Documentation ¶
Overview ¶
Package proxy is middleware that proxies HTTP requests.
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func RegisterPolicy ¶
RegisterPolicy adds a custom policy to the proxy.
Types ¶
type Header ¶
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 ¶
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. // If nil, http.DefaultTransport is used. 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 }
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) *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 ¶
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 ¶
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 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 // 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 }
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.