feat(chromium): add 'extraLinkTags' and 'extraScriptTags' form fields, add auto-detection of files for URL endpoint, disable some functionalities if JavaScript is disabled

pkg/modules/chromium/routes.go

@@ -84,7 +84,9 @@ func FormDataChromiumPDFOptions(ctx *api.Context) (*api.FormData, Options) {
 		WaitForExpression:       waitForExpression,
 		UserAgent:               userAgent,
 		ExtraHTTPHeaders:        extraHTTPHeaders,
+		ExtraLinkTags:           defaultOptions.ExtraLinkTags,
 		EmulatedMediaType:       emulatedMediaType,
+		ExtraScriptTags:         defaultOptions.ExtraScriptTags,
 		Landscape:               landscape,
 		PrintBackground:         printBackground,
 		Scale:                   scale,
@@ -114,19 +116,209 @@ func convertURLRoute(chromium API, engine gotenberg.PDFEngine) api.Route {
 			form, options := FormDataChromiumPDFOptions(ctx)
 
 			var (
-				URL       string
-				PDFformat string
+				URL         string
+				PDFformat   string
+				linkPaths   []string
+				scriptPaths []string
 			)
 
 			err := form.
 				MandatoryString("url", &URL).
 				String("pdfFormat", &PDFformat, "").
+				Custom("extraLinkTags", func(value string) error {
+					if value == "" {
+						return nil
+					}
+
+					err := json.Unmarshal([]byte(value), &options.ExtraLinkTags)
+					if err != nil {
+						return fmt.Errorf("unmarshal extra link tags: %w", err)
+					}
+
+					return nil
+				}).
+				Custom("extraScriptTags", func(value string) error {
+					if value == "" {
+						return nil
+					}
+
+					err := json.Unmarshal([]byte(value), &options.ExtraScriptTags)
+					if err != nil {
+						return fmt.Errorf("unmarshal extra script tags: %w", err)
+					}
+
+					return nil
+				}).
+				Paths([]string{".woff2", ".woff", ".ttf", ".css"}, &linkPaths).
+				Paths([]string{".js"}, &scriptPaths).
 				Validate()
 
 			if err != nil {
 				return fmt.Errorf("validate form data: %w", err)
 			}
 
+			// Thanks to Options.LinkTags and Options.ScriptTags, one may
+			// "hijack" the content of a remote HTML document (for instance, a
+			// website) by loading external assets like scripts or CSS
+			// stylesheets.
+			//
+			// There are two possibilities:
+			//
+			// 1. We auto-detect all files sent in the request that match the
+			// following file extensions: ".woff2", ".woff", ".ttf", ".css",
+			// ".css", and ".js".
+			//
+			// 2. The user has sent both files and a JSON mapping via the
+			// "extraLinkTags" and/or "extraScriptTags" form fields. In such a
+			// scenario, the JSON mapping has the priority for ordering, and
+			// files which are a not mapped are added at the end. The user may
+			// also have sent remote URLs in the JSON mapping.
+
+			// First, let's handle the HTML <link> elements.
+			hasExtraLinkTags := len(options.ExtraLinkTags) > 0
+			hasLinkPaths := len(linkPaths) > 0
+
+			if !hasExtraLinkTags && hasLinkPaths {
+				// First scenario: there is no JSON mapping, we simply add the
+				// paths.
+				options.ExtraLinkTags = make([]LinkTag, len(linkPaths))
+
+				for i, path := range linkPaths {
+					options.ExtraLinkTags[i] = LinkTag{
+						Href: filepath.Base(path),
+					}
+				}
+			} else if hasExtraLinkTags && hasLinkPaths {
+				// Second scenario: there are both files and a JSON mapping.
+
+				// First, find the filenames of the files.
+				filenames := make([]string, len(linkPaths))
+				for i, path := range linkPaths {
+					filenames[i] = filepath.Base(path)
+				}
+
+				var extraLinkTags []LinkTag
+
+				// Then, let's find the filenames that exist in the JSON
+				// mapping, plus the entries that do only exist in the JSON
+				// mapping.
+				for _, linkTagFromMapping := range options.ExtraLinkTags {
+					found := false
+
+					for _, filename := range filenames {
+						if linkTagFromMapping.Href == filename {
+							extraLinkTags = append(extraLinkTags, linkTagFromMapping)
+							found = true
+
+							break
+						}
+					}
+
+					if !found {
+						// This entry only exist in the JSON mapping.
+						extraLinkTags = append(extraLinkTags, linkTagFromMapping)
+					}
+				}
+
+				// Then, add the remaining filenames.
+				for _, filename := range filenames {
+					found := false
+
+					for _, linkTag := range extraLinkTags {
+						if linkTag.Href == filename {
+							found = true
+
+							break
+						}
+					}
+
+					if !found {
+						extraLinkTags = append(extraLinkTags, LinkTag{
+							Href: filename,
+						})
+					}
+				}
+
+				// Last but not least, update the options.
+				options.ExtraLinkTags = extraLinkTags
+			}
+
+			// Next, let's handle the HTML <script> elements.
+			hasExtraScriptTags := len(options.ExtraScriptTags) > 0
+			hasScriptPaths := len(scriptPaths) > 0
+
+			if !hasExtraScriptTags && hasScriptPaths {
+				// First scenario: there is no JSON mapping, we simply add the
+				// paths.
+				options.ExtraScriptTags = make([]ScriptTag, len(scriptPaths))
+
+				for i, path := range scriptPaths {
+					options.ExtraScriptTags[i] = ScriptTag{
+						Src: filepath.Base(path),
+					}
+				}
+			} else if hasExtraScriptTags && hasScriptPaths {
+				// Second scenario: there are both files and a JSON mapping.
+
+				// First, find the filenames of the files.
+				filenames := make([]string, len(scriptPaths))
+				for i, path := range scriptPaths {
+					filenames[i] = filepath.Base(path)
+				}
+
+				var extraScriptTags []ScriptTag
+
+				// Then, let's find the filenames that exist in the JSON
+				// mapping, plus the entries that do only exist in the JSON
+				// mapping.
+				for _, scriptTagFromMapping := range options.ExtraScriptTags {
+					found := false
+
+					for _, filename := range filenames {
+						if scriptTagFromMapping.Src == filename {
+							extraScriptTags = append(extraScriptTags, scriptTagFromMapping)
+							found = true
+
+							break
+						}
+					}
+
+					if !found {
+						// This entry only exist in the JSON mapping.
+						extraScriptTags = append(extraScriptTags, scriptTagFromMapping)
+					}
+				}
+
+				// Then, add the remaining filenames.
+				for _, filename := range filenames {
+					found := false
+
+					for _, scriptTag := range extraScriptTags {
+						if scriptTag.Src == filename {
+							found = true
+
+							break
+						}
+					}
+
+					if !found {
+						extraScriptTags = append(extraScriptTags, ScriptTag{
+							Src: filename,
+						})
+					}
+				}
+
+				// Last but not least, update the options.
+				options.ExtraScriptTags = extraScriptTags
+			}
+
+			// For both <link> and <script> HTML elements, other scenarios are:
+			//
+			// 1. No files and no JSON mapping.
+			// 2. No files but JSON mapping.
+			//
+			// Nothing to do in such cases.
+
 			err = convertURL(ctx, chromium, engine, URL, PDFformat, options)
 			if err != nil {
 				return fmt.Errorf("convert URL to PDF: %w", err)