Documentation ¶
Overview ¶
Package mqtt provides an MQTT v3.1.1 client library.
Index ¶
- Constants
- Variables
- func DefaultConnectionLostHandler(client Client, reason error)
- type Client
- type ClientOptions
- func (o *ClientOptions) AddBroker(server string) *ClientOptions
- func (o *ClientOptions) SetAutoReconnect(a bool) *ClientOptions
- func (o *ClientOptions) SetBinaryWill(topic string, payload []byte, qos byte, retained bool) *ClientOptions
- func (o *ClientOptions) SetCleanSession(clean bool) *ClientOptions
- func (o *ClientOptions) SetClientID(id string) *ClientOptions
- func (o *ClientOptions) SetConnectTimeout(t time.Duration) *ClientOptions
- func (o *ClientOptions) SetConnectionLostHandler(onLost ConnectionLostHandler) *ClientOptions
- func (o *ClientOptions) SetCredentialsProvider(p CredentialsProvider) *ClientOptions
- func (o *ClientOptions) SetDefaultPublishHandler(defaultHandler MessageHandler) *ClientOptions
- func (o *ClientOptions) SetHTTPHeaders(h http.Header) *ClientOptions
- func (o *ClientOptions) SetKeepAlive(k time.Duration) *ClientOptions
- func (o *ClientOptions) SetMaxReconnectInterval(t time.Duration) *ClientOptions
- func (o *ClientOptions) SetMessageChannelDepth(s uint) *ClientOptions
- func (o *ClientOptions) SetOnConnectHandler(onConn OnConnectHandler) *ClientOptions
- func (o *ClientOptions) SetOrderMatters(order bool) *ClientOptions
- func (o *ClientOptions) SetPassword(p string) *ClientOptions
- func (o *ClientOptions) SetPingTimeout(k time.Duration) *ClientOptions
- func (o *ClientOptions) SetProtocolVersion(pv uint) *ClientOptions
- func (o *ClientOptions) SetResumeSubs(resume bool) *ClientOptions
- func (o *ClientOptions) SetStore(s Store) *ClientOptions
- func (o *ClientOptions) SetTLSConfig(t *tls.Config) *ClientOptions
- func (o *ClientOptions) SetUsername(u string) *ClientOptions
- func (o *ClientOptions) SetWill(topic string, payload string, qos byte, retained bool) *ClientOptions
- func (o *ClientOptions) SetWriteTimeout(t time.Duration) *ClientOptions
- func (o *ClientOptions) UnsetWill() *ClientOptions
- type ClientOptionsReader
- func (r *ClientOptionsReader) AutoReconnect() bool
- func (r *ClientOptionsReader) CleanSession() bool
- func (r *ClientOptionsReader) ClientID() string
- func (r *ClientOptionsReader) ConnectTimeout() time.Duration
- func (r *ClientOptionsReader) HTTPHeaders() http.Header
- func (r *ClientOptionsReader) KeepAlive() time.Duration
- func (r *ClientOptionsReader) MaxReconnectInterval() time.Duration
- func (r *ClientOptionsReader) MessageChannelDepth() uint
- func (r *ClientOptionsReader) Order() bool
- func (r *ClientOptionsReader) Password() string
- func (r *ClientOptionsReader) PingTimeout() time.Duration
- func (r *ClientOptionsReader) ProtocolVersion() uint
- func (r *ClientOptionsReader) ResumeSubs() bool
- func (r *ClientOptionsReader) Servers() []*url.URL
- func (r *ClientOptionsReader) TLSConfig() *tls.Config
- func (r *ClientOptionsReader) Username() string
- func (r *ClientOptionsReader) WillEnabled() bool
- func (r *ClientOptionsReader) WillPayload() []byte
- func (r *ClientOptionsReader) WillQos() byte
- func (r *ClientOptionsReader) WillRetained() bool
- func (r *ClientOptionsReader) WillTopic() string
- func (r *ClientOptionsReader) WriteTimeout() time.Duration
- type ConnectToken
- type ConnectionLostHandler
- type CredentialsProvider
- type DisconnectToken
- type DummyToken
- type FileStore
- func (store *FileStore) All() []string
- func (store *FileStore) Close()
- func (store *FileStore) Del(key string)
- func (store *FileStore) Get(key string) packets.ControlPacket
- func (store *FileStore) Open()
- func (store *FileStore) Put(key string, m packets.ControlPacket)
- func (store *FileStore) Reset()
- type Logger
- type MId
- type MemoryStore
- func (store *MemoryStore) All() []string
- func (store *MemoryStore) Close()
- func (store *MemoryStore) Del(key string)
- func (store *MemoryStore) Get(key string) packets.ControlPacket
- func (store *MemoryStore) Open()
- func (store *MemoryStore) Put(key string, message packets.ControlPacket)
- func (store *MemoryStore) Reset()
- type Message
- type MessageHandler
- type NOOPLogger
- type OnConnectHandler
- type PacketAndToken
- type PublishToken
- type Store
- type SubscribeToken
- type Token
- type TokenErrorSetter
- type UnsubscribeToken
Constants ¶
const ( NET component = "[net] " PNG component = "[pinger] " CLI component = "[client] " DEC component = "[decode] " MES component = "[message] " STR component = "[store] " MID component = "[msgids] " TST component = "[test] " STA component = "[state] " ERR component = "[error] " )
Component names for debug output
Variables ¶
var ErrInvalidQos = errors.New("Invalid QoS")
ErrInvalidQos is the error returned when an packet is to be sent with an invalid Qos value
var ErrInvalidTopicEmptyString = errors.New("Invalid Topic; empty string")
ErrInvalidTopicEmptyString is the error returned when a topic string is passed in that is 0 length
var ErrInvalidTopicMultilevel = errors.New("Invalid Topic; multi-level wildcard must be last level")
ErrInvalidTopicMultilevel is the error returned when a topic string is passed in that has the multi level wildcard in any position but the last
var ErrNotConnected = errors.New("Not Connected")
ErrNotConnected is the error returned from function calls that are made when the client is not connected to a broker
Functions ¶
func DefaultConnectionLostHandler ¶
DefaultConnectionLostHandler is a definition of a function that simply reports to the DEBUG log the reason for the client losing a connection.
Types ¶
type Client ¶
type Client interface { // IsConnected returns a bool signifying whether // the client is connected or not. IsConnected() bool // IsConnectionOpen return a bool signifying wether the client has an active // connection to mqtt broker, i.e not in disconnected or reconnect mode IsConnectionOpen() bool // Connect will create a connection to the message broker, by default // it will attempt to connect at v3.1.1 and auto retry at v3.1 if that // fails Connect() Token // Disconnect will end the connection with the server, but not before waiting // the specified number of milliseconds to wait for existing work to be // completed. Disconnect(quiesce uint) // Publish will publish a message with the specified QoS and content // to the specified topic. // Returns a token to track delivery of the message to the broker Publish(topic string, qos byte, retained bool, payload interface{}) Token // Subscribe starts a new subscription. Provide a MessageHandler to be executed when // a message is published on the topic provided, or nil for the default handler Subscribe(topic string, qos byte, callback MessageHandler) Token // SubscribeMultiple starts a new subscription for multiple topics. Provide a MessageHandler to // be executed when a message is published on one of the topics provided, or nil for the // default handler SubscribeMultiple(filters map[string]byte, callback MessageHandler) Token // Unsubscribe will end the subscription from each of the topics provided. // Messages published to those topics from other clients will no longer be // received. Unsubscribe(topics ...string) Token // AddRoute allows you to add a handler for messages on a specific topic // without making a subscription. For example having a different handler // for parts of a wildcard subscription AddRoute(topic string, callback MessageHandler) // OptionsReader returns a ClientOptionsReader which is a copy of the clientoptions // in use by the client. OptionsReader() ClientOptionsReader }
Client is the interface definition for a Client as used by this library, the interface is primarily to allow mocking tests.
It is an MQTT v3.1.1 client for communicating with an MQTT server using non-blocking methods that allow work to be done in the background. An application may connect to an MQTT server using:
A plain TCP socket A secure SSL/TLS socket A websocket
To enable ensured message delivery at Quality of Service (QoS) levels described in the MQTT spec, a message persistence mechanism must be used. This is done by providing a type which implements the Store interface. For convenience, FileStore and MemoryStore are provided implementations that should be sufficient for most use cases. More information can be found in their respective documentation. Numerous connection options may be specified by configuring a and then supplying a ClientOptions type.
func NewClient ¶
func NewClient(o *ClientOptions) Client
NewClient will create an MQTT v3.1.1 client with all of the options specified in the provided ClientOptions. The client must have the Connect method called on it before it may be used. This is to make sure resources (such as a net connection) are created before the application is actually ready.
type ClientOptions ¶
type ClientOptions struct { Servers []*url.URL ClientID string Username string Password string CredentialsProvider CredentialsProvider CleanSession bool Order bool WillEnabled bool WillTopic string WillPayload []byte WillQos byte WillRetained bool ProtocolVersion uint TLSConfig *tls.Config KeepAlive int64 PingTimeout time.Duration ConnectTimeout time.Duration MaxReconnectInterval time.Duration AutoReconnect bool Store Store DefaultPublishHandler MessageHandler OnConnect OnConnectHandler OnConnectionLost ConnectionLostHandler WriteTimeout time.Duration MessageChannelDepth uint ResumeSubs bool HTTPHeaders http.Header // contains filtered or unexported fields }
ClientOptions contains configurable options for an Client.
func NewClientOptions ¶
func NewClientOptions() *ClientOptions
NewClientOptions will create a new ClientClientOptions type with some default values.
Port: 1883 CleanSession: True Order: True KeepAlive: 30 (seconds) ConnectTimeout: 30 (seconds) MaxReconnectInterval 10 (minutes) AutoReconnect: True
func (*ClientOptions) AddBroker ¶
func (o *ClientOptions) AddBroker(server string) *ClientOptions
AddBroker adds a broker URI to the list of brokers to be used. The format should be scheme://host:port Where "scheme" is one of "tcp", "ssl", or "ws", "host" is the ip-address (or hostname) and "port" is the port on which the broker is accepting connections.
Default values for hostname is "127.0.0.1", for schema is "tcp://".
An example broker URI would look like: tcp://foobar.com:1883
func (*ClientOptions) SetAutoReconnect ¶
func (o *ClientOptions) SetAutoReconnect(a bool) *ClientOptions
SetAutoReconnect sets whether the automatic reconnection logic should be used when the connection is lost, even if disabled the ConnectionLostHandler is still called
func (*ClientOptions) SetBinaryWill ¶
func (o *ClientOptions) SetBinaryWill(topic string, payload []byte, qos byte, retained bool) *ClientOptions
SetBinaryWill accepts a []byte will message to be set. When the client connects, it will give this will message to the broker, which will then publish the provided payload (the will) to any clients that are subscribed to the provided topic.
func (*ClientOptions) SetCleanSession ¶
func (o *ClientOptions) SetCleanSession(clean bool) *ClientOptions
SetCleanSession will set the "clean session" flag in the connect message when this client connects to an MQTT broker. By setting this flag, you are indicating that no messages saved by the broker for this client should be delivered. Any messages that were going to be sent by this client before diconnecting previously but didn't will not be sent upon connecting to the broker.
func (*ClientOptions) SetClientID ¶
func (o *ClientOptions) SetClientID(id string) *ClientOptions
SetClientID will set the client id to be used by this client when connecting to the MQTT broker. According to the MQTT v3.1 specification, a client id mus be no longer than 23 characters.
func (*ClientOptions) SetConnectTimeout ¶
func (o *ClientOptions) SetConnectTimeout(t time.Duration) *ClientOptions
SetConnectTimeout limits how long the client will wait when trying to open a connection to an MQTT server before timeing out and erroring the attempt. A duration of 0 never times out. Default 30 seconds. Currently only operational on TCP/TLS connections.
func (*ClientOptions) SetConnectionLostHandler ¶
func (o *ClientOptions) SetConnectionLostHandler(onLost ConnectionLostHandler) *ClientOptions
SetConnectionLostHandler will set the OnConnectionLost callback to be executed in the case where the client unexpectedly loses connection with the MQTT broker.
func (*ClientOptions) SetCredentialsProvider ¶
func (o *ClientOptions) SetCredentialsProvider(p CredentialsProvider) *ClientOptions
SetCredentialsProvider will set a method to be called by this client when connecting to the MQTT broker that provide the current username and password. Note: without the use of SSL/TLS, this information will be sent in plaintext accross the wire.
func (*ClientOptions) SetDefaultPublishHandler ¶
func (o *ClientOptions) SetDefaultPublishHandler(defaultHandler MessageHandler) *ClientOptions
SetDefaultPublishHandler sets the MessageHandler that will be called when a message is received that does not match any known subscriptions.
func (*ClientOptions) SetHTTPHeaders ¶
func (o *ClientOptions) SetHTTPHeaders(h http.Header) *ClientOptions
SetHTTPHeaders sets the additional HTTP headers that will be sent in the WebSocket opening handshake.
func (*ClientOptions) SetKeepAlive ¶
func (o *ClientOptions) SetKeepAlive(k time.Duration) *ClientOptions
SetKeepAlive will set the amount of time (in seconds) that the client should wait before sending a PING request to the broker. This will allow the client to know that a connection has not been lost with the server.
func (*ClientOptions) SetMaxReconnectInterval ¶
func (o *ClientOptions) SetMaxReconnectInterval(t time.Duration) *ClientOptions
SetMaxReconnectInterval sets the maximum time that will be waited between reconnection attempts when connection is lost
func (*ClientOptions) SetMessageChannelDepth ¶
func (o *ClientOptions) SetMessageChannelDepth(s uint) *ClientOptions
SetMessageChannelDepth sets the size of the internal queue that holds messages while the client is temporairily offline, allowing the application to publish when the client is reconnecting. This setting is only valid if AutoReconnect is set to true, it is otherwise ignored.
func (*ClientOptions) SetOnConnectHandler ¶
func (o *ClientOptions) SetOnConnectHandler(onConn OnConnectHandler) *ClientOptions
SetOnConnectHandler sets the function to be called when the client is connected. Both at initial connection time and upon automatic reconnect.
func (*ClientOptions) SetOrderMatters ¶
func (o *ClientOptions) SetOrderMatters(order bool) *ClientOptions
SetOrderMatters will set the message routing to guarantee order within each QoS level. By default, this value is true. If set to false, this flag indicates that messages can be delivered asynchronously from the client to the application and possibly arrive out of order.
func (*ClientOptions) SetPassword ¶
func (o *ClientOptions) SetPassword(p string) *ClientOptions
SetPassword will set the password to be used by this client when connecting to the MQTT broker. Note: without the use of SSL/TLS, this information will be sent in plaintext accross the wire.
func (*ClientOptions) SetPingTimeout ¶
func (o *ClientOptions) SetPingTimeout(k time.Duration) *ClientOptions
SetPingTimeout will set the amount of time (in seconds) that the client will wait after sending a PING request to the broker, before deciding that the connection has been lost. Default is 10 seconds.
func (*ClientOptions) SetProtocolVersion ¶
func (o *ClientOptions) SetProtocolVersion(pv uint) *ClientOptions
SetProtocolVersion sets the MQTT version to be used to connect to the broker. Legitimate values are currently 3 - MQTT 3.1 or 4 - MQTT 3.1.1
func (*ClientOptions) SetResumeSubs ¶
func (o *ClientOptions) SetResumeSubs(resume bool) *ClientOptions
SetResumeSubs will enable resuming of stored (un)subscribe messages when connecting but not reconnecting if CleanSession is false. Otherwise these messages are discarded.
func (*ClientOptions) SetStore ¶
func (o *ClientOptions) SetStore(s Store) *ClientOptions
SetStore will set the implementation of the Store interface used to provide message persistence in cases where QoS levels QoS_ONE or QoS_TWO are used. If no store is provided, then the client will use MemoryStore by default.
func (*ClientOptions) SetTLSConfig ¶
func (o *ClientOptions) SetTLSConfig(t *tls.Config) *ClientOptions
SetTLSConfig will set an SSL/TLS configuration to be used when connecting to an MQTT broker. Please read the official Go documentation for more information.
func (*ClientOptions) SetUsername ¶
func (o *ClientOptions) SetUsername(u string) *ClientOptions
SetUsername will set the username to be used by this client when connecting to the MQTT broker. Note: without the use of SSL/TLS, this information will be sent in plaintext accross the wire.
func (*ClientOptions) SetWill ¶
func (o *ClientOptions) SetWill(topic string, payload string, qos byte, retained bool) *ClientOptions
SetWill accepts a string will message to be set. When the client connects, it will give this will message to the broker, which will then publish the provided payload (the will) to any clients that are subscribed to the provided topic.
func (*ClientOptions) SetWriteTimeout ¶
func (o *ClientOptions) SetWriteTimeout(t time.Duration) *ClientOptions
SetWriteTimeout puts a limit on how long a mqtt publish should block until it unblocks with a timeout error. A duration of 0 never times out. Default 30 seconds
func (*ClientOptions) UnsetWill ¶
func (o *ClientOptions) UnsetWill() *ClientOptions
UnsetWill will cause any set will message to be disregarded.
type ClientOptionsReader ¶
type ClientOptionsReader struct {
// contains filtered or unexported fields
}
ClientOptionsReader provides an interface for reading ClientOptions after the client has been initialized.
func (*ClientOptionsReader) AutoReconnect ¶
func (r *ClientOptionsReader) AutoReconnect() bool
func (*ClientOptionsReader) CleanSession ¶
func (r *ClientOptionsReader) CleanSession() bool
CleanSession returns whether Cleansession is set
func (*ClientOptionsReader) ClientID ¶
func (r *ClientOptionsReader) ClientID() string
ClientID returns the set client id
func (*ClientOptionsReader) ConnectTimeout ¶
func (r *ClientOptionsReader) ConnectTimeout() time.Duration
func (*ClientOptionsReader) HTTPHeaders ¶
func (r *ClientOptionsReader) HTTPHeaders() http.Header
func (*ClientOptionsReader) KeepAlive ¶
func (r *ClientOptionsReader) KeepAlive() time.Duration
func (*ClientOptionsReader) MaxReconnectInterval ¶
func (r *ClientOptionsReader) MaxReconnectInterval() time.Duration
func (*ClientOptionsReader) MessageChannelDepth ¶
func (r *ClientOptionsReader) MessageChannelDepth() uint
func (*ClientOptionsReader) Order ¶
func (r *ClientOptionsReader) Order() bool
func (*ClientOptionsReader) Password ¶
func (r *ClientOptionsReader) Password() string
Password returns the set password
func (*ClientOptionsReader) PingTimeout ¶
func (r *ClientOptionsReader) PingTimeout() time.Duration
func (*ClientOptionsReader) ProtocolVersion ¶
func (r *ClientOptionsReader) ProtocolVersion() uint
func (*ClientOptionsReader) ResumeSubs ¶
func (r *ClientOptionsReader) ResumeSubs() bool
ResumeSubs returns true if resuming stored (un)sub is enabled
func (*ClientOptionsReader) Servers ¶
func (r *ClientOptionsReader) Servers() []*url.URL
Servers returns a slice of the servers defined in the clientoptions
func (*ClientOptionsReader) TLSConfig ¶
func (r *ClientOptionsReader) TLSConfig() *tls.Config
func (*ClientOptionsReader) Username ¶
func (r *ClientOptionsReader) Username() string
Username returns the set username
func (*ClientOptionsReader) WillEnabled ¶
func (r *ClientOptionsReader) WillEnabled() bool
func (*ClientOptionsReader) WillPayload ¶
func (r *ClientOptionsReader) WillPayload() []byte
func (*ClientOptionsReader) WillQos ¶
func (r *ClientOptionsReader) WillQos() byte
func (*ClientOptionsReader) WillRetained ¶
func (r *ClientOptionsReader) WillRetained() bool
func (*ClientOptionsReader) WillTopic ¶
func (r *ClientOptionsReader) WillTopic() string
func (*ClientOptionsReader) WriteTimeout ¶
func (r *ClientOptionsReader) WriteTimeout() time.Duration
type ConnectToken ¶
type ConnectToken struct {
// contains filtered or unexported fields
}
ConnectToken is an extension of Token containing the extra fields required to provide information about calls to Connect()
func (*ConnectToken) ReturnCode ¶
func (c *ConnectToken) ReturnCode() byte
ReturnCode returns the acknowlegement code in the connack sent in response to a Connect()
func (*ConnectToken) SessionPresent ¶
func (c *ConnectToken) SessionPresent() bool
SessionPresent returns a bool representing the value of the session present field in the connack sent in response to a Connect()
func (*ConnectToken) Wait ¶
func (b *ConnectToken) Wait() bool
Wait will wait indefinitely for the Token to complete, ie the Publish to be sent and confirmed receipt from the broker
func (*ConnectToken) WaitTimeout ¶
WaitTimeout takes a time.Duration to wait for the flow associated with the Token to complete, returns true if it returned before the timeout or returns false if the timeout occurred. In the case of a timeout the Token does not have an error set in case the caller wishes to wait again
type ConnectionLostHandler ¶
ConnectionLostHandler is a callback type which can be set to be executed upon an unintended disconnection from the MQTT broker. Disconnects caused by calling Disconnect or ForceDisconnect will not cause an OnConnectionLost callback to execute.
type CredentialsProvider ¶
CredentialsProvider allows the username and password to be updated before reconnecting. It should return the current username and password.
type DisconnectToken ¶
type DisconnectToken struct {
// contains filtered or unexported fields
}
DisconnectToken is an extension of Token containing the extra fields required to provide information about calls to Disconnect()
func (*DisconnectToken) Wait ¶
func (b *DisconnectToken) Wait() bool
Wait will wait indefinitely for the Token to complete, ie the Publish to be sent and confirmed receipt from the broker
func (*DisconnectToken) WaitTimeout ¶
WaitTimeout takes a time.Duration to wait for the flow associated with the Token to complete, returns true if it returned before the timeout or returns false if the timeout occurred. In the case of a timeout the Token does not have an error set in case the caller wishes to wait again
type DummyToken ¶
type DummyToken struct {
// contains filtered or unexported fields
}
func (*DummyToken) Error ¶
func (d *DummyToken) Error() error
func (*DummyToken) Wait ¶
func (d *DummyToken) Wait() bool
func (*DummyToken) WaitTimeout ¶
func (d *DummyToken) WaitTimeout(t time.Duration) bool
type FileStore ¶
FileStore implements the store interface using the filesystem to provide true persistence, even across client failure. This is designed to use a single directory per running client. If you are running multiple clients on the same filesystem, you will need to be careful to specify unique store directories for each.
func NewFileStore ¶
NewFileStore will create a new FileStore which stores its messages in the directory provided.
func (*FileStore) All ¶
All will provide a list of all of the keys associated with messages currenly residing in the FileStore.
func (*FileStore) Close ¶
func (store *FileStore) Close()
Close will disallow the FileStore from being used.
func (*FileStore) Del ¶
Del will remove the persisted message associated with the provided key from the FileStore.
func (*FileStore) Get ¶
func (store *FileStore) Get(key string) packets.ControlPacket
Get will retrieve a message from the store, the one associated with the provided key value.
type Logger ¶
type Logger interface { Println(v ...interface{}) Printf(format string, v ...interface{}) }
Logger interface allows implementations to provide to this package any object that implements the methods defined in it.
var ( ERROR Logger = NOOPLogger{} CRITICAL Logger = NOOPLogger{} WARN Logger = NOOPLogger{} DEBUG Logger = NOOPLogger{} )
Internal levels of library output that are initialised to not print anything but can be overridden by programmer
type MId ¶
type MId uint16
MId is 16 bit message id as specified by the MQTT spec. In general, these values should not be depended upon by the client application.
type MemoryStore ¶
MemoryStore implements the store interface to provide a "persistence" mechanism wholly stored in memory. This is only useful for as long as the client instance exists.
func NewMemoryStore ¶
func NewMemoryStore() *MemoryStore
NewMemoryStore returns a pointer to a new instance of MemoryStore, the instance is not initialized and ready to use until Open() has been called on it.
func (*MemoryStore) All ¶
func (store *MemoryStore) All() []string
All returns a slice of strings containing all the keys currently in the MemoryStore.
func (*MemoryStore) Close ¶
func (store *MemoryStore) Close()
Close will disallow modifications to the state of the store.
func (*MemoryStore) Del ¶
func (store *MemoryStore) Del(key string)
Del takes a key, searches the MemoryStore and if the key is found deletes the Message pointer associated with it.
func (*MemoryStore) Get ¶
func (store *MemoryStore) Get(key string) packets.ControlPacket
Get takes a key and looks in the store for a matching Message returning either the Message pointer or nil.
func (*MemoryStore) Open ¶
func (store *MemoryStore) Open()
Open initializes a MemoryStore instance.
func (*MemoryStore) Put ¶
func (store *MemoryStore) Put(key string, message packets.ControlPacket)
Put takes a key and a pointer to a Message and stores the message.
func (*MemoryStore) Reset ¶
func (store *MemoryStore) Reset()
Reset eliminates all persisted message data in the store.
type Message ¶
type Message interface { Duplicate() bool Qos() byte Retained() bool Topic() string MessageID() uint16 Payload() []byte Ack() }
Message defines the externals that a message implementation must support these are received messages that are passed to the callbacks, not internal messages
type MessageHandler ¶
MessageHandler is a callback type which can be set to be executed upon the arrival of messages published to topics to which the client is subscribed.
type NOOPLogger ¶
type NOOPLogger struct{}
NOOPLogger implements the logger that does not perform any operation by default. This allows us to efficiently discard the unwanted messages.
func (NOOPLogger) Printf ¶
func (NOOPLogger) Printf(format string, v ...interface{})
func (NOOPLogger) Println ¶
func (NOOPLogger) Println(v ...interface{})
type OnConnectHandler ¶
type OnConnectHandler func(Client)
OnConnectHandler is a callback that is called when the client state changes from unconnected/disconnected to connected. Both at initial connection and on reconnection
type PacketAndToken ¶
type PacketAndToken struct {
// contains filtered or unexported fields
}
PacketAndToken is a struct that contains both a ControlPacket and a Token. This struct is passed via channels between the client interface code and the underlying code responsible for sending and receiving MQTT messages.
type PublishToken ¶
type PublishToken struct {
// contains filtered or unexported fields
}
PublishToken is an extension of Token containing the extra fields required to provide information about calls to Publish()
func (*PublishToken) MessageID ¶
func (p *PublishToken) MessageID() uint16
MessageID returns the MQTT message ID that was assigned to the Publish packet when it was sent to the broker
func (*PublishToken) Wait ¶
func (b *PublishToken) Wait() bool
Wait will wait indefinitely for the Token to complete, ie the Publish to be sent and confirmed receipt from the broker
func (*PublishToken) WaitTimeout ¶
WaitTimeout takes a time.Duration to wait for the flow associated with the Token to complete, returns true if it returned before the timeout or returns false if the timeout occurred. In the case of a timeout the Token does not have an error set in case the caller wishes to wait again
type Store ¶
type Store interface { Open() Put(key string, message packets.ControlPacket) Get(key string) packets.ControlPacket All() []string Del(key string) Close() Reset() }
Store is an interface which can be used to provide implementations for message persistence. Because we may have to store distinct messages with the same message ID, we need a unique key for each message. This is possible by prepending "i." or "o." to each message id
type SubscribeToken ¶
type SubscribeToken struct {
// contains filtered or unexported fields
}
SubscribeToken is an extension of Token containing the extra fields required to provide information about calls to Subscribe()
func (*SubscribeToken) Result ¶
func (s *SubscribeToken) Result() map[string]byte
Result returns a map of topics that were subscribed to along with the matching return code from the broker. This is either the Qos value of the subscription or an error code.
func (*SubscribeToken) Wait ¶
func (b *SubscribeToken) Wait() bool
Wait will wait indefinitely for the Token to complete, ie the Publish to be sent and confirmed receipt from the broker
func (*SubscribeToken) WaitTimeout ¶
WaitTimeout takes a time.Duration to wait for the flow associated with the Token to complete, returns true if it returned before the timeout or returns false if the timeout occurred. In the case of a timeout the Token does not have an error set in case the caller wishes to wait again
type Token ¶
Token defines the interface for the tokens used to indicate when actions have completed.
type TokenErrorSetter ¶
type TokenErrorSetter interface {
// contains filtered or unexported methods
}
type UnsubscribeToken ¶
type UnsubscribeToken struct {
// contains filtered or unexported fields
}
UnsubscribeToken is an extension of Token containing the extra fields required to provide information about calls to Unsubscribe()
func (*UnsubscribeToken) Wait ¶
func (b *UnsubscribeToken) Wait() bool
Wait will wait indefinitely for the Token to complete, ie the Publish to be sent and confirmed receipt from the broker
func (*UnsubscribeToken) WaitTimeout ¶
WaitTimeout takes a time.Duration to wait for the flow associated with the Token to complete, returns true if it returned before the timeout or returns false if the timeout occurred. In the case of a timeout the Token does not have an error set in case the caller wishes to wait again