83 lines
2.4 KiB
Go
83 lines
2.4 KiB
Go
// Package mhttp extends the standard package with extra functionality which is
|
|
// commonly useful
|
|
package mhttp
|
|
|
|
import (
|
|
"context"
|
|
"net"
|
|
"net/http"
|
|
"net/http/httputil"
|
|
"net/url"
|
|
"strings"
|
|
|
|
"github.com/mediocregopher/mediocre-go-lib/m"
|
|
"github.com/mediocregopher/mediocre-go-lib/mcfg"
|
|
"github.com/mediocregopher/mediocre-go-lib/mlog"
|
|
"github.com/mediocregopher/mediocre-go-lib/mnet"
|
|
)
|
|
|
|
// CfgServer initializes and returns an *http.Server which will initialize on
|
|
// the Start hook. This also sets up config params for configuring the address
|
|
// being listened on.
|
|
func CfgServer(cfg *mcfg.Cfg, h http.Handler) *http.Server {
|
|
cfg = cfg.Child("http")
|
|
addr := cfg.ParamString("addr", ":0", "Address to listen on. Default is any open port")
|
|
|
|
srv := http.Server{Handler: h}
|
|
cfg.Start.Then(func(ctx context.Context) error {
|
|
srv.Addr = *addr
|
|
kv := mlog.KV{"addr": *addr}
|
|
log := m.Log(cfg, kv)
|
|
log.Info("listening")
|
|
go func() {
|
|
err := srv.ListenAndServe()
|
|
// TODO the listening log should happen here, somehow, now that we
|
|
// know the actual address being listened on
|
|
log.Fatal("http server fataled", mlog.ErrKV(err))
|
|
}()
|
|
return nil
|
|
})
|
|
|
|
// TODO shutdown logic
|
|
return &srv
|
|
}
|
|
|
|
// AddXForwardedFor populates the X-Forwarded-For header on the Request to
|
|
// convey that the request is being proxied for IP.
|
|
//
|
|
// If the IP is invalid, loopback, or otherwise part of a reserved range, this
|
|
// does nothing.
|
|
func AddXForwardedFor(r *http.Request, ipStr string) {
|
|
const xff = "X-Forwarded-For"
|
|
ip := net.ParseIP(ipStr)
|
|
if ip == nil || mnet.IsReservedIP(ip) { // IsReservedIP includes loopback
|
|
return
|
|
}
|
|
prev, _ := r.Header[xff]
|
|
r.Header.Set(xff, strings.Join(append(prev, ip.String()), ", "))
|
|
}
|
|
|
|
// ReverseProxy returns an httputil.ReverseProxy which will send requests to the
|
|
// given URL and copy their responses back without modification.
|
|
//
|
|
// Only the Scheme and Host of the given URL are used.
|
|
//
|
|
// Any http.ResponseWriters passed into the ServeHTTP call of the returned
|
|
// instance should not be modified afterwards.
|
|
func ReverseProxy(u *url.URL) *httputil.ReverseProxy {
|
|
rp := new(httputil.ReverseProxy)
|
|
rp.Director = func(req *http.Request) {
|
|
if ipStr, _, err := net.SplitHostPort(req.RemoteAddr); err != nil {
|
|
AddXForwardedFor(req, ipStr)
|
|
}
|
|
|
|
req.URL.Scheme = u.Scheme
|
|
req.URL.Host = u.Host
|
|
}
|
|
|
|
// TODO when this package has a function for creating a Client use that for
|
|
// the default here
|
|
|
|
return rp
|
|
}
|