feat(chromium): HTTP Bad Request on net::ERR_CONNECTION_REFUSED

pkg/modules/chromium/browser.go

@@ -314,6 +314,14 @@ func (b *chromiumBrowser) do(ctx context.Context, logger *zap.Logger, url string
 		listenForEventExceptionThrown(taskCtx, logger, &consoleExceptions, &consoleExceptionsMu)
 	}
 
+	var (
+		connectionRefused   error
+		connectionRefusedMu sync.RWMutex
+	)
+
+	// See https://github.com/gotenberg/gotenberg/issues/913.
+	listenForEventLoadingFailedOnConnectionRefused(taskCtx, logger, &connectionRefused, &connectionRefusedMu)
+
 	err = chromedp.Run(taskCtx, tasks...)
 	if err != nil {
 		errMessage := err.Error()
@@ -349,6 +357,14 @@ func (b *chromiumBrowser) do(ctx context.Context, logger *zap.Logger, url string
 		return fmt.Errorf("%v: %w", consoleExceptions, ErrConsoleExceptions)
 	}
 
+	// See https://github.com/gotenberg/gotenberg/issues/913.
+	connectionRefusedMu.RLock()
+	defer connectionRefusedMu.RUnlock()
+
+	if connectionRefused != nil {
+		return fmt.Errorf("%v: %w", connectionRefused, ErrConnectionRefused)
+	}
+
 	return nil
 }
 

pkg/modules/chromium/browser_test.go

@@ -249,6 +249,7 @@ func TestChromiumBrowser_pdf(t *testing.T) {
 		browser            browser
 		fs                 *gotenberg.FileSystem
 		options            PdfOptions
+		url                string
 		noDeadline         bool
 		start              bool
 		expectError        bool
@@ -478,6 +479,32 @@ func TestChromiumBrowser_pdf(t *testing.T) {
 			expectError:   true,
 			expectedError: ErrConsoleExceptions,
 		},
+		{
+			scenario: "ErrConnectionRefused",
+			browser: newChromiumBrowser(
+				browserArguments{
+					binPath:          os.Getenv("CHROMIUM_BIN_PATH"),
+					wsUrlReadTimeout: 5 * time.Second,
+					allowList:        regexp2.MustCompile("", 0),
+					denyList:         regexp2.MustCompile("", 0),
+				},
+			),
+			fs: func() *gotenberg.FileSystem {
+				fs := gotenberg.NewFileSystem()
+
+				err := os.MkdirAll(fs.WorkingDirPath(), 0o755)
+				if err != nil {
+					t.Fatalf(fmt.Sprintf("expected no error but got: %v", err))
+				}
+
+				return fs
+			}(),
+			url:           "http://localhost:100",
+			noDeadline:    false,
+			start:         true,
+			expectError:   true,
+			expectedError: ErrConnectionRefused,
+		},
 		{
 			scenario: "clear cache",
 			browser: newChromiumBrowser(
@@ -1243,10 +1270,15 @@ func TestChromiumBrowser_pdf(t *testing.T) {
 				defer cancel()
 			}
 
+			url := fmt.Sprintf("file://%s/index.html", tc.fs.WorkingDirPath())
+			if tc.url != "" {
+				url = tc.url
+			}
+
 			err := tc.browser.pdf(
 				ctx,
 				logger,
-				fmt.Sprintf("file://%s/index.html", tc.fs.WorkingDirPath()),
+				url,
 				fmt.Sprintf("%s/%s.pdf", tc.fs.WorkingDirPath(), uuid.NewString()),
 				tc.options,
 			)
@@ -1286,6 +1318,7 @@ func TestChromiumBrowser_screenshot(t *testing.T) {
 		browser            browser
 		fs                 *gotenberg.FileSystem
 		options            ScreenshotOptions
+		url                string
 		noDeadline         bool
 		start              bool
 		expectError        bool
@@ -1519,6 +1552,33 @@ func TestChromiumBrowser_screenshot(t *testing.T) {
 			expectError:   true,
 			expectedError: ErrConsoleExceptions,
 		},
+		{
+			scenario: "ErrConnectionRefused",
+			browser: newChromiumBrowser(
+				browserArguments{
+					binPath:          os.Getenv("CHROMIUM_BIN_PATH"),
+					wsUrlReadTimeout: 5 * time.Second,
+					allowList:        regexp2.MustCompile("", 0),
+					denyList:         regexp2.MustCompile("", 0),
+				},
+			),
+
+			fs: func() *gotenberg.FileSystem {
+				fs := gotenberg.NewFileSystem()
+
+				err := os.MkdirAll(fs.WorkingDirPath(), 0o755)
+				if err != nil {
+					t.Fatalf(fmt.Sprintf("expected no error but got: %v", err))
+				}
+
+				return fs
+			}(),
+			url:           "http://localhost:100",
+			noDeadline:    false,
+			start:         true,
+			expectError:   true,
+			expectedError: ErrConnectionRefused,
+		},
 		{
 			scenario: "clear cache",
 			browser: newChromiumBrowser(
@@ -2169,10 +2229,15 @@ func TestChromiumBrowser_screenshot(t *testing.T) {
 				defer cancel()
 			}
 
+			url := fmt.Sprintf("file://%s/index.html", tc.fs.WorkingDirPath())
+			if tc.url != "" {
+				url = tc.url
+			}
+
 			err := tc.browser.screenshot(
 				ctx,
 				logger,
-				fmt.Sprintf("file://%s/index.html", tc.fs.WorkingDirPath()),
+				url,
 				fmt.Sprintf("%s/%s.pdf", tc.fs.WorkingDirPath(), uuid.NewString()),
 				tc.options,
 			)

pkg/modules/chromium/chromium.go

@@ -42,6 +42,9 @@ var (
 	// is set to true.
 	ErrConsoleExceptions = errors.New("console exceptions")
 
+	// ErrConnectionRefused happens when a URL cannot be reached.
+	ErrConnectionRefused = errors.New("connection refused")
+
 	// PDF specific.
 
 	// ErrOmitBackgroundWithoutPrintBackground happens if

pkg/modules/chromium/events.go

@@ -64,8 +64,8 @@ func listenForEventRequestPaused(ctx context.Context, logger *zap.Logger, allowL
 	})
 }
 
-// listenForEventResponseReceived listens for an invalid HTTP status code is
+// listenForEventResponseReceived listens for an invalid HTTP status code that
-// returned by the main page.
+// is returned by the main page.
 // See https://github.com/gotenberg/gotenberg/issues/613.
 func listenForEventResponseReceived(ctx context.Context, logger *zap.Logger, url string, failOnHttpStatusCodes []int64, invalidHttpStatusCode *error, invalidHttpStatusCodeMu *sync.RWMutex) {
 	for _, code := range []int64{199, 299, 399, 499, 599} {
@@ -95,6 +95,28 @@ func listenForEventResponseReceived(ctx context.Context, logger *zap.Logger, url
 	})
 }
 
+// listenForEventLoadingFailedOnConnectionRefused listens for an event
+// indicating that the main page failed to load.
+// See https://github.com/gotenberg/gotenberg/issues/913.
+func listenForEventLoadingFailedOnConnectionRefused(ctx context.Context, logger *zap.Logger, connectionRefused *error, connectionRefusedMu *sync.RWMutex) {
+	chromedp.ListenTarget(ctx, func(ev interface{}) {
+		switch ev := ev.(type) {
+		case *network.EventLoadingFailed:
+			logger.Debug(fmt.Sprintf("event EventLoadingFailed fired: %+v", ev.ErrorText))
+
+			if ev.ErrorText != "net::ERR_CONNECTION_REFUSED" || ev.Type != network.ResourceTypeDocument {
+				logger.Debug("skip EventLoadingFailed: is not net::ERR_CONNECTION_REFUSED and/or resource type Document")
+				return
+			}
+
+			connectionRefusedMu.Lock()
+			defer connectionRefusedMu.Unlock()
+
+			*connectionRefused = fmt.Errorf("%s", ev.ErrorText)
+		}
+	})
+}
+
 // listenForEventExceptionThrown listens for exceptions in the console and
 // appends those exceptions to the given error pointer.
 // See https://github.com/gotenberg/gotenberg/issues/262.

pkg/modules/chromium/routes.go

@@ -688,5 +688,15 @@ func handleChromiumError(err error, options Options) error {
 		)
 	}
 
+	if errors.Is(err, ErrConnectionRefused) {
+		return api.WrapError(
+			err,
+			api.NewSentinelHttpError(
+				http.StatusBadRequest,
+				"Chromium returned net::ERR_CONNECTION_REFUSED",
+			),
+		)
+	}
+
 	return err
 }

pkg/modules/chromium/routes_test.go

@@ -1435,6 +1435,18 @@ func TestConvertUrl(t *testing.T) {
 			expectHttpStatus:       http.StatusConflict,
 			expectOutputPathsCount: 0,
 		},
+		{
+			scenario: "ErrConnectionRefused",
+			ctx:      &api.ContextMock{Context: new(api.Context)},
+			api: &ApiMock{PdfMock: func(ctx context.Context, logger *zap.Logger, url, outputPath string, options PdfOptions) error {
+				return ErrConnectionRefused
+			}},
+			options:                DefaultPdfOptions(),
+			expectError:            true,
+			expectHttpError:        true,
+			expectHttpStatus:       http.StatusBadRequest,
+			expectOutputPathsCount: 0,
+		},
 		{
 			scenario: "error from Chromium",
 			ctx:      &api.ContextMock{Context: new(api.Context)},
@@ -1633,6 +1645,18 @@ func TestScreenshotUrl(t *testing.T) {
 			expectHttpStatus:       http.StatusConflict,
 			expectOutputPathsCount: 0,
 		},
+		{
+			scenario: "ErrConnectionRefused",
+			ctx:      &api.ContextMock{Context: new(api.Context)},
+			api: &ApiMock{ScreenshotMock: func(ctx context.Context, logger *zap.Logger, url, outputPath string, options ScreenshotOptions) error {
+				return ErrConnectionRefused
+			}},
+			options:                DefaultScreenshotOptions(),
+			expectError:            true,
+			expectHttpError:        true,
+			expectHttpStatus:       http.StatusBadRequest,
+			expectOutputPathsCount: 0,
+		},
 		{
 			scenario: "error from Chromium",
 			ctx:      &api.ContextMock{Context: new(api.Context)},