MarshalMsg(b []byte) (o []byte, err error)
  • func (z *BenchmarkMessage) Msgsize() (s int)
  • func (z *BenchmarkMessage) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *BenchmarkMessage) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type BistreamFunc
• type Bistreamer
  • func (s *Bistreamer) CallID() string
  • func (s *Bistreamer) UploadMore(ctx context.Context, msg *Message, last bool) (err error)
• type BuiltinTypes
  • func (BuiltinTypes) Array(args *Args, reply *[2]int) error
  • func (z *BuiltinTypes) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z BuiltinTypes) EncodeMsg(en *msgp.Writer) (err error)
  • func (BuiltinTypes) Map(args *Args, reply *map[int]int) error
  • func (z BuiltinTypes) MarshalMsg(b []byte) (o []byte, err error)
  • func (z BuiltinTypes) Msgsize() (s int)
  • func (BuiltinTypes) Slice(args *Args, reply *[]int) error
  • func (z *BuiltinTypes) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *BuiltinTypes) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
  • func (BuiltinTypes) WantsContext(ctx context.Context, args *Args, reply *[2]int) error
• type Call
• type CallType
  • func (z *CallType) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z CallType) EncodeMsg(en *msgp.Writer) (err error)
  • func (z CallType) MarshalMsg(b []byte) (o []byte, err error)
  • func (z CallType) Msgsize() (s int)
  • func (ct CallType) String() string
  • func (z *CallType) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *CallType) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type Client
  • func NewClient(name string, config *Config) (c *Client, err error)
  • func (c *Client) Call(serviceMethod string, args, reply Green, octx context.Context) error
  • func (c *Client) Close() error
  • func (c *Client) Err() error
  • func (c *Client) GetOneRead(seqno uint64, ch chan *Message)
  • func (c *Client) GetReadIncomingCh() (ch chan *Message)
  • func (c *Client) GetReadIncomingChForCallID(callID string) (ch chan *Message)
  • func (c *Client) GetReads(ch chan *Message)
  • func (c *Client) GetReadsForCallID(ch chan *Message, callID string)
  • func (c *Client) Go(serviceMethod string, args Green, reply Green, done chan *Call, ...) *Call
  • func (c *Client) IsDown() (down bool)
  • func (c *Client) LocalAddr() string
  • func (c *Client) Name() string
  • func (c *Client) OneWaySend(msg *Message, cancelJobCh <-chan struct{}) (err error)
  • func (c *Client) RequestBistreaming(ctx context.Context, bistreamerName string, req *Message) (b *Bistreamer, err error)
  • func (c *Client) RequestDownload(ctx context.Context, streamerName string) (downloader *Downloader, err error)
  • func (c *Client) SendAndGetReply(req *Message, cancelJobCh <-chan struct{}) (reply *Message, err error)
  • func (c *Client) SendAndGetReplyWithCtx(ctx context.Context, req *Message) (reply *Message, err error)
  • func (c *Client) SendAndGetReplyWithTimeout(timeout time.Duration, req *Message) (reply *Message, err error)
  • func (c *Client) Start() error
  • func (c *Client) UngetReads(ch chan *Message)
  • func (c *Client) UploadBegin(ctx context.Context, msg *Message) (strm *Uploader, err error)
• type ClientCodec
• type Config
  • func NewConfig() *Config
  • func (cfg *Config) Clone() *Config
• type Downloader
• type Embed
  • func (z *Embed) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z Embed) EncodeMsg(en *msgp.Writer) (err error)
  • func (z Embed) MarshalMsg(b []byte) (o []byte, err error)
  • func (z Embed) Msgsize() (s int)
  • func (z *Embed) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *Embed) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type Green
• type HDR
  • func HDRFromBytes(jsonData []byte) (*HDR, error)
  • func HDRFromContext(ctx context.Context) (*HDR, bool)
  • func HDRFromGreenpack(header []byte) (*HDR, error)
  • func NewHDR(from, to, subject string, typ CallType, streamPart int64) (m *HDR)
  • func Unbytes(jsonData []byte) *HDR
  • func (hdr *HDR) AsGreenpack(scratch []byte) (o []byte, err error)
  • func (m *HDR) Bytes() []byte
  • func (m *HDR) Compact() string
  • func (z *HDR) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z *HDR) EncodeMsg(en *msgp.Writer) (err error)
  • func (a *HDR) Equal(b *HDR) bool
  • func (m *HDR) JSON() []byte
  • func (z *HDR) MarshalMsg(b []byte) (o []byte, err error)
  • func (z *HDR) Msgsize() (s int)
  • func (m *HDR) Pretty() string
  • func (m *HDR) String() string
  • func (z *HDR) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *HDR) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type Hello
  • func (z *Hello) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z Hello) EncodeMsg(en *msgp.Writer) (err error)
  • func (z Hello) MarshalMsg(b []byte) (o []byte, err error)
  • func (z Hello) Msgsize() (s int)
  • func (z *Hello) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *Hello) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type InvalidRequest
  • func (z *InvalidRequest) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z InvalidRequest) EncodeMsg(en *msgp.Writer) (err error)
  • func (z InvalidRequest) MarshalMsg(b []byte) (o []byte, err error)
  • func (z InvalidRequest) Msgsize() (s int)
  • func (z *InvalidRequest) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *InvalidRequest) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type Message
  • func MessageFromGreenpack(by []byte) (*Message, error)
  • func NewMessage() *Message
  • func NewMessageFromBytes(by []byte) (msg *Message)
  • func (m *Message) AsGreenpack(scratch []byte) (o []byte, err error)
  • func (m *Message) AsJSON(scratch []byte) (o []byte, err error)
  • func (z *Message) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z *Message) EncodeMsg(en *msgp.Writer) (err error)
  • func (z *Message) MarshalMsg(b []byte) (o []byte, err error)
  • func (z *Message) Msgsize() (s int)
  • func (msg *Message) String() string
  • func (z *Message) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *Message) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type MustBeCancelled
  • func NewMustBeCancelled() *MustBeCancelled
  • func (z *MustBeCancelled) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z MustBeCancelled) EncodeMsg(en *msgp.Writer) (err error)
  • func (z MustBeCancelled) MarshalMsg(b []byte) (o []byte, err error)
  • func (s *MustBeCancelled) MessageAPI_HangUntilCancel(req, reply *Message) error
  • func (z MustBeCancelled) Msgsize() (s int)
  • func (z *MustBeCancelled) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *MustBeCancelled) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
  • func (s *MustBeCancelled) WillHangUntilCancel(ctx context.Context, args *Args, reply *Reply) error
• type NetConnWrapper
  • func (w *NetConnWrapper) Close() error
• type OneWayFunc
• type Reply
  • func (z *Reply) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z Reply) EncodeMsg(en *msgp.Writer) (err error)
  • func (z Reply) MarshalMsg(b []byte) (o []byte, err error)
  • func (z Reply) Msgsize() (s int)
  • func (z *Reply) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *Reply) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type Request
  • func (z *Request) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z Request) EncodeMsg(en *msgp.Writer) (err error)
  • func (z Request) MarshalMsg(b []byte) (o []byte, err error)
  • func (z Request) Msgsize() (s int)
  • func (z *Request) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *Request) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type Response
  • func (z *Response) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z Response) EncodeMsg(en *msgp.Writer) (err error)
  • func (z Response) MarshalMsg(b []byte) (o []byte, err error)
  • func (z Response) Msgsize() (s int)
  • func (z *Response) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *Response) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type ServeBistreamState
  • func (bi *ServeBistreamState) ServeBistream(srv *Server, ctx context.Context, req *Message, ...) (err error)
• type Server
  • func NewServer(name string, config *Config) *Server
  • func (s *Server) Close() error
  • func (s *Server) Register(rcvr msgp.Encodable) error
  • func (s *Server) Register1Func(callme1 OneWayFunc)
  • func (s *Server) Register2Func(callme2 TwoWayFunc)
  • func (s *Server) RegisterBistreamFunc(name string, callme BistreamFunc)
  • func (s *Server) RegisterName(name string, rcvr msgp.Encodable) error
  • func (s *Server) RegisterServerSendsDownloadFunc(name string, callme ServerSendsDownloadFunc)
  • func (s *Server) RegisterUploadReaderFunc(callmeUploadReader UploadReaderFunc)
  • func (s *Server) SendMessage(callID, subject, destAddr string, data []byte, seqno uint64, ...) error
  • func (s *Server) SendOneWayMessage(ctx context.Context, msg *Message, errWriteDur *time.Duration) error
  • func (server *Server) ServeHTTP(w http.ResponseWriter, req *http.Request)
  • func (s *Server) Start() (serverAddr net.Addr, err error)
• type ServerClient
• type ServerCodec
• type ServerError
  • func (e ServerError) Error() string
• type ServerSendsDownloadFunc
• type ServerSendsDownloadState
  • func (ssss *ServerSendsDownloadState) ServerSendsDownload(srv *Server, ctx context.Context, req *Message, ...) (err error)
• type ServerSideUploadState
  • func NewServerSideUploadState() *ServerSideUploadState
  • func (s *ServerSideUploadState) ReceiveFileInParts(req *Message, lastReply *Message) (err error)
• type Simple
  • func (z *Simple) DecodeMsg(dc *msgp.Reader) (err error)
  • func (z Simple) EncodeMsg(en *msgp.Writer) (err error)
  • func (t *Simple) Exported(args Args, reply *Reply) error
  • func (z Simple) MarshalMsg(b []byte) (o []byte, err error)
  • func (z Simple) Msgsize() (s int)
  • func (z *Simple) UnmarshalMsg(bts []byte) (o []byte, err error)
  • func (z *Simple) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)
• type TwoWayFunc
• type UploadReaderFunc
• type Uploader
  • func (s *Uploader) CallID() string
  • func (s *Uploader) UploadMore(ctx context.Context, msg *Message, last bool) (err error)

Constants

const (
	// Defaults used by HandleHTTP
	DefaultRPCPath = "/_goRPC_"
)

const (
	UserMaxPayload = 67106000 // users should chunk to this size, to be safe.
)

Variables

var ErrAlreadyDone = fmt.Errorf("Uploader has already been marked done. No more sending is allowed.")

var ErrCancelReqSent = fmt.Errorf("cancellation request sent")

var ErrContextCancelled = fmt.Errorf("context cancelled")

var ErrDone = fmt.Errorf("done channel closed")

var ErrHandshakeQUIC = fmt.Errorf("quic handshake failure")

var ErrMagicWrong = fmt.Errorf("error: magic bytes not found at start of message")

var ErrNetConnectionNotFound = fmt.Errorf("error in SendMessage: net.Conn not found")

var ErrNetRpcShutdown = errors.New("connection is shut down")

ErrNetRpcShutdown is from net/rpc, and still distinct from ErrShutdown to help locate when and where the error was generated. It indicates the system, or at least the network connection or stream, is closed or shutting down.

var ErrNotFound = fmt.Errorf("known_tls_hosts file not found")

var ErrShutdown = fmt.Errorf("shutting down")

var ErrTimeout = fmt.Errorf("time-out waiting for call to complete")

var ErrTooLarge = fmt.Errorf("error: length of payload JobSerz is over maxMessage - 1024(for header) = %v bytes, which is the limit.", maxMessage-1024)

var ErrTooLong = fmt.Errorf("message message too long: over 64MB; encrypted client vs an un-encrypted server?")

var ErrWrongCallTypeForSendMessage = fmt.Errorf("error in SendMessage: msg.HDR.Typ must be CallOneWay or CallUploadBegin; or greater in number")

Functions

func ContextWithHDR

func ContextWithHDR(ctx context.Context, hdr *HDR) context.Context

ContextWithHDR returns a new Context that carries value hdr.

func GoroNumber

func GoroNumber() int

GoroNumber returns the calling goroutine's number.

func IsNil

func IsNil(face interface{}) bool

IsNil uses reflect to to return true iff the face contains a nil pointer, map, array, slice, or channel.

func MinimalBistreamFunc

func MinimalBistreamFunc(
	srv *Server,
	ctx context.Context,
	req *Message,
	uploadsFromClientCh <-chan *Message,
	sendDownloadPartToClient func(ctx context.Context, by []byte, last bool),
	lastReply *Message,
) (err error)

MinimalBistreamFunc stands in contract to the fleshed on ServeBistream example above. It attempts to illustrate only the bare minimal needed to implement a BistreamFunc, so the user can glimpse its conceptual elegance.

It provides a starter template for writing your own.

Typically you might want to make it a method on a struct that provides it with other application dependent state and helper methods. But that's not minimal.

func NewCallID

func NewCallID() string

func NewChaCha20CryptoRandKey

func NewChaCha20CryptoRandKey() []byte

func SelfyNewKey

func SelfyNewKey(createKeyPairNamed, odir string) error

SelfyNewKey is only for testing, not production. It is used by the tests to check that certs are signed by the expected CA.

SelfyNewKey will generate a self-signed certificate authority, a new ed25519 key pair, sign the public key to create a cert, and write these four new files to disk. The directories odir/my-keep-private-dir and odir/certs will be created, based on the odir argument. For a given createKeyPairNamed name, we will create odir/certs/name.crt and odir/certs/name.key files. The odir/certs/name.key and my-keep-private-dir/ca.key files contain private keys and should be kept confidential. The `selfy` command in this package can be used to produce the same keys but with password protection, which is recommended.

Types

type Args

type Args struct {
	A int `zid:"0"`
	B int `zid:"1"`
}

Args in example.go is part of the tests.

func (*Args) DecodeMsg

func (z *Args) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (Args) EncodeMsg

func (z Args) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (Args) MarshalMsg

func (z Args) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (Args) Msgsize

func (z Args) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*Args) UnmarshalMsg

func (z *Args) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*Args) UnmarshalMsgWithCfg

func (z *Args) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type Arith

type Arith int

Arith in example.go is part of the tests.

func (*Arith) Add

func (t *Arith) Add(args Args, reply *Reply) error

Arith.Add in example.go is part of the tests.

func (*Arith) DecodeMsg

func (z *Arith) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (*Arith) Div

func (t *Arith) Div(args Args, reply *Reply) error

Arith.Div in example.go is part of the tests.

func (Arith) EncodeMsg

func (z Arith) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (*Arith) Error

func (t *Arith) Error(args *Args, reply *Reply) error

Arith.Error in example.go is part of the tests.

func (Arith) MarshalMsg

func (z Arith) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (Arith) Msgsize

func (z Arith) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*Arith) Mul

func (t *Arith) Mul(args *Args, reply *Reply) error

Arith.Mul in example.go is part of the tests.

func (*Arith) Scan

func (t *Arith) Scan(args string, reply *Reply) (err error)

Arith.Scan in example.go is part of the tests.

func (*Arith) SleepMilli

func (t *Arith) SleepMilli(args *Args, reply *Reply) error

Arith.SleepMilli in example.go is part of the tests.

func (*Arith) String

func (t *Arith) String(args *Args, reply *string) error

Arith.String in example.go is part of the tests.

func (*Arith) UnmarshalMsg

func (z *Arith) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*Arith) UnmarshalMsgWithCfg

func (z *Arith) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type BenchmarkMessage

type BenchmarkMessage struct {
	Field1   string   `zid:"0"`
	Field9   string   `zid:"1"`
	Field18  string   `zid:"2"`
	Field80  bool     `zid:"3"`
	Field81  bool     `zid:"4"`
	Field2   int32    `zid:"5"`
	Field3   int32    `zid:"6"`
	Field280 int32    `zid:"7"`
	Field6   int32    `zid:"8"`
	Field22  int64    `zid:"9"`
	Field4   string   `zid:"10"`
	Field5   []uint64 `zid:"11"`
	Field59  bool     `zid:"12"`
	Field7   string   `zid:"13"`
	Field16  int32    `zid:"14"`
	Field130 int32    `zid:"15"`
	Field12  bool     `zid:"16"`
	Field17  bool     `zid:"17"`
	Field13  bool     `zid:"18"`
	Field14  bool     `zid:"19"`
	Field104 int32    `zid:"20"`
	Field100 int32    `zid:"21"`
	Field101 int32    `zid:"22"`
	Field102 string   `zid:"23"`
	Field103 string   `zid:"24"`
	Field29  int32    `zid:"25"`
	Field30  bool     `zid:"26"`
	Field60  int32    `zid:"27"`
	Field271 int32    `zid:"28"`
	Field272 int32    `zid:"29"`
	Field150 int32    `zid:"30"`
	Field23  int32    `zid:"31"`
	Field24  bool     `zid:"32"`
	Field25  int32    `zid:"33"`
	Field78  bool     `zid:"34"`
	Field67  int32    `zid:"35"`
	Field68  int32    `zid:"36"`
	Field128 int32    `zid:"37"`
	Field129 string   `zid:"38"`
	Field131 int32    `zid:"39"`
}

BenchmarkMessage in example.go is part of the tests and benchmarks.

func (*BenchmarkMessage) DecodeMsg

func (z *BenchmarkMessage) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (*BenchmarkMessage) EncodeMsg

func (z *BenchmarkMessage) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (*BenchmarkMessage) MarshalMsg

func (z *BenchmarkMessage) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (*BenchmarkMessage) Msgsize

func (z *BenchmarkMessage) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*BenchmarkMessage) UnmarshalMsg

func (z *BenchmarkMessage) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*BenchmarkMessage) UnmarshalMsgWithCfg

func (z *BenchmarkMessage) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type BistreamFunc

type BistreamFunc func(
	srv *Server,
	ctx context.Context,
	req *Message,
	uploadsFromClientCh <-chan *Message,
	sendDownloadPartToClient func(ctx context.Context, by []byte, last bool),
	lastReply *Message,
) (err error)

BistreamFunc aims to allow the user to implement server operations with full generality; it provies for uploads and downloads to the originating client, and for communication with other clients. Use Server.RegisterBistreamFunc() to register your BistreamFunc under a name. The BistreamFunc and its siblings the ServerSendsDownloadFunc and the UploadReaderFunc are only available for the Message based API; not in the net/rpc API.

On the client side, the Client.RequestBistreaming() call is used to create a Bistreamer that will call the BistreamFunc by its registered name (the name that Server.RegisterBistreamFunc() was called with).

In a BistreamFunc on the server, the full generality of interleaving upload and download handling is available. The initial Message in req will also be the first Message in the req.HDR.UploadsCh which receives all upload messages from the client.

To note, it may be more convenient for the user to use an UploadReaderFunc or ServerSendsDownloadFunc if the full generality of the BistreamFunc is not needed. For simplicity, the Server.RegisterServerSendsDownloadFunc() is used to register your ServerSendsDownloadFunc. Server.RegisterUploadReaderFunc() is used to register you UploadReaderFunc. Note in particular that the UploadReaderFunc is not persistent but rather receives a callback per Message received from the Client.Uploader. This may simplify the implementation of your server-side upload function. Note that persistent state between messages is still available by registering a method on your struct; see the ServerSideUploadFunc struct in example.go for example.

BistreamFunc, in contrast, are not a callback-per-message, but rather persist and would typically only exit if ctx.Done() is received, or if it wishes to finish the operation (say on an error, or by noting that a CallUploadEnd type Message has been received) so as to save goroutine resources on the server. The BistreamFunc is started on the server when the CallRequestBistreaming Message.HDR.Typ is received with the Subject matching the registered name. Each live instance of the BistreamFunc is identified by the req.HDR.CallID set by the originating client. All download messages sent will have this same CallID on them (for the client to match).

When the BistreamFunc finishes (returns), a final message will of type CallRPCReply will be sent back to the client. This is the lastReply *Message provided in the BistreamFunc. The BistreamFunc should fill in this lastReply with any final JobSerz payload it wishes to send; this is optional. On the client side, the Client.RequestBistreaming() is used to start bi-streaming. It returns a Bistreamer. This Bistreamer has a ReadCh that will receive this final message (as well as all other download messages). See the cli_test.go Test065_bidirectional_download_and_upload for example use.

A BistreamFunc is run on its own goroutine. It can start new goroutines, if it wishes, but this is not required. An additional (new) goroutine may be useful to reduce the latency of message handling while simultaneously reading from req.HDR.UploadsCh for uploads and writing to downloads with sendDownloadPartToClient(), as both of these are blocking, synchronous, operations. If you do so, be sure to handle goroutine cancellation and cleanup if the ctx provided is cancelled.

The sendDownloadPartToClient() helper function is used to write download Messages. It properly assigns the HDR.StreamPart sequence numbers and HDR.Typ as one of CallDownloadBegin, CallDownloadMore, and CallDownloadEnd). The BistreamFunc should call sendDownloadPartToClient() with last=true to signal the end of the download, in which case HDR.Typ CallDownloadEnd will be set on the sent Message.

To provide back-pressure by default, the sendDownloadPartToClient() call is synchronous and will return only when the message is sent. If you wish to continue to process uploads while sending a download part, your BistreamFunc can call the provided sendDownloadPartToClient() in a goroutine that you start for this purpose. The sendDownloadPartToClient() call is goroutine safe, as it uses its own internal sync.Mutex to ensure only one send is in progress at a time.

A BistreamFunc by default communicates download messages to its originating client. However other clients can also be sent messages. The Server.SendOneWayMessage() and Server.SendMessage() operations on the Server can be used for this purpose.

Visit the example.go implementation of ServeBistreamState.ServeBistream() to see it in action.

type Bistreamer

type Bistreamer struct {
	Seqno   uint64
	ReadCh  <-chan *Message
	WriteCh chan<- *Message
	Name    string
	// contains filtered or unexported fields
}

Bistreamer is the client side handle to talking with a server func that does bistreaming: the client can stream to the server func, and the server func can, symmetrically, stream to the client. The basics of TCP are finally available to users.

func (*Bistreamer) CallID

func (s *Bistreamer) CallID() string

func (*Bistreamer) UploadMore

func (s *Bistreamer) UploadMore(ctx context.Context, msg *Message, last bool) (err error)

type BuiltinTypes

type BuiltinTypes struct {
	Placeholder int `zid:"0"` // greenpack refuses to serialize an empty struct.
}

BuiltinTypes in example.go is part of the tests.

func (BuiltinTypes) Array

func (BuiltinTypes) Array(args *Args, reply *[2]int) error

BuiltinTypes.Array in example.go is part of the tests.

func (*BuiltinTypes) DecodeMsg

func (z *BuiltinTypes) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (BuiltinTypes) EncodeMsg

func (z BuiltinTypes) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (BuiltinTypes) Map

func (BuiltinTypes) Map(args *Args, reply *map[int]int) error

BuiltinTypes.Map in example.go is part of the tests.

func (BuiltinTypes) MarshalMsg

func (z BuiltinTypes) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (BuiltinTypes) Msgsize

func (z BuiltinTypes) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (BuiltinTypes) Slice

func (BuiltinTypes) Slice(args *Args, reply *[]int) error

BuiltinTypes.Slice in example.go is part of the tests.

func (*BuiltinTypes) UnmarshalMsg

func (z *BuiltinTypes) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*BuiltinTypes) UnmarshalMsgWithCfg

func (z *BuiltinTypes) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

func (BuiltinTypes) WantsContext

func (BuiltinTypes) WantsContext(ctx context.Context, args *Args, reply *[2]int) error

BuiltinTypes.WantsContext in example.go is part of the tests. Here, mimic Array's reply.

type Call

type Call struct {
	ServiceMethod string     // The name of the service and method to call.
	Args          Green      // The argument to the function (*struct).
	Reply         Green      // The reply from the function (*struct).
	Error         error      // After completion, the error status.
	Done          chan *Call // Receives *Call when Go is complete.
}

Call represents an active net/rpc RPC.

type CallType

type CallType int

const (
	CallNone CallType = 0

	CallRPC    CallType = 1
	CallNetRPC CallType = 2

	CallRequestBistreaming CallType = 3

	// All type numbers >= 10 are one-way calls.
	CallOneWay   CallType = 10
	CallRPCReply CallType = 11

	CallKeepAlive      CallType = 12
	CallCancelPrevious CallType = 13

	// client sends a stream to the server, in an Upload:
	CallUploadBegin CallType = 14 // one of these; and
	CallUploadMore  CallType = 15 // possibly many of these; and
	CallUploadEnd   CallType = 16 // just one of these to finish.

	// the opposite: when client wants to get a stream
	// from the server.
	CallRequestDownload CallType = 17

	// The server responds to CallRequestDownload with
	CallDownloadBegin CallType = 18 // one of these to start;
	CallDownloadMore  CallType = 19 // possibly many of these;
	CallDownloadEnd   CallType = 20 // and one of these to finish.
)

func (*CallType) DecodeMsg

func (z *CallType) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (CallType) EncodeMsg

func (z CallType) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (CallType) MarshalMsg

func (z CallType) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (CallType) Msgsize

func (z CallType) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (CallType) String

func (ct CallType) String() string

func (*CallType) UnmarshalMsg

func (z *CallType) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*CallType) UnmarshalMsgWithCfg

func (z *CallType) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type Client

type Client struct {
	// contains filtered or unexported fields
}

A Client starts requests, and (might) wait for responses.

func NewClient

func NewClient(name string, config *Config) (c *Client, err error)

NewClient creates a new client. Call Start() to begin a connection. The name setting allows users to track multiple instances of Clients, and the Client.Name() method will retreive it.

func (*Client) Call

func (c *Client) Call(serviceMethod string, args, reply Green, octx context.Context) error

Call implements the net/rpc Client.Call() API; its docs:

Call invokes the named function, waits for it to complete, and returns its error status.

Added: octx is an optional context for cancelling the job. It can be nil.

func (*Client) Close

func (c *Client) Close() error

Close shuts down the Client.

func (*Client) Err

func (c *Client) Err() error

Err returns any Client stored error.

func (*Client) GetOneRead

func (c *Client) GetOneRead(seqno uint64, ch chan *Message)

GetOneRead responds on ch with the first incoming message whose Seqno matches seqno, then auto unregisters itself after that single send on ch.

func (*Client) GetReadIncomingCh

func (c *Client) GetReadIncomingCh() (ch chan *Message)

GetReadIncomingCh creates and returns a buffered channel that reads incoming messages that are server-pushed (not associated with a round-trip rpc call request/response pair).

func (*Client) GetReadIncomingChForCallID

func (c *Client) GetReadIncomingChForCallID(callID string) (ch chan *Message)

GetReadIncomingChForCallID creates and returns a buffered channel that reads incoming messages that are server-pushed (not associated with a round-trip rpc call request/response pair). It filters for those with callID.

func (*Client) GetReads

func (c *Client) GetReads(ch chan *Message)

GetReads registers to get any received messages on ch. It is similar to GetReadIncomingCh but for when ch already exists and you do not want a new one.

func (*Client) GetReadsForCallID

func (c *Client) GetReadsForCallID(ch chan *Message, callID string)

GetReads registers to get any received messages on ch. It is similar to GetReadIncomingCh but for when ch already exists and you do not want a new one. It filters for CallID

func (*Client) Go

func (c *Client) Go(serviceMethod string, args Green, reply Green, done chan *Call, octx context.Context) *Call

Go implements the net/rpc Client.Go() API; its docs:

Go invokes the function asynchronously. It returns the Call structure representing the invocation. The done channel will signal when the call is complete by returning the same Call object. If done is nil, Go will allocate a new channel. If non-nil, done must be buffered or Go will deliberately crash.

octx is an optional context, for early cancelling of a job. It can be nil.

func (*Client) IsDown

func (c *Client) IsDown() (down bool)

func (*Client) LocalAddr

func (c *Client) LocalAddr() string

LocalAddr retreives the local host/port that the Client is calling from.

func (*Client) Name

func (c *Client) Name() string

Name reports the name the Client was created with.

func (*Client) OneWaySend

func (c *Client) OneWaySend(msg *Message, cancelJobCh <-chan struct{}) (err error)

OneWaySend sends a message without expecting or waiting for a response. The cancelJobCh is optional, and can be nil. If msg.HDR.CallID is set, we will preserve it.

func (*Client) RequestBistreaming

func (c *Client) RequestBistreaming(ctx context.Context, bistreamerName string, req *Message) (b *Bistreamer, err error)

func (*Client) RequestDownload

func (c *Client) RequestDownload(ctx context.Context, streamerName string) (downloader *Downloader, err error)

func (*Client) SendAndGetReply

func (c *Client) SendAndGetReply(req *Message, cancelJobCh <-chan struct{}) (reply *Message, err error)

SendAndGetReply starts a round-trip RPC call. We will wait for a response before retuning. The requestStopCh is optional; it can be nil. A context.Done() like channel can be supplied there to cancel the job before a reply comes back.

UPDATE: a DEFAULT timeout is in force now. Because server failure or blink (down then up) can leave us stalled forever, we put in a default timeout of 10 seconds, if not otherwise specified. If you expect your call to take more than a few seconds, you should set the timeout directly with SendAndGetReplyWithTimeout() or pass in a cancelJobCh here to manage it. Otherwise, to handle the common case when we expect very fast replies, if cancelJobCh is nil, we will cancel the job if it has not finished after 10 seconds.

func (*Client) SendAndGetReplyWithCtx

func (c *Client) SendAndGetReplyWithCtx(ctx context.Context, req *Message) (reply *Message, err error)

SendAndGetReplyWithCtx is like SendAndGetReply(), with the additional feature that it will send a remote cancellation request when the ctx is cancelled or if the ctx.Deadline() time (if set) is surpassed. Note that none of the Values inside ctx, if set, will be transmitted to the remote call, because the context.Context API provides no method to enumerate them. Such values are likely not serializable in any case.

A similar deadline effect can be acheived just by setting the req.HDR.Deadline field in a SendAndGetReply() call. This may also be more efficient on the client, because the client need not wait for the remote cancellation response to be sent and received. However this is a little racey: the server could suceed and be in the process of replying when the client hits the deadline. In this case the client might retry a call that actually did finish, and end up doing the call twice. This is also always a hazard with servers crashing before they can finish responding. Ideally server APIs are idempotent to guard against this.

func (*Client) SendAndGetReplyWithTimeout

func (c *Client) SendAndGetReplyWithTimeout(timeout time.Duration, req *Message) (reply *Message, err error)

SendAndGetReplyWithTimeout expires the call after timeout.

func (*Client) Start

func (c *Client) Start() error

Start dials the server. That is, Start attemps to connect to config.ClientDialToHostPort. The err will come back with any problems encountered.

func (*Client) UngetReads

func (c *Client) UngetReads(ch chan *Message)

UngetReads reverses what GetReads does: un-register and have ch be deaf from now on. Idempotent: if ch is already gone, no foul is reported.

func (*Client) UploadBegin

func (c *Client) UploadBegin(
	ctx context.Context,
	msg *Message,

) (strm *Uploader, err error)

UploadBegin sends the msg to the server to execute with the func that has registed with RegisterUploaderReadererFunc() -- at the moment there can only be one such func registered at a time. UploadBegin() will contact it, and Uploader.UploadMore() will, as it suggests, send another Message.

We maintain FIFO arrival of Messages at the server as follows (despite having each server side func callback executing in a goroutine).

1. Since the client side uses the same channel into the send loop for both UploadBegin and UploadMore, these calls will be properly ordered into the send loop on the client/sending side.

2. The TCP/QUIC stream maintains FIFO order of its messages as it delivers them to the server.

3. On the server, in the TCP/QUIC read loop, we queue messages in FIFO order into a large buffered channel before we spin up a goroutine once at UploadBegin time to handle all the subsequent messages in the order they were queued.

This also yeilds an efficient design. While normal OneWayFunc and TwoWayFunc messages each start their own new goroutine to avoid long-running functions starving the server's read loop, a UploadReadFunc only utilizes a single new goroutine to process all messages sent in a stream.

type ClientCodec

type ClientCodec interface {
	WriteRequest(*Request, msgp.Encodable) error
	ReadResponseHeader(*Response) error
	ReadResponseBody(msgp.Decodable) error

	Close() error
}

ClientCodec is part of the net/rpc API. Its docs:

A ClientCodec implements writing of RPC requests and reading of RPC responses for the client side of an RPC session. The client calls [ClientCodec.WriteRequest] to write a request to the connection and calls [ClientCodec.ReadResponseHeader] and [ClientCodec.ReadResponseBody] in pairs to read responses. The client calls [ClientCodec.Close] when finished with the connection. ReadResponseBody may be called with a nil argument to force the body of the response to be read and then discarded. See NewClient's comment for information about concurrent access.

type Config

type Config struct {

	// ServerAddr host:port where the server should listen.
	ServerAddr string

	// optional. Can be used to suggest that the
	// client use a specific host:port. NB: For QUIC, by default, the client and
	// server will share the same port if they are in the same process.
	// In that case this setting will definitely be ignored.
	ClientHostPort string

	// Who the client should contact
	ClientDialToHostPort string

	// TCP false means TLS-1.3 secured. true here means do TCP only; with no encryption.
	TCPonly_no_TLS bool

	// UseQUIC cannot be true if TCPonly_no_TLS is true.
	UseQUIC bool

	// NoSharePortQUIC defaults false so sharing is allowed.
	// If true, then we do not share same UDP port between a QUIC
	// client and server (in the same process). Used
	// for testing client shutdown paths too.
	NoSharePortQUIC bool

	// path to certs/ like certificate
	// directory on the live filesystem.
	CertPath string

	// SkipVerifyKeys true allows any incoming
	// key to be signed by
	// any CA; it does not have to be ours. Obviously
	// this discards almost all access control; it
	// should rarely be used unless communication
	// with the any random agent/hacker/public person
	// is desired.
	SkipVerifyKeys bool

	ClientKeyPairName string // default "client" means use certs/client.crt and certs/client.key
	ServerKeyPairName string // default "node" means use certs/node.crt and certs/node.key

	// PreSharedKeyPath locates an optional pre-shared
	// key. It must be 32 bytes (or more). Ideally
	// it should be generated from crypto/rand.
	// The `selfy -gensym outpath` command will
	// write 32 randomly bytes to output.
	PreSharedKeyPath string

	// These are timeouts for connection and transport tuning.
	// The defaults of 0 mean wait forever.
	//
	// Generally we want our send loops to wait forever because
	// if the cut off a send mid-message, it is hard to recover;
	// we don't pass back up the stack how much of the broken
	// message was sent, so the only thing we can do then is tear
	// down the connection pair and re-connect. It is much
	// better to just dedicate the sendLoops to writing for as
	// long as it takes than to set a WriteTimeout.
	ConnectTimeout time.Duration
	ReadTimeout    time.Duration
	WriteTimeout   time.Duration

	ServerSendKeepAlive time.Duration
	ClientSendKeepAlive time.Duration

	// Intially speak HTTP and only
	// accept CONNECT requests that
	// we turn into our protocol.
	// Only works with TCPonly_no_TLS true also,
	// at the moment. Also adds on another
	// round trip.
	HTTPConnectRequired bool
	// contains filtered or unexported fields
}

Config is the same struct type for both NewClient and NewServer setup.

Config says who to contact (for a client), or where to listen (for a server and/or client); and sets how strong a security posture we adopt.

Copying a Config is fine, but it should be a simple shallow copy to preserve the shared *sharedTransport struct. See/use the Config.Clone() method if in doubt.

nitty gritty details/dev note: the `shared` pointer here is the basis of port (and file handle) reuse where a single process can maintain a server and multiple clients in a "star" pattern. This only works with QUIC of course, and is one of the main reasons to use QUIC.

The shared pointer is reference counted and the underlying net.UDPConn is only closed when the last instance in use is Close()-ed.

func NewConfig

func NewConfig() *Config

NewConfig should be used to create Config for use in NewClient or NewServer setup.

func (*Config) Clone

func (cfg *Config) Clone() *Config

Clone returns a copy of cfg. This is a shallow copy to enable shared transport between a QUIC client and a QUIC server on the same port.

type Downloader

type Downloader struct {
	CallID string
	Seqno  uint64
	ReadCh <-chan *Message
	Name   string
}

Downloader is used when the client receives stream from server. It is returned by RequestDownload().

type Embed

type Embed struct {
	Simple `zid:"0"`
}

Embed in example.go is part of the tests.

func (*Embed) DecodeMsg

func (z *Embed) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (Embed) EncodeMsg

func (z Embed) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (Embed) MarshalMsg

func (z Embed) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (Embed) Msgsize

func (z Embed) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*Embed) UnmarshalMsg

func (z *Embed) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*Embed) UnmarshalMsgWithCfg

func (z *Embed) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type Green

type Green interface {
	msgp.Encodable
	msgp.Decodable
}

type HDR

type HDR struct {

	// Nc is supplied to reveal the LocalAddr() or RemoteAddr() end points.
	// Do not read from, or write to, this connection;
	// that will cause the RPC connection to fail.
	Nc net.Conn `msg:"-"`

	Created time.Time `zid:"0"` // HDR creation time stamp.
	From    string    `zid:"1"` // originator host:port address.
	To      string    `zid:"2"` // destination host:port address.
	Subject string    `zid:"3"` // in net/rpc, the "Service.Method" ServiceName
	Seqno   uint64    `zid:"4"` // user (client) set sequence number for each call (same on response).
	Typ     CallType  `zid:"5"` // see constants below.
	CallID  string    `zid:"6"` // 20 bytes pseudo random base-64 coded string (same on response).
	Serial  int64     `zid:"7"` // system serial number

	LocalRecvTm time.Time `zid:"8"`

	// allow standard []byte oriented message to cancel too.
	Ctx context.Context `msg:"-"`

	// Deadline is optional, but if it is set on the client,
	// the server side context.Context will honor it.
	Deadline time.Time `zid:"9"` // if non-zero, set this deadline in the remote Ctx

	// The CallID will be identical on
	// all parts of the same stream.
	StreamPart int64 `zid:"10"`
	// contains filtered or unexported fields
}

HDR provides header information and details about the transport. It is the first thing in every Message. It is public so that clients can understand the context of their calls. Traditional `net/rpc` API users can use the `ctx context.Context` first argument form of callback methods and get an *HDR with HDRFromContext() as in the README.md introduction. Reproduced here:

func (s *Service) GetsContext(ctx context.Context, args *Args, reply *Reply) error {
    if hdr, ok := HDRFromContext(ctx); ok {
       fmt.Printf("GetsContext called with HDR = '%v'; "+
          "HDR.Nc.RemoteAddr() gives '%v'; HDR.Nc.LocalAddr() gives '%v'\n",
          hdr.String(), hdr.Nc.RemoteAddr(), hdr.Nc.LocalAddr())
    }
}

func HDRFromBytes

func HDRFromBytes(jsonData []byte) (*HDR, error)

func HDRFromContext

func HDRFromContext(ctx context.Context) (*HDR, bool)

HDRFromContext returns the User value stored in ctx, if any.

func HDRFromGreenpack

func HDRFromGreenpack(header []byte) (*HDR, error)

HDRFromGreenpack will unmarshal the header into the returned struct. The [greenpack format](https://github.com/glycerine/greenpack) is expected.

func NewHDR

func NewHDR(from, to, subject string, typ CallType, streamPart int64) (m *HDR)

NewHDR creates a new HDR header.

func Unbytes

func Unbytes(jsonData []byte) *HDR

Unbytes reverses Bytes.

func (*HDR) AsGreenpack

func (hdr *HDR) AsGreenpack(scratch []byte) (o []byte, err error)

AsGreenpack will marshall hdr into the o output bytes. The scratch bytes can be nil or reused and returned to avoid allocation. The [greenpack format](https://github.com/glycerine/greenpack) is used.

func (*HDR) Bytes

func (m *HDR) Bytes() []byte

Bytes serializes to compact JSON formatted bytes.

func (*HDR) Compact

func (m *HDR) Compact() string

Compact is all on one line.

func (*HDR) DecodeMsg

func (z *HDR) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (*HDR) EncodeMsg

func (z *HDR) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (*HDR) Equal

func (a *HDR) Equal(b *HDR) bool

Equal compares two *HDR structs field by field for structural equality

func (*HDR) JSON

func (m *HDR) JSON() []byte

JSON serializes to JSON.

func (*HDR) MarshalMsg

func (z *HDR) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (*HDR) Msgsize

func (z *HDR) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*HDR) Pretty

func (m *HDR) Pretty() string

Pretty shows in pretty-printed JSON format.

func (*HDR) String

func (m *HDR) String() string

func (*HDR) UnmarshalMsg

func (z *HDR) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*HDR) UnmarshalMsgWithCfg

func (z *HDR) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type Hello

type Hello struct {
	Placeholder int `zid:"0"` // must have public field or greenpack will ignore it.
}

Hello in example.go is part of the tests.

func (*Hello) DecodeMsg

func (z *Hello) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (Hello) EncodeMsg

func (z Hello) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (Hello) MarshalMsg

func (z Hello) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (Hello) Msgsize

func (z Hello) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*Hello) UnmarshalMsg

func (z *Hello) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*Hello) UnmarshalMsgWithCfg

func (z *Hello) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type InvalidRequest

type InvalidRequest struct {
	Placeholder int `zid:"0"`
}

InvalidRequest used instead of struct{} since greenpack needs one member element.

func (*InvalidRequest) DecodeMsg

func (z *InvalidRequest) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (InvalidRequest) EncodeMsg

func (z InvalidRequest) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (InvalidRequest) MarshalMsg

func (z InvalidRequest) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (InvalidRequest) Msgsize

func (z InvalidRequest) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*InvalidRequest) UnmarshalMsg

func (z *InvalidRequest) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*InvalidRequest) UnmarshalMsgWithCfg

func (z *InvalidRequest) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type Message

type Message struct {

	// HDR contains header information.
	HDR HDR `zid:"0"`

	// JobSerz is the "body" of the message.
	// The user provides and interprets this.
	JobSerz []byte `zid:"1"`

	// JobErrs returns error information from the server-registered
	// user-defined callback functions.
	JobErrs string `zid:"2"`

	// LocalErr is not serialized on the wire by the server.
	// It communicates only local (client/server side) information.
	//
	// Callback functions convey
	// errors in JobErrs (by returning an error);
	// or in-band within JobSerz.
	LocalErr error `msg:"-"`

	// DoneCh will receive this Message itself when the call completes.
	// It must be buffered, with at least capacity 1.
	// NewMessage() automatically allocates DoneCh correctly and
	// should be used when creating a new Message.
	DoneCh chan *Message `msg:"-"`
	// contains filtered or unexported fields
}

Message transports JobSerz []byte slices for the user, who can de-serialize them they wish. The HDR header field provides transport details.

func MessageFromGreenpack

func MessageFromGreenpack(by []byte) (*Message, error)

MessageFromGreenpack unmarshals the by slice into a Message and returns it. The [greenpack format](https://github.com/glycerine/greenpack) is expected.

func NewMessage

func NewMessage() *Message

NewMessage allocates a new Message with a DoneCh properly created (buffered 1).

func NewMessageFromBytes

func NewMessageFromBytes(by []byte) (msg *Message)

NewMessageFromBytes calls NewMessage() and sets by as the JobSerz field.

func (*Message) AsGreenpack

func (m *Message) AsGreenpack(scratch []byte) (o []byte, err error)

AsGreenpack marshalls m into o. The scratch workspace can be nil or reused to avoid allocation. The [greenpack format](https://github.com/glycerine/greenpack) is used. The m.JobSerz payload must be <= maxMessage-1024, or we will return ErrTooLarge without trying to serialize it.

func (*Message) AsJSON

func (m *Message) AsJSON(scratch []byte) (o []byte, err error)

AsJSON returns JSON bytes via msgp.CopyToJSON() or msgp.UnmarshalAsJSON()

func (*Message) DecodeMsg

func (z *Message) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (*Message) EncodeMsg

func (z *Message) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (*Message) MarshalMsg

func (z *Message) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (*Message) Msgsize

func (z *Message) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*Message) String

func (msg *Message) String() string

String returns a string representation of msg.

func (*Message) UnmarshalMsg

func (z *Message) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*Message) UnmarshalMsgWithCfg

func (z *Message) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type MustBeCancelled

type MustBeCancelled struct {
	// as greenpack efficiently does nothing without any member elements.
	Placeholder int `zid:"0"`
}

The MustBeCancelled struct in example.go is part of the tests. See cli_test.go Test040 for details.

func NewMustBeCancelled

func NewMustBeCancelled() *MustBeCancelled

NewMustBeCancelled in example.go is part of the tests. See cli_test.go Test040 for details.

func (*MustBeCancelled) DecodeMsg

func (z *MustBeCancelled) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (MustBeCancelled) EncodeMsg

func (z MustBeCancelled) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (MustBeCancelled) MarshalMsg

func (z MustBeCancelled) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (*MustBeCancelled) MessageAPI_HangUntilCancel

func (s *MustBeCancelled) MessageAPI_HangUntilCancel(req, reply *Message) error

MessageAPI_HangUntilCancel in example.go is part of the tests. See cli_test.go Test040 for details.

func (MustBeCancelled) Msgsize

func (z MustBeCancelled) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*MustBeCancelled) UnmarshalMsg

func (z *MustBeCancelled) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*MustBeCancelled) UnmarshalMsgWithCfg

func (z *MustBeCancelled) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

func (*MustBeCancelled) WillHangUntilCancel

func (s *MustBeCancelled) WillHangUntilCancel(ctx context.Context, args *Args, reply *Reply) error

WillHangUntilCancel in example.go is part of the tests. See cli_test.go Test040 for details.

type NetConnWrapper

type NetConnWrapper struct {
	quic.Stream
	quic.Connection
}

NetConnWrapper is exported so that clients like `goq` and others that want to inspect that context of their calls can do so.

func (*NetConnWrapper) Close

func (w *NetConnWrapper) Close() error

type OneWayFunc

type OneWayFunc func(req *Message)

OneWayFunc is the simpler sibling to the above. A OneWayFunc will not return anything to the sender.

As above req.JobSerz [] byte contains the job payload.

type Reply

type Reply struct {
	C int `zid:"0"`
}

Reply in example.go is part of the tests.

func (*Reply) DecodeMsg

func (z *Reply) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (Reply) EncodeMsg

func (z Reply) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (Reply) MarshalMsg

func (z Reply) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (Reply) Msgsize

func (z Reply) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*Reply) UnmarshalMsg

func (z *Reply) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*Reply) UnmarshalMsgWithCfg

func (z *Reply) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type Request

type Request struct {
	ServiceMethod string `zid:"0"` // format: "Service.Method"
	Seq           uint64 `zid:"1"` // sequence number chosen by client
	// contains filtered or unexported fields
}

Request is part of the net/rpc API. Its docs:

Request is a header written before every RPC call. It is used internally but documented here as an aid to debugging, such as when analyzing network traffic.

func (*Request) DecodeMsg

func (z *Request) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (Request) EncodeMsg

func (z Request) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (Request) MarshalMsg

func (z Request) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (Request) Msgsize

func (z Request) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*Request) UnmarshalMsg

func (z *Request) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*Request) UnmarshalMsgWithCfg

func (z *Request) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type Response

type Response struct {
	ServiceMethod string `zid:"0"` // echoes that of the Request
	Seq           uint64 `zid:"1"` // echoes that of the request
	Error         string `zid:"2"` // error, if any.
	// contains filtered or unexported fields
}

Response is part of the net/rpc API. Its docs:

Response is a header written before every RPC return. It is used internally but documented here as an aid to debugging, such as when analyzing network traffic.

func (*Response) DecodeMsg

func (z *Response) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (Response) EncodeMsg

func (z Response) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (Response) MarshalMsg

func (z Response) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (Response) Msgsize

func (z Response) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*Response) UnmarshalMsg

func (z *Response) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*Response) UnmarshalMsgWithCfg

func (z *Response) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type ServeBistreamState

type ServeBistreamState struct{}

ServeBistreamState is used by Test065_bidirectional_streaming test.

func (*ServeBistreamState) ServeBistream

func (bi *ServeBistreamState) ServeBistream(
	srv *Server,
	ctx context.Context,
	req *Message,
	uploadsFromClientCh <-chan *Message,
	sendDownloadPartToClient func(ctx context.Context, by []byte, last bool),
	lastReply *Message,
) (err error)

ServeBistream is an example of a BistreamFunc, a server side registered function for bi-streaming (doing both upload and download simultaneously). See cli_test.go Test065_bidirectional_download_and_upload for a test that uses this method.

type Server

type Server struct {

	// RemoteConnectedCh sends the remote host:port address
	// when the server gets a new client,
	// See srv_test.go Test004_server_push for example,
	// where it is used to avoid a race/panic.
	RemoteConnectedCh chan *ServerClient
	// contains filtered or unexported fields
}

Servers read and respond to requests. Two APIs are available.

Using the rpc25519.Message based API:

Register1Func() and Register2Func() register callbacks.

Using the net/rpc API:

Server.Register() registers structs with callback methods on them.

The net/rpc API is implemented as a layer on top of the rpc25519.Message based API. Both can be used concurrently if desired.

func NewServer

func NewServer(name string, config *Config) *Server

NewServer will keep its own copy of config. If config is nil, the server will make its own upon Start().

func (*Server) Close

func (s *Server) Close() error

Close asks the Server to shut down.

func (*Server) Register

func (s *Server) Register(rcvr msgp.Encodable) error

Register implements the net/rpc Server.Register() API. Its docs:

Register publishes in the server the set of methods of the receiver value that satisfy the following conditions:

• exported method of exported type
• two arguments, both of exported type
• the second argument is a pointer
• one return value, of type error

It returns an error if the receiver is not an exported type or has no suitable methods. It also logs the error using package log. The client accesses each method using a string of the form "Type.Method", where Type is the receiver's concrete type.

rpc25519 addendum:

Callback methods in the `net/rpc` style traditionally look like this first `NoContext` example below. We now allow a context.Context as an additional first parameter. The ctx will a pointer to the `rpc25519.HDR` header from the incoming Message set on it. Call rpc25519.HDRFromContext() to retreive it.

func (s *Service) NoContext(args *Args, reply *Reply) error

* new:

func (s *Service) GetsContext(ctx context.Context, args *Args, reply *Reply) error {
  if hdr, ok := rpc25519.HDRFromContext(ctx); ok {
        fmt.Printf("GetsContext called with HDR = '%v'; "+
             "HDR.Nc.RemoteAddr() gives '%v'; HDR.Nc.LocalAddr() gives '%v'\n",
             h.String(), h.Nc.RemoteAddr(), h.Nc.LocalAddr())
   } else {
        fmt.Println("HDR not found")
   }
}

func (*Server) Register1Func

func (s *Server) Register1Func(callme1 OneWayFunc)

Register1Func tells the server about a func or method that will not reply. See the OneWayFunc definition.

func (*Server) Register2Func

func (s *Server) Register2Func(callme2 TwoWayFunc)

Register2Func tells the server about a func or method that will have a returned Message value. See the TwoWayFunc definition.

func (*Server) RegisterBistreamFunc

func (s *Server) RegisterBistreamFunc(name string, callme BistreamFunc)

func (*Server) RegisterName

func (s *Server) RegisterName(name string, rcvr msgp.Encodable) error

RegisterName is like [Register] but uses the provided name for the type instead of the receiver's concrete type.

func (*Server) RegisterServerSendsDownloadFunc

func (s *Server) RegisterServerSendsDownloadFunc(name string, callme ServerSendsDownloadFunc)

func (*Server) RegisterUploadReaderFunc

func (s *Server) RegisterUploadReaderFunc(callmeUploadReader UploadReaderFunc)

RegisterUploadReaderFunc tells the server about a func or method to handle uploads. See the UploadReaderFunc definition.

func (*Server) SendMessage

func (s *Server) SendMessage(callID, subject, destAddr string, data []byte, seqno uint64,
	errWriteDur *time.Duration) error

SendMessage can be used on the server to push data to one of the connected clients.

The Message msg should have msg.JobSerz set, as well as the HDR fields Subject, CallID, and Seqno. The NewCallID() can be used to generate a random (without conflicts with prior CallID if needed/not matching a previous call.

If the HDR.To destination address is not already connected to the server, the ErrNetConnectionNotFound error will be returned.

errWriteDur is how long we pause waiting for the writing goroutine to send the message or give us a fast error reply. Early discovery of client disconnect can allow us to try other (worker) clients, rather than wait for pings or other slow error paths.

The errWriteDur can be set to a few seconds if this would save the caller a minute of two of waiting to discover the send is unlikely to suceed; or to time.Duration(0) if they want no pause after writing Message to the connection. The default is 30 msec. It is a guess and aims at balance: allowing enough time to get an error back from quic-go if we are going to discover "Application error 0x0 (remote)" right away, and not wanting to stall the caller too much.

func (*Server) SendOneWayMessage

func (s *Server) SendOneWayMessage(ctx context.Context, msg *Message, errWriteDur *time.Duration) error

SendOneWayMessage is the same as SendMessage above except that it takes a fully prepared msg to avoid API churn when new HDR fields are added/needed. msg.HDR.Type must be >= CallOneWay (10), to try and catch mis-use of this when the user actually wants a round-trip call.

func (*Server) ServeHTTP

func (server *Server) ServeHTTP(w http.ResponseWriter, req *http.Request)

ServeHTTP implements an http.Handler that answers RPC requests.

func (*Server) Start

func (s *Server) Start() (serverAddr net.Addr, err error)

Start has the Server begin receiving and processing RPC calls. The Config.ServerAddr tells us what host:port to bind and listen on.

type ServerClient

type ServerClient struct {
	Remote string
	GoneCh chan struct{}
}

type ServerCodec

type ServerCodec interface {
	ReadRequestHeader(*Request) error
	ReadRequestBody(msgp.Decodable) error
	WriteResponse(*Response, msgp.Encodable) error

	// Close can be called multiple times and must be idempotent.
	Close() error
}

ServerCodec is part of the net/rpc API. Its docs:

A ServerCodec implements reading of RPC requests and writing of RPC responses for the server side of an RPC session. The server calls [ServerCodec.ReadRequestHeader] and [ServerCodec.ReadRequestBody] in pairs to read requests from the connection, and it calls [ServerCodec.WriteResponse] to write a response back. The server calls [ServerCodec.Close] when finished with the connection. ReadRequestBody may be called with a nil argument to force the body of the request to be read and discarded. See NewClient's comment for information about concurrent access.

type ServerError

type ServerError string

ServerError represents an error that has been returned from the remote side of the RPC connection.

func (ServerError) Error

func (e ServerError) Error() string

type ServerSendsDownloadFunc

type ServerSendsDownloadFunc func(
	srv *Server,
	ctx context.Context,
	req *Message,
	sendDownloadPartToClient func(ctx context.Context, by []byte, last bool),
	lastReply *Message,
) (err error)

ServerSendsDownloadFunc is used to send a stream to the client on the streamToClientChan. Use Server.RegisterServerSendsDownloadFunc() to register it.

type ServerSendsDownloadState

type ServerSendsDownloadState struct{}

func (*ServerSendsDownloadState) ServerSendsDownload

func (ssss *ServerSendsDownloadState) ServerSendsDownload(srv *Server, ctx context.Context, req *Message, sendStreamPart func(ctx context.Context, by []byte, last bool), lastReply *Message) (err error)

ServerSendsDownload is used by Test055_streaming_server_to_client. It demonstrates how a registered server func can stream to the client. ServerSendStream has type ServerSendsDownloadFunc, and gets registered on the server with srv.RegisterServerSendsDownloadFunc().

type ServerSideUploadState

type ServerSideUploadState struct {
	// contains filtered or unexported fields
}

ServerSideUploadState is used by Test045_streaming_client_to_server (upload) in cli_test.go and cmd/srv/server.go to demonstrate streaming a large (or infinite) file in small parts, from client to server, all while keeping FIFO message order.

func NewServerSideUploadState

func NewServerSideUploadState() *ServerSideUploadState

NewServerSideUploadState returns a new ServerSideUploadState. This is part of the cli_test.go Test045 mechanics.

func (*ServerSideUploadState) ReceiveFileInParts

func (s *ServerSideUploadState) ReceiveFileInParts(req *Message, lastReply *Message) (err error)

ReceiveFileInParts is used by Test045_streaming_client_to_server in cli_test.go to demonstrate streaming from client to server.

See the cmd/cli/client.go and cmd/srv/server.go and their (cli -sendfile) and (srv -readfile) flags for a full implementation of an scp-like utility that uses this method.

ReceiveFileInParts is an UploadReaderFunc and is registered on the Server with the Server.RegisterUploadReaderFunc() call.

type Simple

type Simple int

Simple in example.go is part of the tests.

func (*Simple) DecodeMsg

func (z *Simple) DecodeMsg(dc *msgp.Reader) (err error)

DecodeMsg implements msgp.Decodable We treat empty fields as if we read a Nil from the wire.

func (Simple) EncodeMsg

func (z Simple) EncodeMsg(en *msgp.Writer) (err error)

EncodeMsg implements msgp.Encodable

func (*Simple) Exported

func (t *Simple) Exported(args Args, reply *Reply) error

Simple.Exported in example.go is part of the tests.

func (Simple) MarshalMsg

func (z Simple) MarshalMsg(b []byte) (o []byte, err error)

MarshalMsg implements msgp.Marshaler

func (Simple) Msgsize

func (z Simple) Msgsize() (s int)

Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message

func (*Simple) UnmarshalMsg

func (z *Simple) UnmarshalMsg(bts []byte) (o []byte, err error)

UnmarshalMsg implements msgp.Unmarshaler

func (*Simple) UnmarshalMsgWithCfg

func (z *Simple) UnmarshalMsgWithCfg(bts []byte, cfg *msgp.RuntimeConfig) (o []byte, err error)

type TwoWayFunc

type TwoWayFunc func(req *Message, reply *Message) error

TwoWayFunc is the user's own function that they register with the server for remote procedure calls.

The user's Func may not want to return anything. In that case they should register a OneWayFunc instead.

req.JobSerz []byte contains the job payload.

Implementers of TwoWayFunc should assign their return []byte to reply.JobSerz. reply.Jobserz can also be left nil, of course.

Any errors can be returned on reply.JobErrs; this is optional. Note that JobErrs is a string value rather than an error.

The system will overwrite the reply.HDR field when sending the reply, so the user should not bother trying to alter it. The one exception to this rule is the reply.HDR.Subject string, which can be set by the user to return user-defined information. The reply will still be matched to the request on the HDR.Seqno, so a change of HDR.Subject will not change which goroutine receives the reply.

type UploadReaderFunc

type UploadReaderFunc func(req *Message, lastReply *Message) error

A UploadReaderFunc receives messages from a Client's upload. It corresponds to the client-side Uploader, created by Client.UploadBegin().

For a quick example, see the ReceiveFileInParts() implementation in the example.go file. It is a method on the ServerSideUploadFunc struct that holds state between the callbacks to ReceiveFileInParts().

A UploadReaderFunc is like a OneWayFunc, but it generally should also be a method or closure to capture the state it needs, as it will receive multiple req *Message up-calls from the same client Stream. It should return a non-nil error to tell the client to stop sending. A nil return means we are fine and want to continue to receive more Messages from the same Stream. The req.HDR.CallID can be used to identify distinct Streams, and the req.HDR.StreamPart will convey their order which will start at 0 and count up.

The lastReply argument will be nil until the Client calls Stream.More() with the last argument set to true. The user/client is telling the UploadReaderFunc not to expect any further messages. The UploadReaderFunc can then fill in the lastReply message with any finishing detail, and it will be sent back to the client.

Note that even when lastReply is not nil, req may still have the tail content of the stream, and so generally req should be processed before considering if this is the last message and a final lastReply should also be filled out.

type Uploader

type Uploader struct {
	ReadCh <-chan *Message
	// contains filtered or unexported fields
}

Uploader helps the client to make a series of non-blocking (one-way) calls to a remote server's UploadReaderFunc which must have been already registered on the server.

func (*Uploader) CallID

func (s *Uploader) CallID() string

func (*Uploader) UploadMore

func (s *Uploader) UploadMore(ctx context.Context, msg *Message, last bool) (err error)