diff options
Diffstat (limited to 'vendor/github.com/labstack/echo/v4/middleware/proxy_1_11.go')
| -rw-r--r-- | vendor/github.com/labstack/echo/v4/middleware/proxy_1_11.go | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/vendor/github.com/labstack/echo/v4/middleware/proxy_1_11.go b/vendor/github.com/labstack/echo/v4/middleware/proxy_1_11.go index a4392781..17d142d8 100644 --- a/vendor/github.com/labstack/echo/v4/middleware/proxy_1_11.go +++ b/vendor/github.com/labstack/echo/v4/middleware/proxy_1_11.go @@ -3,13 +3,22 @@ package middleware import ( + "context" "fmt" "net/http" "net/http/httputil" + "strings" "github.com/labstack/echo/v4" ) +// StatusCodeContextCanceled is a custom HTTP status code for situations +// where a client unexpectedly closed the connection to the server. +// As there is no standard error code for "client closed connection", but +// various well-known HTTP clients and server implement this HTTP code we use +// 499 too instead of the more problematic 5xx, which does not allow to detect this situation +const StatusCodeContextCanceled = 499 + func proxyHTTP(tgt *ProxyTarget, c echo.Context, config ProxyConfig) http.Handler { proxy := httputil.NewSingleHostReverseProxy(tgt.URL) proxy.ErrorHandler = func(resp http.ResponseWriter, req *http.Request, err error) { @@ -17,7 +26,20 @@ 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.Set("_error", echo.NewHTTPError(http.StatusBadGateway, fmt.Sprintf("remote %s unreachable, could not forward: %v", desc, err))) + // If the client canceled the request (usually by closing the connection), we can report a + // client error (4xx) instead of a server error (5xx) to correctly identify the situation. + // The Go standard library (at of late 2020) wraps the exported, standard + // context.Canceled error with unexported garbage value requiring a substring check, see + // https://github.com/golang/go/blob/6965b01ea248cabb70c3749fd218b36089a21efb/src/net/net.go#L416-L430 + if err == context.Canceled || strings.Contains(err.Error(), "operation was canceled") { + httpError := echo.NewHTTPError(StatusCodeContextCanceled, fmt.Sprintf("client closed connection: %v", err)) + httpError.Internal = err + c.Set("_error", httpError) + } else { + httpError := echo.NewHTTPError(http.StatusBadGateway, fmt.Sprintf("remote %s unreachable, could not forward: %v", desc, err)) + httpError.Internal = err + c.Set("_error", httpError) + } } proxy.Transport = config.Transport proxy.ModifyResponse = config.ModifyResponse |