diff options
Diffstat (limited to 'modules/caddyhttp/reverseproxy/reverseproxy.go')
| -rw-r--r-- | modules/caddyhttp/reverseproxy/reverseproxy.go | 87 |
1 files changed, 82 insertions, 5 deletions
diff --git a/modules/caddyhttp/reverseproxy/reverseproxy.go b/modules/caddyhttp/reverseproxy/reverseproxy.go index 3355f0b..2131a91 100644 --- a/modules/caddyhttp/reverseproxy/reverseproxy.go +++ b/modules/caddyhttp/reverseproxy/reverseproxy.go @@ -790,12 +790,33 @@ func (h *Handler) reverseProxy(rw http.ResponseWriter, req *http.Request, repl * h.logger.Debug("handling response", zap.Int("handler", i)) + // we make some data available via request context to child routes + // so that they may inherit some options and functions from the + // handler, and be able to copy the response. + hrc := &handleResponseContext{ + handler: h, + response: res, + start: start, + logger: logger, + } + ctx := req.Context() + ctx = context.WithValue(ctx, proxyHandleResponseContextCtxKey, hrc) + // pass the request through the response handler routes - routeErr := rh.Routes.Compile(next).ServeHTTP(rw, req) + routeErr := rh.Routes.Compile(next).ServeHTTP(rw, req.WithContext(ctx)) + + // if the response handler routes already finalized the response, + // we can return early. It should be finalized if the routes executed + // included a copy_response handler. If a fresh response was written + // by the routes instead, then we still need to finalize the response + // without copying the body. + if routeErr == nil && hrc.isFinalized { + return nil + } - // always close the response body afterwards since it's expected + // always close the response body afterwards, since it's expected // that the response handler routes will have written to the - // response writer with a new body + // response writer with a new body, if it wasn't already finalized. res.Body.Close() bodyClosed = true @@ -804,8 +825,25 @@ func (h *Handler) reverseProxy(rw http.ResponseWriter, req *http.Request, repl * // the roundtrip was successful and to not retry return roundtripSucceeded{routeErr} } + + // we've already closed the body, so there's no use allowing + // another response handler to run as well + break } + return h.finalizeResponse(rw, req, res, repl, start, logger, bodyClosed) +} + +// finalizeResponse prepares and copies the response. +func (h Handler) finalizeResponse( + rw http.ResponseWriter, + req *http.Request, + res *http.Response, + repl *caddy.Replacer, + start time.Time, + logger *zap.Logger, + bodyClosed bool, +) error { // deal with 101 Switching Protocols responses: (WebSocket, h2c, etc) if res.StatusCode == http.StatusSwitchingProtocols { h.handleUpgradeResponse(logger, rw, req, res) @@ -818,6 +856,13 @@ func (h *Handler) reverseProxy(rw http.ResponseWriter, req *http.Request, repl * res.Header.Del(h) } + // remove the content length if we're not going to be copying + // from the response, because otherwise there'll be a mismatch + // between bytes written and the advertised length + if bodyClosed { + res.Header.Del("Content-Length") + } + // apply any response header operations if h.Headers != nil && h.Headers.Response != nil { if h.Headers.Response.Require == nil || @@ -841,7 +886,7 @@ func (h *Handler) reverseProxy(rw http.ResponseWriter, req *http.Request, repl * rw.WriteHeader(res.StatusCode) if !bodyClosed { - err = h.copyResponse(rw, res.Body, h.flushInterval(req, res)) + err := h.copyResponse(rw, res.Body, h.flushInterval(req, res)) res.Body.Close() // close now, instead of defer, to populate res.Trailer if err != nil { // we're streaming the response and we've already written headers, so @@ -863,7 +908,7 @@ func (h *Handler) reverseProxy(rw http.ResponseWriter, req *http.Request, repl * } // total duration spent proxying, including writing response body - repl.Set("http.reverse_proxy.upstream.duration", duration) + repl.Set("http.reverse_proxy.upstream.duration", time.Since(start)) if len(res.Trailer) == announcedTrailers { copyHeader(rw.Header(), res.Trailer) @@ -1227,6 +1272,38 @@ var bufPool = sync.Pool{ }, } +// handleResponseContext carries some contextual information about the +// the current proxy handling. +type handleResponseContext struct { + // handler is the active proxy handler instance, so that + // routes like copy_response may inherit some config + // options and have access to handler methods. + handler *Handler + + // response is the actual response received from the proxy + // roundtrip, to potentially be copied if a copy_response + // handler is in the handle_response routes. + response *http.Response + + // start is the time just before the proxy roundtrip was + // performed, used for logging. + start time.Time + + // logger is the prepared logger which is used to write logs + // with the request, duration, and selected upstream attached. + logger *zap.Logger + + // isFinalized is whether the response has been finalized, + // i.e. copied and closed, to make sure that it doesn't + // happen twice. + isFinalized bool +} + +// proxyHandleResponseContextCtxKey is the context key for the active proxy handler +// so that handle_response routes can inherit some config options +// from the proxy handler. +const proxyHandleResponseContextCtxKey caddy.CtxKey = "reverse_proxy_handle_response_context" + // Interface guards var ( _ caddy.Provisioner = (*Handler)(nil) |