[api-minor] Support the Content-Disposition filename in the Firefox PDF Viewer (bug 1694556, PR 9379 follow-up)

As can be seen [in the mozilla-central code](https://searchfox.org/mozilla-central/rev/a6db3bd67367aa9ddd9505690cab09b47e65a762/toolkit/components/pdfjs/content/PdfStreamConverter.jsm#1222-1225), we're already getting the Content-Disposition filename. However, that data isn't passed through to the viewer nor to the `PDFDataTransportStream`-implementation, which explains why it's currently being ignored.

*Please note:* This will also require a small mozilla-central patch, see https://bugzilla.mozilla.org/show_bug.cgi?id=1694556, to forward the necessary data to the viewer.

src/display/api.js

@@ -334,6 +334,7 @@ function getDocument(src) {
               length: params.length,
               initialData: params.initialData,
               progressiveDone: params.progressiveDone,
+              contentDispositionFilename: params.contentDispositionFilename,
               disableRange: params.disableRange,
               disableStream: params.disableStream,
             },
@@ -401,6 +402,8 @@ function _fetchDocument(worker, source, pdfDataRangeTransport, docId) {
     source.length = pdfDataRangeTransport.length;
     source.initialData = pdfDataRangeTransport.initialData;
     source.progressiveDone = pdfDataRangeTransport.progressiveDone;
+    source.contentDispositionFilename =
+      pdfDataRangeTransport.contentDispositionFilename;
   }
   return worker.messageHandler
     .sendWithPromise("GetDocRequest", {
@@ -554,11 +557,18 @@ class PDFDataRangeTransport {
    * @param {number} length
    * @param {Uint8Array} initialData
    * @param {boolean} [progressiveDone]
+   * @param {string} [contentDispositionFilename]
    */
-  constructor(length, initialData, progressiveDone = false) {
+  constructor(
+    length,
+    initialData,
+    progressiveDone = false,
+    contentDispositionFilename = null
+  ) {
     this.length = length;
     this.initialData = initialData;
     this.progressiveDone = progressiveDone;
+    this.contentDispositionFilename = contentDispositionFilename;
 
     this._rangeListeners = [];
     this._progressListeners = [];

src/display/display_utils.js

@@ -451,6 +451,10 @@ function addLinkAttributes(link, { url, target, rel, enabled = true } = {}) {
   link.rel = typeof rel === "string" ? rel : DEFAULT_LINK_REL;
 }
 
+function isPdfFile(filename) {
+  return typeof filename === "string" && /\.pdf$/i.test(filename);
+}
+
 /**
  * Gets the file name from a given URL.
  * @param {string} url
@@ -652,6 +656,7 @@ export {
   DOMSVGFactory,
   getFilenameFromUrl,
   isFetchSupported,
+  isPdfFile,
   isValidFetchUrl,
   LinkTarget,
   loadScript,

src/display/network_utils.js

@@ -19,6 +19,7 @@ import {
   UnexpectedResponseException,
 } from "../shared/util.js";
 import { getFilenameFromContentDispositionHeader } from "./content_disposition.js";
+import { isPdfFile } from "./display_utils.js";
 
 function validateRangeRequestCapabilities({
   getResponseHeader,
@@ -70,7 +71,7 @@ function extractFilenameFromHeader(getResponseHeader) {
         filename = decodeURIComponent(filename);
       } catch (ex) {}
     }
-    if (/\.pdf$/i.test(filename)) {
+    if (isPdfFile(filename)) {
       return filename;
     }
   }
@@ -82,11 +83,7 @@ function createResponseStatusError(status, url) {
     return new MissingPDFException('Missing PDF "' + url + '".');
   }
   return new UnexpectedResponseException(
-    "Unexpected server response (" +
-      status +
-      ') while retrieving PDF "' +
-      url +
-      '".',
+    `Unexpected server response (${status}) while retrieving PDF "${url}".`,
     status
   );
 }

src/display/transport_stream.js

@@ -14,6 +14,7 @@
  */
 
 import { assert, createPromiseCapability } from "../shared/util.js";
+import { isPdfFile } from "./display_utils.js";
 
 /** @implements {IPDFStream} */
 class PDFDataTransportStream {
@@ -25,6 +26,8 @@ class PDFDataTransportStream {
 
     this._queuedChunks = [];
     this._progressiveDone = params.progressiveDone || false;
+    this._contentDispositionFilename =
+      params.contentDispositionFilename || null;
 
     const initialData = params.initialData;
     if (initialData?.length > 0) {
@@ -125,7 +128,8 @@ class PDFDataTransportStream {
     return new PDFDataTransportStreamReader(
       this,
       queuedChunks,
-      this._progressiveDone
+      this._progressiveDone,
+      this._contentDispositionFilename
     );
   }
 
@@ -153,10 +157,17 @@ class PDFDataTransportStream {
 
 /** @implements {IPDFStreamReader} */
 class PDFDataTransportStreamReader {
-  constructor(stream, queuedChunks, progressiveDone = false) {
+  constructor(
+    stream,
+    queuedChunks,
+    progressiveDone = false,
+    contentDispositionFilename = null
+  ) {
     this._stream = stream;
     this._done = progressiveDone || false;
-    this._filename = null;
+    this._filename = isPdfFile(contentDispositionFilename)
+      ? contentDispositionFilename
+      : null;
     this._queuedChunks = queuedChunks || [];
     this._loaded = 0;
     for (const chunk of this._queuedChunks) {

src/pdf.js

@@ -18,6 +18,7 @@ import {
   addLinkAttributes,
   getFilenameFromUrl,
   isFetchSupported,
+  isPdfFile,
   isValidFetchUrl,
   LinkTarget,
   loadScript,
@@ -128,6 +129,7 @@ export {
   // From "./display/display_utils.js":
   addLinkAttributes,
   getFilenameFromUrl,
+  isPdfFile,
   LinkTarget,
   loadScript,
   PDFDateString,

web/app.js

@@ -44,6 +44,7 @@ import {
   getFilenameFromUrl,
   GlobalWorkerOptions,
   InvalidPDFException,
+  isPdfFile,
   LinkTarget,
   loadScript,
   MissingPDFException,
@@ -727,7 +728,10 @@ const PDFViewerApplication = {
       onOpenWithTransport: (url, length, transport) => {
         this.open(url, { length, range: transport });
       },
-      onOpenWithData: data => {
+      onOpenWithData: (data, contentDispositionFilename) => {
+        if (isPdfFile(contentDispositionFilename)) {
+          this._contentDispositionFilename = contentDispositionFilename;
+        }
         this.open(data);
       },
       onOpenWithURL: (url, length, originalUrl) => {
@@ -1744,7 +1748,7 @@ const PDFViewerApplication = {
     }
     this.documentInfo = info;
     this.metadata = metadata;
-    this._contentDispositionFilename = contentDispositionFilename;
+    this._contentDispositionFilename ??= contentDispositionFilename;
     this._contentLength ??= contentLength; // See `getDownloadInfo`-call above.
 
     // Provides some basic debug information

web/download_manager.js

@@ -13,8 +13,7 @@
  * limitations under the License.
  */
 
-import { createObjectURL, createValidAbsoluteUrl } from "pdfjs-lib";
-import { PdfFileRegExp } from "./ui_utils.js";
+import { createObjectURL, createValidAbsoluteUrl, isPdfFile } from "pdfjs-lib";
 import { viewerCompatibilityParams } from "./viewer_compatibility.js";
 
 if (typeof PDFJSDev !== "undefined" && !PDFJSDev.test("CHROME || GENERIC")) {
@@ -68,10 +67,10 @@ class DownloadManager {
    * @returns {boolean} Indicating if the data was opened.
    */
   openOrDownloadData(element, data, filename) {
-    const isPdfFile = PdfFileRegExp.test(filename);
-    const contentType = isPdfFile ? "application/pdf" : "";
+    const isPdfData = isPdfFile(filename);
+    const contentType = isPdfData ? "application/pdf" : "";
 
-    if (isPdfFile && !viewerCompatibilityParams.disableCreateObjectURL) {
+    if (isPdfData && !viewerCompatibilityParams.disableCreateObjectURL) {
       let blobUrl = this._openBlobUrls.get(element);
       if (!blobUrl) {
         blobUrl = URL.createObjectURL(new Blob([data], { type: contentType }));

web/firefoxcom.js

@@ -14,10 +14,10 @@
  */
 
 import "../extensions/firefox/tools/l10n.js";
-import { DEFAULT_SCALE_VALUE, PdfFileRegExp } from "./ui_utils.js";
 import { DefaultExternalServices, PDFViewerApplication } from "./app.js";
-import { PDFDataRangeTransport, shadow } from "pdfjs-lib";
+import { isPdfFile, PDFDataRangeTransport, shadow } from "pdfjs-lib";
 import { BasePreferences } from "./preferences.js";
+import { DEFAULT_SCALE_VALUE } from "./ui_utils.js";
 
 if (typeof PDFJSDev === "undefined" || !PDFJSDev.test("MOZCENTRAL")) {
   throw new Error(
@@ -129,10 +129,10 @@ class DownloadManager {
    * @returns {boolean} Indicating if the data was opened.
    */
   openOrDownloadData(element, data, filename) {
-    const isPdfFile = PdfFileRegExp.test(filename);
-    const contentType = isPdfFile ? "application/pdf" : "";
+    const isPdfData = isPdfFile(filename);
+    const contentType = isPdfData ? "application/pdf" : "";
 
-    if (isPdfFile) {
+    if (isPdfData) {
       let blobUrl = this._openBlobUrls.get(element);
       if (!blobUrl) {
         blobUrl = URL.createObjectURL(new Blob([data], { type: contentType }));
@@ -332,7 +332,8 @@ class FirefoxExternalServices extends DefaultExternalServices {
           pdfDataRangeTransport = new FirefoxComDataRangeTransport(
             args.length,
             args.data,
-            args.done
+            args.done,
+            args.filename
           );
 
           callbacks.onOpenWithTransport(
@@ -367,7 +368,7 @@ class FirefoxExternalServices extends DefaultExternalServices {
             callbacks.onError(args.errorCode);
             break;
           }
-          callbacks.onOpenWithData(args.data);
+          callbacks.onOpenWithData(args.data, args.filename);
           break;
       }
     });

web/pdf_attachment_viewer.js

@@ -119,8 +119,8 @@ class PDFAttachmentViewer extends BaseTreeViewer {
     let attachmentsCount = 0;
     for (const name of names) {
       const item = attachments[name];
-      const content = item.content;
-      const filename = getFilenameFromUrl(item.filename);
+      const content = item.content,
+        filename = getFilenameFromUrl(item.filename);
 
       const div = document.createElement("div");
       div.className = "treeItem";

web/ui_utils.js

@@ -69,9 +69,6 @@ const SpreadMode = {
 // Used by `PDFViewerApplication`, and by the API unit-tests.
 const AutoPrintRegExp = /\bprint\s*\(/;
 
-// Used by the (various) `DownloadManager`-implementations.
-const PdfFileRegExp = /\.pdf$/i;
-
 // Replaces {{arguments}} with their values.
 function formatL10nValue(text, args) {
   if (!args) {
@@ -1062,7 +1059,6 @@ export {
   normalizeWheelEventDirection,
   NullL10n,
   parseQueryString,
-  PdfFileRegExp,
   PresentationModeState,
   ProgressBar,
   RendererType,