feat(chromium): add validation of 'emulatedMediaType' form field at the handler level

pkg/modules/chromium/routes.go

@@ -62,7 +62,21 @@ func FormDataChromiumPDFOptions(ctx *api.Context) (*api.FormData, Options) {
 
 			return nil
 		}).
-		String("emulatedMediaType", &emulatedMediaType, defaultOptions.EmulatedMediaType).
+		Custom("emulatedMediaType", func(value string) error {
+			if value == "" {
+				emulatedMediaType = defaultOptions.EmulatedMediaType
+
+				return nil
+			}
+
+			if value != "screen" && value != "print" {
+				return fmt.Errorf("wrong value, expected either 'screen', 'print' or empty")
+			}
+
+			emulatedMediaType = value
+
+			return nil
+		}).
 		Bool("landscape", &landscape, defaultOptions.Landscape).
 		Bool("printBackground", &printBackground, defaultOptions.PrintBackground).
 		Float64("scale", &scale, defaultOptions.Scale).
@@ -493,16 +507,6 @@ func convertURL(ctx *api.Context, chromium API, engine gotenberg.PDFEngine, URL,
 			)
 		}
 
-		if errors.Is(err, ErrInvalidEmulatedMediaType) {
-			return api.WrapError(
-				fmt.Errorf("convert to PDF: %w", err),
-				api.NewSentinelHTTPError(
-					http.StatusBadRequest,
-					fmt.Sprintf("The media type '%s' (emulatedMediaType) is invalid: allowed values are 'screen' or 'print'", options.EmulatedMediaType),
-				),
-			)
-		}
-
 		if errors.Is(err, ErrInvalidEvaluationExpression) {
 			if options.WaitForExpression == "" {
 				// We do not expect the 'waitWindowStatus' form field to return

pkg/modules/chromium/routes_test.go

@@ -54,6 +54,50 @@ func TestFormDataChromiumPDFOptions(t *testing.T) {
 					"foo": "bar",
 				}
 
+				return options
+			}(),
+		},
+		{
+			ctx: func() *api.MockContext {
+				ctx := &api.MockContext{Context: &api.Context{}}
+				ctx.SetValues(map[string][]string{
+					"extraHttpHeaders": {
+						"foo",
+					},
+				})
+
+				return ctx
+			}(),
+			options: DefaultOptions(),
+		},
+		{
+			ctx: func() *api.MockContext {
+				ctx := &api.MockContext{Context: &api.Context{}}
+				ctx.SetValues(map[string][]string{
+					"emulatedMediaType": {
+						"foo",
+					},
+				})
+
+				return ctx
+			}(),
+			options: DefaultOptions(),
+		},
+		{
+			ctx: func() *api.MockContext {
+				ctx := &api.MockContext{Context: &api.Context{}}
+				ctx.SetValues(map[string][]string{
+					"emulatedMediaType": {
+						"screen",
+					},
+				})
+
+				return ctx
+			}(),
+			options: func() Options {
+				options := DefaultOptions()
+				options.EmulatedMediaType = "screen"
+
 				return options
 			}(),
 		},
@@ -765,21 +809,6 @@ func TestConvertURL(t *testing.T) {
 			expectHTTPErr:    true,
 			expectHTTPStatus: http.StatusForbidden,
 		},
-		{
-			ctx: &api.MockContext{Context: &api.Context{}},
-			api: func() API {
-				chromiumAPI := struct{ ProtoAPI }{}
-				chromiumAPI.pdf = func(_ context.Context, _ *zap.Logger, _, _ string, _ Options) error {
-					return ErrInvalidEmulatedMediaType
-				}
-
-				return chromiumAPI
-			}(),
-			options:          DefaultOptions(),
-			expectErr:        true,
-			expectHTTPErr:    true,
-			expectHTTPStatus: http.StatusBadRequest,
-		},
 		{
 			ctx: &api.MockContext{Context: &api.Context{}},
 			api: func() API {