feat(chromium): add user agent override

pkg/modules/chromium/browser.go

@@ -227,6 +227,7 @@ func (b *chromiumBrowser) pdf(ctx context.Context, logger *zap.Logger, url, outp
 		clearCookiesActionFunc(logger, b.arguments.clearCookies),
 		disableJavaScriptActionFunc(logger, b.arguments.disableJavaScript),
 		setCookiesActionFunc(logger, options.Cookies),
+		userAgentOverride(logger, options.UserAgent),
 		extraHttpHeadersActionFunc(logger, options.ExtraHttpHeaders),
 		navigateActionFunc(logger, url, options.SkipNetworkIdleEvent),
 		hideDefaultWhiteBackgroundActionFunc(logger, options.OmitBackground, options.PrintBackground),
@@ -250,6 +251,7 @@ func (b *chromiumBrowser) screenshot(ctx context.Context, logger *zap.Logger, ur
 		clearCookiesActionFunc(logger, b.arguments.clearCookies),
 		disableJavaScriptActionFunc(logger, b.arguments.disableJavaScript),
 		setCookiesActionFunc(logger, options.Cookies),
+		userAgentOverride(logger, options.UserAgent),
 		extraHttpHeadersActionFunc(logger, options.ExtraHttpHeaders),
 		navigateActionFunc(logger, url, options.SkipNetworkIdleEvent),
 		hideDefaultWhiteBackgroundActionFunc(logger, options.OmitBackground, true),

pkg/modules/chromium/browser_test.go

@@ -614,6 +614,41 @@ func TestChromiumBrowser_pdf(t *testing.T) {
 				"set cookie",
 			},
 		},
+		{
+			scenario: "user agent override",
+			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))
+				}
+
+				err = os.WriteFile(fmt.Sprintf("%s/index.html", fs.WorkingDirPath()), []byte("<h1>User-Agent override</h1>"), 0o755)
+				if err != nil {
+					t.Fatalf("expected no error but got: %v", err)
+				}
+
+				return fs
+			}(),
+			options: PdfOptions{
+				Options: Options{UserAgent: "foo"},
+			},
+			noDeadline:  false,
+			start:       true,
+			expectError: false,
+			expectedLogEntries: []string{
+				fmt.Sprintf("user agent override: foo"),
+			},
+		},
 		{
 			scenario: "extra HTTP headers",
 			browser: newChromiumBrowser(
@@ -1990,6 +2025,7 @@ func TestChromiumBrowser_screenshot(t *testing.T) {
 				"cache not cleared",
 				"cookies not cleared",
 				"JavaScript not disabled",
+				"no user agent override",
 				"no extra HTTP headers",
 				"navigate to",
 				"default white background not hidden",
@@ -2037,6 +2073,7 @@ func TestChromiumBrowser_screenshot(t *testing.T) {
 				"cookies not cleared",
 				"JavaScript not disabled",
 				"no cookies to set",
+				"no user agent override",
 				"no extra HTTP headers",
 				"navigate to",
 				"default white background not hidden",
@@ -2084,6 +2121,7 @@ func TestChromiumBrowser_screenshot(t *testing.T) {
 				"cookies not cleared",
 				"JavaScript not disabled",
 				"no cookies to set",
+				"no user agent override",
 				"no extra HTTP headers",
 				"navigate to",
 				"default white background not hidden",

pkg/modules/chromium/chromium.go

@@ -108,8 +108,12 @@ type Options struct {
 	// Optional
 	Cookies []Cookie
 
-	// ExtraHttpHeaders are the HTTP headers to send by Chromium while loading
+	// UserAgent overrides the default 'User-Agent' HTTP header.
-	// the HTML document.
+	// Optional.
+	UserAgent string
+
+	// ExtraHttpHeaders are extra HTTP headers to send by Chromium while
+	// loading he HTML document.
 	// Optional.
 	ExtraHttpHeaders map[string]string
 
@@ -134,6 +138,7 @@ func DefaultOptions() Options {
 		WaitWindowStatus:        "",
 		WaitForExpression:       "",
 		Cookies:                 nil,
+		UserAgent:               "",
 		ExtraHttpHeaders:        nil,
 		EmulatedMediaType:       "",
 		OmitBackground:          false,

pkg/modules/chromium/routes.go

@@ -35,6 +35,7 @@ func FormDataChromiumOptions(ctx *api.Context) (*api.FormData, Options) {
 		waitWindowStatus        string
 		waitForExpression       string
 		cookies                 []Cookie
+		userAgent               string
 		extraHttpHeaders        map[string]string
 		emulatedMediaType       string
 		omitBackground          bool
@@ -78,6 +79,7 @@ func FormDataChromiumOptions(ctx *api.Context) (*api.FormData, Options) {
 
 			return err
 		}).
+		String("userAgent", &userAgent, defaultOptions.UserAgent).
 		Custom("extraHttpHeaders", func(value string) error {
 			if value == "" {
 				extraHttpHeaders = defaultOptions.ExtraHttpHeaders
@@ -115,6 +117,7 @@ func FormDataChromiumOptions(ctx *api.Context) (*api.FormData, Options) {
 		WaitWindowStatus:        waitWindowStatus,
 		WaitForExpression:       waitForExpression,
 		Cookies:                 cookies,
+		UserAgent:               userAgent,
 		ExtraHttpHeaders:        extraHttpHeaders,
 		EmulatedMediaType:       emulatedMediaType,
 		OmitBackground:          omitBackground,

pkg/modules/chromium/tasks.go

@@ -281,6 +281,23 @@ func setCookiesActionFunc(logger *zap.Logger, cookies []Cookie) chromedp.ActionF
 	}
 }
 
+func userAgentOverride(logger *zap.Logger, userAgent string) chromedp.ActionFunc {
+	return func(ctx context.Context) error {
+		if len(userAgent) == 0 {
+			logger.Debug("no user agent override")
+			return nil
+		}
+
+		logger.Debug(fmt.Sprintf("user agent override: %s", userAgent))
+		err := emulation.SetUserAgentOverride(userAgent).Do(ctx)
+		if err == nil {
+			return nil
+		}
+
+		return fmt.Errorf("set user agent override: %w", err)
+	}
+}
+
 func extraHttpHeadersActionFunc(logger *zap.Logger, extraHttpHeaders map[string]string) chromedp.ActionFunc {
 	return func(ctx context.Context) error {
 		if len(extraHttpHeaders) == 0 {