Documentation
¶
Overview ¶
Package proxy is middleware that proxies HTTP requests.
Index ¶
Constants ¶
const CustomStatusContextCancelled = 499
Variables ¶
This section is empty.
Functions ¶
func RegisterPolicy ¶
RegisterPolicy adds a custom policy to the proxy.
Types ¶
type First ¶ added in v0.10.0
type First struct{}
First is a policy that selects the first available host
type Header ¶ added in v0.10.5
type Header struct {
// The name of the request header, the value of which will determine
// how the request is routed
Name string
}
Header is a policy that selects based on a hash of the given header
type IPHash ¶ added in v0.9.1
type IPHash struct{}
IPHash is a policy that selects hosts based on hashing the request IP
type LeastConn ¶
type LeastConn struct{}
LeastConn is a policy that selects the host with the least connections.
type Policy ¶
type Policy interface {
Select(pool HostPool, r *http.Request) *UpstreamHost
}
Policy decides how a host will be selected from a pool.
type Proxy ¶
type Proxy struct {
Next httpserver.Handler
Upstreams []Upstream
}
Proxy represents a middleware instance that can proxy requests.
type ReverseProxy ¶
type ReverseProxy struct {
// Director must be a function which modifies
// the request into a new request to be sent
// using Transport. Its response is then copied
// back to the original client unmodified.
Director func(*http.Request)
// The transport used to perform proxy requests.
Transport http.RoundTripper
// FlushInterval specifies the flush interval
// to flush to the client while copying the
// response body.
// If zero, no periodic flushing is done.
FlushInterval time.Duration
// contains filtered or unexported fields
}
ReverseProxy is an HTTP Handler that takes an incoming request and sends it to another server, proxying the response back to the client.
func NewSingleHostReverseProxy ¶
func NewSingleHostReverseProxy(target *url.URL, without string, keepalive int, timeout, fallbackDelay time.Duration) *ReverseProxy
NewSingleHostReverseProxy returns a new ReverseProxy that rewrites URLs to the scheme, host, and base path provided in target. If the target's path is "/base" and the incoming request was for "/dir", the target request will be for /base/dir. Without logic: target's path is "/", incoming is "/api/messages", without is "/api", then the target request will be for /messages.
func (*ReverseProxy) ServeHTTP ¶
func (rp *ReverseProxy) ServeHTTP(rw http.ResponseWriter, outreq *http.Request, respUpdateFn respUpdateFn) error
ServeHTTP serves the proxied request to the upstream by performing a roundtrip. It is designed to handle websocket connection upgrades as well.
func (*ReverseProxy) UseInsecureTransport ¶ added in v0.9.1
func (rp *ReverseProxy) UseInsecureTransport()
UseInsecureTransport is used to facilitate HTTPS proxying when it is OK for upstream to be using a bad certificate, since this transport skips verification.
type RoundRobin ¶
type RoundRobin struct {
// contains filtered or unexported fields
}
RoundRobin is a policy that selects hosts based on round-robin ordering.
func (*RoundRobin) Select ¶
func (r *RoundRobin) Select(pool HostPool, request *http.Request) *UpstreamHost
Select selects an up host from the pool using a round-robin ordering scheme.
type URIHash ¶ added in v0.10.3
type URIHash struct{}
URIHash is a policy that selects the host based on hashing the request URI
type Upstream ¶
type Upstream interface {
// The path this upstream host should be routed on
From() string
// Selects an upstream host to be routed to. It
// should return a suitable upstream host, or nil
// if no such hosts are available.
Select(*http.Request) *UpstreamHost
// Checks if subpath is not an ignored path
AllowedPath(string) bool
// Gets the duration of the headstart the first
// connection is given in the Go standard library's
// implementation of "Happy Eyeballs" when DualStack
// is enabled in net.Dialer.
GetFallbackDelay() time.Duration
// Gets how long to try selecting upstream hosts
// in the case of cascading failures.
GetTryDuration() time.Duration
// Gets how long to wait between selecting upstream
// hosts in the case of cascading failures.
GetTryInterval() time.Duration
// Gets the number of upstream hosts.
GetHostCount() int
// Gets how long to wait before timing out
// the request
GetTimeout() time.Duration
// Stops the upstream from proxying requests to shutdown goroutines cleanly.
Stop() error
}
Upstream manages a pool of proxy upstream hosts.
func NewStaticUpstreams ¶
NewStaticUpstreams parses the configuration input and sets up static upstreams for the proxy middleware. The host string parameter, if not empty, is used for setting the upstream Host header for the health checks if the upstream header config requires it.
type UpstreamHost ¶
type UpstreamHost struct {
// This field is read & written to concurrently, so all access must use
// atomic operations.
Conns int64 // must be first field to be 64-bit aligned on 32-bit systems
MaxConns int64
Name string // hostname of this upstream host
UpstreamHeaders http.Header
DownstreamHeaders http.Header
FailTimeout time.Duration
CheckDown UpstreamHostDownFunc
WithoutPathPrefix string
ReverseProxy *ReverseProxy
Fails int32
// This is an int32 so that we can use atomic operations to do concurrent
// reads & writes to this value. The default value of 0 indicates that it
// is healthy and any non-zero value indicates unhealthy.
Unhealthy int32
HealthCheckResult atomic.Value
}
UpstreamHost represents a single proxy upstream
func (*UpstreamHost) Available ¶
func (uh *UpstreamHost) Available() bool
Available checks whether the upstream host is available for proxying to
func (*UpstreamHost) Down ¶
func (uh *UpstreamHost) Down() bool
Down checks whether the upstream host is down or not. Down will try to use uh.CheckDown first, and will fall back to some default criteria if necessary.
func (*UpstreamHost) Full ¶
func (uh *UpstreamHost) Full() bool
Full checks whether the upstream host has reached its maximum connections
type UpstreamHostDownFunc ¶
type UpstreamHostDownFunc func(*UpstreamHost) bool
UpstreamHostDownFunc can be used to customize how Down behaves.
Source Files