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Oxy [](https://travis-ci.org/vulcand/oxy)
=====
Oxy is a Go library with HTTP handlers that enhance HTTP standard library:
* [Buffer](https://pkg.go.dev/github.com/vulcand/oxy/buffer) retries and buffers requests and responses
* [Stream](https://pkg.go.dev/github.com/vulcand/oxy/stream) passes-through requests, supports chunked encoding with configurable flush interval
* [Forward](https://pkg.go.dev/github.com/vulcand/oxy/forward) forwards requests to remote location and rewrites headers
* [Roundrobin](https://pkg.go.dev/github.com/vulcand/oxy/roundrobin) is a round-robin load balancer
* [Circuit Breaker](https://pkg.go.dev/github.com/vulcand/oxy/cbreaker) Hystrix-style circuit breaker
* [Connlimit](https://pkg.go.dev/github.com/vulcand/oxy/connlimit) Simultaneous connections limiter
* [Ratelimit](https://pkg.go.dev/github.com/vulcand/oxy/ratelimit) Rate limiter (based on tokenbucket algo)
* [Trace](https://pkg.go.dev/github.com/vulcand/oxy/trace) Structured request and response logger
It is designed to be fully compatible with http standard library, easy to customize and reuse.
Status
------
* Initial design is completed
* Covered by tests
* Used as a reverse proxy engine in [Vulcand](https://github.com/vulcand/vulcand)
Quickstart
-----------
Every handler is ``http.Handler``, so writing and plugging in a middleware is easy. Let us write a simple reverse proxy as an example:
Simple reverse proxy
====================
```go
import (
"net/http"
"github.com/vulcand/oxy/v2/forward"
"github.com/vulcand/oxy/v2/testutils"
)
// Forwards incoming requests to whatever location URL points to, adds proper forwarding headers
fwd := forward.New(false)
redirect := http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
// let us forward this request to another server
req.URL = testutils.ParseURI("http://localhost:63450")
fwd.ServeHTTP(w, req)
})
// that's it! our reverse proxy is ready!
s := &http.Server{
Addr: ":8080",
Handler: redirect,
}
s.ListenAndServe()
```
As a next step, let us add a round robin load-balancer:
```go
import (
"net/http"
"github.com/vulcand/oxy/v2/forward"
"github.com/vulcand/oxy/v2/roundrobin"
)
// Forwards incoming requests to whatever location URL points to, adds proper forwarding headers
fwd := forward.New(false)
lb, _ := roundrobin.New(fwd)
lb.UpsertServer(url1)
lb.UpsertServer(url2)
s := &http.Server{
Addr: ":8080",
Handler: lb,
}
s.ListenAndServe()
```
What if we want to handle retries and replay the request in case of errors? `buffer` handler will help:
```go
import (
"net/http"
"github.com/vulcand/oxy/v2/forward"
"github.com/vulcand/oxy/v2/buffer"
"github.com/vulcand/oxy/v2/roundrobin"
)
// Forwards incoming requests to whatever location URL points to, adds proper forwarding headers
fwd := forward.New(false)
lb, _ := roundrobin.New(fwd)
// buffer will read the request body and will replay the request again in case if forward returned status
// corresponding to nework error (e.g. Gateway Timeout)
buffer, _ := buffer.New(lb, buffer.Retry(`IsNetworkError() && Attempts() < 2`))
lb.UpsertServer(url1)
lb.UpsertServer(url2)
// that's it! our reverse proxy is ready!
s := &http.Server{
Addr: ":8080",
Handler: buffer,
}
s.ListenAndServe()
```
|
