Files
reproxy/vendor/github.com/go-pkgz/rest/middleware.go

93 lines
2.4 KiB
Go

package rest
import (
"net/http"
"os"
"runtime/debug"
"strings"
"github.com/go-pkgz/rest/logger"
)
// Wrap converts a list of middlewares to nested calls (in reverse order)
func Wrap(handler http.Handler, mws ...func(http.Handler) http.Handler) http.Handler {
if len(mws) == 0 {
return handler
}
res := handler
for i := len(mws) - 1; i >= 0; i-- {
res = mws[i](res)
}
return res
}
// AppInfo adds custom app-info to the response header
func AppInfo(app, author, version string) func(http.Handler) http.Handler {
f := func(h http.Handler) http.Handler {
fn := func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Author", author)
w.Header().Set("App-Name", app)
w.Header().Set("App-Version", version)
if mhost := os.Getenv("MHOST"); mhost != "" {
w.Header().Set("Host", mhost)
}
h.ServeHTTP(w, r)
}
return http.HandlerFunc(fn)
}
return f
}
// Ping middleware response with pong to /ping. Stops chain if ping request detected
func Ping(next http.Handler) http.Handler {
fn := func(w http.ResponseWriter, r *http.Request) {
if r.Method == "GET" && strings.HasSuffix(strings.ToLower(r.URL.Path), "/ping") {
w.Header().Set("Content-Type", "text/plain")
w.WriteHeader(http.StatusOK)
_, _ = w.Write([]byte("pong"))
return
}
next.ServeHTTP(w, r)
}
return http.HandlerFunc(fn)
}
// Recoverer is a middleware that recovers from panics, logs the panic and returns a HTTP 500 status if possible.
func Recoverer(l logger.Backend) func(http.Handler) http.Handler {
return func(h http.Handler) http.Handler {
fn := func(w http.ResponseWriter, r *http.Request) {
defer func() {
if rvr := recover(); rvr != nil {
l.Logf("request panic for %s from %s, %v", r.URL.String(), r.RemoteAddr, rvr)
if rvr != http.ErrAbortHandler {
l.Logf(string(debug.Stack()))
}
http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
}
}()
h.ServeHTTP(w, r)
}
return http.HandlerFunc(fn)
}
}
// Headers middleware adds headers to request
func Headers(headers ...string) func(http.Handler) http.Handler {
return func(h http.Handler) http.Handler {
fn := func(w http.ResponseWriter, r *http.Request) {
for _, h := range headers {
elems := strings.Split(h, ":")
if len(elems) != 2 {
continue
}
r.Header.Set(strings.TrimSpace(elems[0]), strings.TrimSpace(elems[1]))
}
h.ServeHTTP(w, r)
}
return http.HandlerFunc(fn)
}
}