mirror of
https://github.com/traefik/traefik.git
synced 2025-10-31 08:21:27 +01:00
141 lines
3.5 KiB
Go
141 lines
3.5 KiB
Go
package recovery
|
|
|
|
import (
|
|
"bufio"
|
|
"context"
|
|
"fmt"
|
|
"net"
|
|
"net/http"
|
|
"runtime"
|
|
|
|
"github.com/traefik/traefik/v3/pkg/middlewares"
|
|
)
|
|
|
|
const (
|
|
typeName = "Recovery"
|
|
middlewareName = "traefik-internal-recovery"
|
|
)
|
|
|
|
type recovery struct {
|
|
next http.Handler
|
|
}
|
|
|
|
// New creates recovery middleware.
|
|
func New(ctx context.Context, next http.Handler) (http.Handler, error) {
|
|
middlewares.GetLogger(ctx, middlewareName, typeName).Debug().Msg("Creating middleware")
|
|
|
|
return &recovery{
|
|
next: next,
|
|
}, nil
|
|
}
|
|
|
|
func (re *recovery) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
|
|
recoveryRW := newRecoveryResponseWriter(rw)
|
|
defer recoverFunc(recoveryRW, req)
|
|
|
|
re.next.ServeHTTP(recoveryRW, req)
|
|
}
|
|
|
|
func recoverFunc(rw recoveryResponseWriter, req *http.Request) {
|
|
if err := recover(); err != nil {
|
|
defer rw.finalizeResponse()
|
|
|
|
logger := middlewares.GetLogger(req.Context(), middlewareName, typeName)
|
|
if !shouldLogPanic(err) {
|
|
logger.Debug().Msgf("Request has been aborted [%s - %s]: %v", req.RemoteAddr, req.URL, err)
|
|
return
|
|
}
|
|
|
|
logger.Error().Msgf("Recovered from panic in HTTP handler [%s - %s]: %+v", req.RemoteAddr, req.URL, err)
|
|
const size = 64 << 10
|
|
buf := make([]byte, size)
|
|
buf = buf[:runtime.Stack(buf, false)]
|
|
logger.Error().Msgf("Stack: %s", buf)
|
|
}
|
|
}
|
|
|
|
// https://github.com/golang/go/blob/a0d6420d8be2ae7164797051ec74fa2a2df466a1/src/net/http/server.go#L1761-L1775
|
|
// https://github.com/golang/go/blob/c33153f7b416c03983324b3e8f869ce1116d84bc/src/net/http/httputil/reverseproxy.go#L284
|
|
func shouldLogPanic(panicValue interface{}) bool {
|
|
//nolint:errorlint // false-positive because panicValue is an interface.
|
|
return panicValue != nil && panicValue != http.ErrAbortHandler
|
|
}
|
|
|
|
type recoveryResponseWriter interface {
|
|
http.ResponseWriter
|
|
|
|
finalizeResponse()
|
|
}
|
|
|
|
func newRecoveryResponseWriter(rw http.ResponseWriter) recoveryResponseWriter {
|
|
wrapper := &responseWriterWrapper{rw: rw}
|
|
if _, ok := rw.(http.CloseNotifier); !ok {
|
|
return wrapper
|
|
}
|
|
|
|
return &responseWriterWrapperWithCloseNotify{wrapper}
|
|
}
|
|
|
|
type responseWriterWrapper struct {
|
|
rw http.ResponseWriter
|
|
headersSent bool
|
|
}
|
|
|
|
func (r *responseWriterWrapper) Header() http.Header {
|
|
return r.rw.Header()
|
|
}
|
|
|
|
func (r *responseWriterWrapper) Write(bytes []byte) (int, error) {
|
|
r.headersSent = true
|
|
return r.rw.Write(bytes)
|
|
}
|
|
|
|
func (r *responseWriterWrapper) WriteHeader(code int) {
|
|
if r.headersSent {
|
|
return
|
|
}
|
|
|
|
// Handling informational headers.
|
|
if code >= 100 && code <= 199 {
|
|
r.rw.WriteHeader(code)
|
|
return
|
|
}
|
|
|
|
r.headersSent = true
|
|
r.rw.WriteHeader(code)
|
|
}
|
|
|
|
func (r *responseWriterWrapper) Flush() {
|
|
if f, ok := r.rw.(http.Flusher); ok {
|
|
f.Flush()
|
|
}
|
|
}
|
|
|
|
func (r *responseWriterWrapper) Hijack() (net.Conn, *bufio.ReadWriter, error) {
|
|
if h, ok := r.rw.(http.Hijacker); ok {
|
|
return h.Hijack()
|
|
}
|
|
|
|
return nil, nil, fmt.Errorf("not a hijacker: %T", r.rw)
|
|
}
|
|
|
|
func (r *responseWriterWrapper) finalizeResponse() {
|
|
// If headers have been sent this is not possible to respond with an HTTP error,
|
|
// and we let the server abort the response silently thanks to the http.ErrAbortHandler sentinel panic value.
|
|
if r.headersSent {
|
|
panic(http.ErrAbortHandler)
|
|
}
|
|
|
|
// The response has not yet started to be written,
|
|
// we can safely return a fresh new error response.
|
|
http.Error(r.rw, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
|
|
}
|
|
|
|
type responseWriterWrapperWithCloseNotify struct {
|
|
*responseWriterWrapper
|
|
}
|
|
|
|
func (r *responseWriterWrapperWithCloseNotify) CloseNotify() <-chan bool {
|
|
return r.rw.(http.CloseNotifier).CloseNotify()
|
|
}
|