Documentation ¶
Overview ¶
Package plugin provides some types and functions common among plugin.
Index ¶
- Constants
- Variables
- func A(b ServiceBackend, zone string, state request.Request, previousRecords []dns.RR, ...) (records []dns.RR, err error)
- func AAAA(b ServiceBackend, zone string, state request.Request, previousRecords []dns.RR, ...) (records []dns.RR, err error)
- func BackendError(b ServiceBackend, zone string, rcode int, state request.Request, err error, ...) (int, error)
- func CNAME(b ServiceBackend, zone string, state request.Request, opt Options) (records []dns.RR, err error)
- func ClientWrite(rcode int) bool
- func Error(name string, err error) error
- func MX(b ServiceBackend, zone string, state request.Request, opt Options) (records, extra []dns.RR, err error)
- func NS(b ServiceBackend, zone string, state request.Request, opt Options) (records, extra []dns.RR, err error)
- func NextOrFailure(name string, next Handler, ctx context.Context, w dns.ResponseWriter, ...) (int, error)
- func PTR(b ServiceBackend, zone string, state request.Request, opt Options) (records []dns.RR, err error)
- func SOA(b ServiceBackend, zone string, state request.Request, opt Options) ([]dns.RR, error)
- func SRV(b ServiceBackend, zone string, state request.Request, opt Options) (records, extra []dns.RR, err error)
- func SplitHostPort(s string) (host, port string, ipnet *net.IPNet, err error)
- func TXT(b ServiceBackend, zone string, state request.Request, opt Options) (records []dns.RR, err error)
- type Handler
- type HandlerFunc
- type Host
- type Name
- type Options
- type Plugin
- type ServerCtx
- type ServiceBackend
- type Transferer
- type Zones
Constants ¶
const ( TransportDNS = "dns" TransportTLS = "tls" TransportGRPC = "grpc" )
Duplicated from core/dnsserver/address.go !
const Namespace = "coredns"
Namespace is the namespace used for the metrics.
Variables ¶
var ErrOnce = errors.New("this plugin can only be used once per Server Block")
ErrOnce is returned when a plugin doesn't support multiple setups per server.
var TimeBuckets = prometheus.ExponentialBuckets(0.00025, 2, 16) // from 0.25ms to 8 seconds
TimeBuckets is based on Prometheus client_golang prometheus.DefBuckets
Functions ¶
func A ¶
func A(b ServiceBackend, zone string, state request.Request, previousRecords []dns.RR, opt Options) (records []dns.RR, err error)
A returns A records from Backend or an error.
func AAAA ¶
func AAAA(b ServiceBackend, zone string, state request.Request, previousRecords []dns.RR, opt Options) (records []dns.RR, err error)
AAAA returns AAAA records from Backend or an error.
func BackendError ¶
func BackendError(b ServiceBackend, zone string, rcode int, state request.Request, err error, opt Options) (int, error)
BackendError writes an error response to the client.
func CNAME ¶
func CNAME(b ServiceBackend, zone string, state request.Request, opt Options) (records []dns.RR, err error)
CNAME returns CNAME records from the backend or an error.
func ClientWrite ¶
ClientWrite returns true if the response has been written to the client. Each plugin to adhire to this protocol.
func MX ¶
func MX(b ServiceBackend, zone string, state request.Request, opt Options) (records, extra []dns.RR, err error)
MX returns MX records from the Backend. If the Target is not a name but an IP address, a name is created on the fly.
func NS ¶
func NS(b ServiceBackend, zone string, state request.Request, opt Options) (records, extra []dns.RR, err error)
NS returns NS records from the backend
func NextOrFailure ¶
func NextOrFailure(name string, next Handler, ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error)
NextOrFailure calls next.ServeDNS when next is not nill, otherwise it will return, a ServerFailure and a nil error.
func PTR ¶
func PTR(b ServiceBackend, zone string, state request.Request, opt Options) (records []dns.RR, err error)
PTR returns the PTR records from the backend, only services that have a domain name as host are included.
func SRV ¶
func SRV(b ServiceBackend, zone string, state request.Request, opt Options) (records, extra []dns.RR, err error)
SRV returns SRV records from the Backend. If the Target is not a name but an IP address, a name is created on the fly.
func SplitHostPort ¶
SplitHostPort splits s up in a host and port portion, taking reverse address notation into account. String the string s should *not* be prefixed with any protocols, i.e. dns://. The returned ipnet is the *net.IPNet that is used when the zone is a reverse and a netmask is given.
Types ¶
type Handler ¶
type Handler interface { ServeDNS(context.Context, dns.ResponseWriter, *dns.Msg) (int, error) Name() string }
Handler is like dns.Handler except ServeDNS may return an rcode and/or error.
If ServeDNS writes to the response body, it should return a status code. If the status code is not one of the following:
* SERVFAIL (dns.RcodeServerFailure)
* REFUSED (dns.RecodeRefused)
* FORMERR (dns.RcodeFormatError)
* NOTIMP (dns.RcodeNotImplemented)
CoreDNS assumes *no* reply has yet been written. All other response codes signal other handlers above it that the response message is already written, and that they should not write to it also.
If ServeDNS encounters an error, it should return the error value so it can be logged by designated error-handling plugin.
If writing a response after calling another ServeDNS method, the returned rcode SHOULD be used when writing the response.
If handling errors after calling another ServeDNS method, the returned error value SHOULD be logged or handled accordingly.
Otherwise, return values should be propagated down the plugin chain by returning them unchanged.
type HandlerFunc ¶
HandlerFunc is a convenience type like dns.HandlerFunc, except ServeDNS returns an rcode and an error. See Handler documentation for more information.
type Name ¶
type Name string
Name represents a domain name.
type Plugin ¶
Plugin is a middle layer which represents the traditional idea of plugin: it chains one Handler to the next by being passed the next Handler in the chain.
type ServerCtx ¶
type ServerCtx struct{}
ServerCtx is the context key to pass server address context to the plugins handling the request.
type ServiceBackend ¶
type ServiceBackend interface { // Services communicates with the backend to retrieve the service definitions. Exact indicates // on exact match should be returned. Services(state request.Request, exact bool, opt Options) ([]msg.Service, error) // Reverse communicates with the backend to retrieve service definition based on a IP address // instead of a name. I.e. a reverse DNS lookup. Reverse(state request.Request, exact bool, opt Options) ([]msg.Service, error) // Lookup is used to find records else where. Lookup(state request.Request, name string, typ uint16) (*dns.Msg, error) // Returns _all_ services that matches a certain name. // Note: it does not implement a specific service. Records(state request.Request, exact bool) ([]msg.Service, error) // IsNameError return true if err indicated a record not found condition IsNameError(err error) bool Transferer }
ServiceBackend defines a (dynamic) backend that returns a slice of service definitions.
type Transferer ¶
type Transferer interface { // Serial returns a SOA serial number to construct a SOA record. Serial(state request.Request) uint32 // MinTTL returns the minimum TTL to be used in the SOA record. MinTTL(state request.Request) uint32 // Transfer handles a zone transfer it writes to the client just // like any other handler. Transfer(ctx context.Context, state request.Request) (int, error) }
Transferer defines an interface for backends that provide AXFR of all records.
Directories ¶
Path | Synopsis |
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Package auto implements an on-the-fly loading file backend.
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Package auto implements an on-the-fly loading file backend. |
Package autopath implements autopathing.
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Package autopath implements autopathing. |
Package bind allows binding to a specific interface instead of bind to all of them.
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Package bind allows binding to a specific interface instead of bind to all of them. |
Package cache implements a cache.
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Package cache implements a cache. |
freq
Package freq keeps track of last X seen events.
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Package freq keeps track of last X seen events. |
Package chaos implements a plugin that answer to 'CH version.bind TXT' type queries.
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Package chaos implements a plugin that answer to 'CH version.bind TXT' type queries. |
Package deprecated is used when we deprecated plugin.
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Package deprecated is used when we deprecated plugin. |
Package dnssec implements a plugin that signs responses on-the-fly using NSEC black lies.
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Package dnssec implements a plugin that signs responses on-the-fly using NSEC black lies. |
taprw
Package taprw takes a query and intercepts the response.
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Package taprw takes a query and intercepts the response. |
Package erratic implements a plugin that returns erratic answers (delayed, dropped).
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Package erratic implements a plugin that returns erratic answers (delayed, dropped). |
Package errors implements an HTTP error handling plugin.
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Package errors implements an HTTP error handling plugin. |
Package etcd provides the etcd backend plugin.
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Package etcd provides the etcd backend plugin. |
msg
Package msg defines the Service structure which is used for service discovery.
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Package msg defines the Service structure which is used for service discovery. |
Package federation implements kubernetes federation.
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Package federation implements kubernetes federation. |
Package file implements a file backend.
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Package file implements a file backend. |
tree
Package tree implements Left-Leaning Red Black trees as described by Robert Sedgewick.
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Package tree implements Left-Leaning Red Black trees as described by Robert Sedgewick. |
Package forward implements a forwarding proxy.
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Package forward implements a forwarding proxy. |
Package health implements an HTTP handler that responds to health checks.
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Package health implements an HTTP handler that responds to health checks. |
Package kubernetes provides the kubernetes backend.
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Package kubernetes provides the kubernetes backend. |
Package loadbalance is plugin for rewriting responses to do "load balancing" Package loadbalance shuffles A and AAAA records.
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Package loadbalance is plugin for rewriting responses to do "load balancing" Package loadbalance shuffles A and AAAA records. |
Package log implements basic but useful request (access) logging plugin.
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Package log implements basic but useful request (access) logging plugin. |
Package metrics implement a handler and plugin that provides Prometheus metrics.
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Package metrics implement a handler and plugin that provides Prometheus metrics. |
test
Package test will scrape a target and you can inspect the variables.
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Package test will scrape a target and you can inspect the variables. |
Package nsid implements NSID protocol
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Package nsid implements NSID protocol |
pkg
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cache
Package cache implements a cache.
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Package cache implements a cache. |
dnstest
Package dnstest allows for easy testing of DNS client against a test server.
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Package dnstest allows for easy testing of DNS client against a test server. |
dnsutil
Package dnsutil contains DNS related helper functions.
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Package dnsutil contains DNS related helper functions. |
edns
Package edns provides function useful for adding/inspecting OPT records to/in messages.
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Package edns provides function useful for adding/inspecting OPT records to/in messages. |
fall
Package fall handles the fallthrough logic used in plugins that support it.
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Package fall handles the fallthrough logic used in plugins that support it. |
fuzz
Package fuzz contains functions that enable fuzzing of plugins.
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Package fuzz contains functions that enable fuzzing of plugins. |
log
Package log implements a small wrapper around the std lib log package.
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Package log implements a small wrapper around the std lib log package. |
nonwriter
Package nonwriter implements a dns.ResponseWriter that never writes, but captures the dns.Msg being written.
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Package nonwriter implements a dns.ResponseWriter that never writes, but captures the dns.Msg being written. |
parse
Package parse contains functions that can be used in the setup code for plugins.
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Package parse contains functions that can be used in the setup code for plugins. |
singleflight
Package singleflight provides a duplicate function call suppression mechanism.
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Package singleflight provides a duplicate function call suppression mechanism. |
up
Package up is used to run a function for some duration.
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Package up is used to run a function for some duration. |
upstream
Package upstream abstracts a upstream lookups so that plugins can handle them in an unified way.
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Package upstream abstracts a upstream lookups so that plugins can handle them in an unified way. |
Package pprof implement a debug endpoint for getting profiles using the go pprof tooling.
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Package pprof implement a debug endpoint for getting profiles using the go pprof tooling. |
Package proxy is plugin that proxies requests.
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Package proxy is plugin that proxies requests. |
Package rewrite is plugin for rewriting requests internally to something different.
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Package rewrite is plugin for rewriting requests internally to something different. |
Package route53 implements a plugin that returns resource records from AWS route53
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Package route53 implements a plugin that returns resource records from AWS route53 |
Package secondary implements a secondary plugin.
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Package secondary implements a secondary plugin. |
Package test contains helper functions for writing plugin tests.
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Package test contains helper functions for writing plugin tests. |
Package trace implements OpenTracing-based tracing
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Package trace implements OpenTracing-based tracing |
Package whoami implements a plugin that returns details about the resolving querying it.
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Package whoami implements a plugin that returns details about the resolving querying it. |