Capture proxy middleware error

Signed-off-by: Vishal Rana <[email protected]>

Author: vishr

middleware/proxy.go

@@ -92,24 +92,22 @@ func proxyRaw(t *ProxyTarget, c echo.Context) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		in, _, err := c.Response().Hijack()
 		if err != nil {
-			c.Error(fmt.Errorf("proxy raw, hijack error=%v, url=%s", t.URL, err))
+			c.Set("_error", fmt.Sprintf("proxy raw, hijack error=%v, url=%s", t.URL, err))
 			return
 		}
 		defer in.Close()
 
 		out, err := net.Dial("tcp", t.URL.Host)
 		if err != nil {
-			he := echo.NewHTTPError(http.StatusBadGateway, fmt.Sprintf("proxy raw, dial error=%v, url=%s", t.URL, err))
-			c.Error(he)
+			c.Set("_error", echo.NewHTTPError(http.StatusBadGateway, fmt.Sprintf("proxy raw, dial error=%v, url=%s", t.URL, err)))
 			return
 		}
 		defer out.Close()
 
 		// Write header
 		err = r.Write(out)
 		if err != nil {
-			he := echo.NewHTTPError(http.StatusBadGateway, fmt.Sprintf("proxy raw, request header copy error=%v, url=%s", t.URL, err))
-			c.Error(he)
+			c.Set("_error", echo.NewHTTPError(http.StatusBadGateway, fmt.Sprintf("proxy raw, request header copy error=%v, url=%s", t.URL, err)))
 			return
 		}
 
@@ -123,7 +121,7 @@ func proxyRaw(t *ProxyTarget, c echo.Context) http.Handler {
 		go cp(in, out)
 		err = <-errCh
 		if err != nil && err != io.EOF {
-			c.Logger().Errorf("proxy raw, copy body error=%v, url=%s", t.URL, err)
+			c.Set("_error", fmt.Errorf("proxy raw, copy body error=%v, url=%s", t.URL, err))
 		}
 	})
 }
@@ -251,6 +249,9 @@ func ProxyWithConfig(config ProxyConfig) echo.MiddlewareFunc {
 			default:
 				proxyHTTP(tgt, c, config).ServeHTTP(res, req)
 			}
+			if e, ok := c.Get("_error").(error); ok {
+				err = e
+			}
 
 			return
 		}

middleware/proxy_1_11.go

@@ -17,8 +17,7 @@ func proxyHTTP(tgt *ProxyTarget, c echo.Context, config ProxyConfig) http.Handle
 		if tgt.Name != "" {
 			desc = fmt.Sprintf("%s(%s)", tgt.Name, tgt.URL.String())
 		}
-		c.Logger().Errorf("remote %s unreachable, could not forward: %v", desc, err)
-		c.Error(echo.NewHTTPError(http.StatusServiceUnavailable))
+		c.Set("_error", echo.NewHTTPError(http.StatusBadGateway, fmt.Sprintf("remote %s unreachable, could not forward: %v", desc, err)))
 	}
 	proxy.Transport = config.Transport
 	return proxy