feat: passthrough proxies

internal/proxy/director/context.go

@@ -34,19 +34,6 @@ func OriginalURL(ctx context.Context) (*url.URL, error) {
 	return url, nil
 }
 
-func withProxy(ctx context.Context, proxy *store.Proxy) context.Context {
-	return context.WithValue(ctx, contextKeyProxy, proxy)
-}
-
-func ctxProxy(ctx context.Context) (*store.Proxy, error) {
-	proxy, err := ctxValue[*store.Proxy](ctx, contextKeyProxy)
-	if err != nil {
-		return nil, errors.WithStack(err)
-	}
-
-	return proxy, nil
-}
-
 func withLayers(ctx context.Context, layers []*store.Layer) context.Context {
 	return context.WithValue(ctx, contextKeyLayers, layers)
 }

internal/proxy/director/director.go

@@ -36,15 +36,15 @@ func (d *Director) rewriteRequest(r *http.Request) (*http.Request, error) {
 	ctx = withOriginalURL(ctx, url)
 	ctx = logger.With(ctx, logger.F("url", url.String()))
 
-	var match *store.Proxy
+	layers := make([]*store.Layer, 0)
 
-MAIN:
 	for _, p := range proxies {
 		for _, from := range p.From {
 			logger.Debug(
 				ctx, "matching request with proxy's from",
 				logger.F("from", from),
 			)
+
 			if matches := wildcard.Match(url.String(), from); !matches {
 				continue
 			}
@@ -54,44 +54,41 @@ MAIN:
 				logger.F("from", from),
 			)
 
-			match = p
-			break MAIN
+			ctx = logger.With(ctx,
+				logger.F("proxy", p.Name),
+				logger.F("host", r.Host),
+				logger.F("remoteAddr", r.RemoteAddr),
+			)
+
+			metricProxyRequestsTotal.With(prometheus.Labels{metricLabelProxy: string(p.Name)}).Add(1)
+
+			proxyLayers, err := d.getLayers(ctx, p.Name)
+			if err != nil {
+				return r, errors.WithStack(err)
+			}
+
+			layers = append(layers, proxyLayers...)
+
+			if p.To == "" {
+				continue
+			}
+
+			toURL, err := url.Parse(p.To)
+			if err != nil {
+				return r, errors.WithStack(err)
+			}
+
+			r.URL.Host = toURL.Host
+			r.URL.Scheme = toURL.Scheme
+			r.URL.Path = toURL.JoinPath(r.URL.Path).Path
+
+			ctx = withLayers(ctx, layers)
+			r = r.WithContext(ctx)
+
+			return r, nil
 		}
 	}
 
-	if match == nil {
-		return r, nil
-	}
-
-	toURL, err := url.Parse(match.To)
-	if err != nil {
-		return r, errors.WithStack(err)
-	}
-
-	r.URL.Host = toURL.Host
-	r.URL.Scheme = toURL.Scheme
-	r.URL.Path = toURL.JoinPath(r.URL.Path).Path
-
-	ctx = logger.With(ctx,
-		logger.F("proxy", match.Name),
-		logger.F("host", r.Host),
-		logger.F("remoteAddr", r.RemoteAddr),
-	)
-
-	logger.Debug(
-		ctx, "rewritten url",
-		logger.F("rewrittenURL", r.URL.String()),
-	)
-
-	metricProxyRequestsTotal.With(prometheus.Labels{metricLabelProxy: string(match.Name)}).Add(1)
-
-	ctx = withProxy(ctx, match)
-
-	layers, err := d.getLayers(ctx, match.Name)
-	if err != nil {
-		return r, errors.WithStack(err)
-	}
-
 	ctx = withLayers(ctx, layers)
 	r = r.WithContext(ctx)
 

internal/proxy/server.go

@@ -157,6 +157,7 @@ func (s *Server) run(parentCtx context.Context, addrs chan net.Addr, errs chan e
 				director.ResponseTransformer(),
 			),
 			proxy.WithReverseProxyFactory(s.createReverseProxy),
+			proxy.WithDefaultHandler(http.HandlerFunc(s.handleDefault)),
 		)
 
 		r.Handle("/*", handler)
@@ -185,12 +186,21 @@ func (s *Server) createReverseProxy(ctx context.Context, target *url.URL) *httpu
 	httpTransport.DialContext = dialer.DialContext
 
 	reverseProxy.Transport = httpTransport
-	reverseProxy.ErrorHandler = s.errorHandler
+	reverseProxy.ErrorHandler = s.handleError
 
 	return reverseProxy
 }
 
-func (s *Server) errorHandler(w http.ResponseWriter, r *http.Request, err error) {
+func (s *Server) handleDefault(w http.ResponseWriter, r *http.Request) {
+	err := errors.Errorf("no proxy target found")
+
+	logger.Error(r.Context(), "proxy error", logger.E(err))
+	sentry.CaptureException(err)
+
+	s.renderErrorPage(w, r, err, http.StatusBadGateway, http.StatusText(http.StatusBadGateway))
+}
+
+func (s *Server) handleError(w http.ResponseWriter, r *http.Request, err error) {
 	err = errors.WithStack(err)
 
 	logger.Error(r.Context(), "proxy error", logger.E(err))