Address the final round of review comments for Content-Disposition filename extraction

This patch updates the `IPDFStreamReader` interface and ensures that the interface/implementation of `network.js`, `fetch_stream.js`, `node_stream.js`, and `transport_stream.js` all match properly.
The unit-tests are also adjusted, to more closely replicate the actual behaviour of the various actual `IPDFStreamReader` implementations.
Finally, this patch adjusts the use of the Content-Disposition filename when setting the title in the viewer, and adds `PDFDocumentProperties` support as well.

src/core/worker.js

@@ -103,6 +103,16 @@ IPDFStreamReader.prototype = {
     return null;
   },
 
+  /**
+   * Gets the Content-Disposition filename. It is defined after the headersReady
+   * promise is resolved.
+   * @returns {string|null} The filename, or `null` if the Content-Disposition
+   *                        header is missing/invalid.
+   */
+  get filename() {
+    return null;
+  },
+
   /**
    * Gets PDF binary data length. It is defined after the headersReady promise
    * is resolved.

src/display/api.js

@@ -1997,14 +1997,14 @@ var WorkerTransport = (function WorkerTransportClosure() {
 
     getMetadata: function WorkerTransport_getMetadata() {
       return this.messageHandler.sendWithPromise('GetMetadata', null).
-        then(function transportMetadata(results) {
+          then((results) => {
         return {
           info: results[0],
           metadata: (results[1] ? new Metadata(results[1]) : null),
-          contentDispositionFileName: (this._fullReader ?
-                                       this._fullReader.fileName : null),
+          contentDispositionFilename: (this._fullReader ?
+                                       this._fullReader.filename : null),
         };
-      }.bind(this));
+      });
     },
 
     getStats: function WorkerTransport_getStats() {

src/display/fetch_stream.js

@@ -67,9 +67,9 @@ class PDFFetchStream {
 class PDFFetchStreamReader {
   constructor(stream) {
     this._stream = stream;
-    this._fileName = null;
     this._reader = null;
     this._loaded = 0;
+    this._filename = null;
     let source = stream.source;
     this._withCredentials = source.withCredentials;
     this._contentLength = source.length;
@@ -104,7 +104,6 @@ class PDFFetchStreamReader {
       const getResponseHeader = (name) => {
         return response.headers.get(name);
       };
-
       let { allowRangeRequests, suggestedLength, } =
         validateRangeRequestCapabilities({
           getResponseHeader,
@@ -115,7 +114,8 @@ class PDFFetchStreamReader {
 
       this._contentLength = suggestedLength;
       this._isRangeSupported = allowRangeRequests;
-      this._fileName = extractFilenameFromHeader(getResponseHeader);
+
+      this._filename = extractFilenameFromHeader(getResponseHeader);
 
       // We need to stop reading when range is supported and streaming is
       // disabled.
@@ -131,12 +131,12 @@ class PDFFetchStreamReader {
     return this._headersCapability.promise;
   }
 
-  get contentLength() {
-    return this._contentLength;
+  get filename() {
+    return this._filename;
   }
 
-  get fileName() {
-    return this._fileName;
+  get contentLength() {
+    return this._contentLength;
   }
 
   get isRangeSupported() {

src/display/network.js

@@ -341,7 +341,7 @@ function PDFNetworkStreamFullRequestReader(manager, source) {
   this._requests = [];
   this._done = false;
   this._storedError = undefined;
-  this._fileName = null;
+  this._filename = null;
 
   this.onProgress = null;
 }
@@ -371,6 +371,8 @@ PDFNetworkStreamFullRequestReader.prototype = {
       this._isRangeSupported = true;
     }
 
+    this._filename = extractFilenameFromHeader(getResponseHeader);
+
     var networkManager = this._manager;
     if (networkManager.isStreamingRequest(fullRequestXhrId)) {
       // We can continue fetching when progressive loading is enabled,
@@ -385,11 +387,6 @@ PDFNetworkStreamFullRequestReader.prototype = {
       networkManager.abortRequest(fullRequestXhrId);
     }
 
-    // Content-Disposition: attachment; filename=Naïve file.txt
-    if (networkManager.isPendingRequest(fullRequestXhrId)) {
-      this._fileName = extractFilenameFromHeader(getResponseHeader);
-    }
-
     this._headersReceivedCapability.resolve();
   },
 
@@ -438,8 +435,8 @@ PDFNetworkStreamFullRequestReader.prototype = {
     }
   },
 
-  get fileName() {
-    return this._fileName;
+  get filename() {
+    return this._filename;
   },
 
   get isRangeSupported() {

src/display/network_utils.js

@@ -53,6 +53,18 @@ function validateRangeRequestCapabilities({ getResponseHeader, isHttp,
   return returnValues;
 }
 
+function extractFilenameFromHeader(getResponseHeader) {
+  const contentDisposition = getResponseHeader('Content-Disposition');
+  if (contentDisposition) {
+    let parts =
+      /.+;\s*filename=(?:'|")(.+\.pdf)(?:'|")/gi.exec(contentDisposition);
+    if (parts !== null && parts.length > 1) {
+      return getFilenameFromUrl(parts[1]);
+    }
+  }
+  return null;
+}
+
 function createResponseStatusError(status, url) {
   if (status === 404 || status === 0 && /^file:/.test(url)) {
     return new MissingPDFException('Missing PDF "' + url + '".');
@@ -66,23 +78,9 @@ function validateResponseStatus(status) {
   return status === 200 || status === 206;
 }
 
-function extractFilenameFromHeader(getResponseHeader) {
-  const contentDisposition = getResponseHeader('Content-Disposition');
-
-  if (contentDisposition) {
-    let parts =
-      /.+;\s*filename=(?:"|')(.+\.pdf)(?:"|')/gi.exec(contentDisposition);
-    if (parts !== null && parts.length > 1) {
-      return getFilenameFromUrl(parts[1]);
-    }
-  }
-
-  return null;
-}
-
 export {
   createResponseStatusError,
+  extractFilenameFromHeader,
   validateRangeRequestCapabilities,
   validateResponseStatus,
-  extractFilenameFromHeader,
 };

src/display/node_stream.js

@@ -76,11 +76,11 @@ class BaseFullReader {
     this._done = false;
     this._errored = false;
     this._reason = null;
-    this._fileName = null;
     this.onProgress = null;
     let source = stream.source;
     this._contentLength = source.length; // optional
     this._loaded = 0;
+    this._filename = null;
 
     this._disableRange = source.disableRange || false;
     this._rangeChunkSize = source.rangeChunkSize;
@@ -100,6 +100,10 @@ class BaseFullReader {
     return this._headersCapability.promise;
   }
 
+  get filename() {
+    return this._filename;
+  }
+
   get contentLength() {
     return this._contentLength;
   }
@@ -112,10 +116,6 @@ class BaseFullReader {
     return this._isStreamingSupported;
   }
 
-  get fileName() {
-    return this._fileName;
-  }
-
   read() {
     return this._readCapability.promise.then(() => {
       if (this._done) {
@@ -296,14 +296,13 @@ class PDFNodeStreamFullReader extends BaseFullReader {
         // here: https://nodejs.org/api/http.html#http_message_headers.
         return this._readableStream.headers[name.toLowerCase()];
       };
-
       let { allowRangeRequests, suggestedLength, } =
-      validateRangeRequestCapabilities({
-        getResponseHeader,
-        isHttp: stream.isHttp,
-        rangeChunkSize: this._rangeChunkSize,
-        disableRange: this._disableRange,
-      });
+        validateRangeRequestCapabilities({
+          getResponseHeader,
+          isHttp: stream.isHttp,
+          rangeChunkSize: this._rangeChunkSize,
+          disableRange: this._disableRange,
+        });
 
       if (allowRangeRequests) {
         this._isRangeSupported = true;
@@ -311,8 +310,7 @@ class PDFNodeStreamFullReader extends BaseFullReader {
       // Setting right content length.
       this._contentLength = suggestedLength;
 
-      // Setting the file name from the response header
-      this._fileName = extractFilenameFromHeader(getResponseHeader);
+      this._filename = extractFilenameFromHeader(getResponseHeader);
     };
 
     this._request = null;

src/display/transport_stream.js

@@ -119,6 +119,7 @@ var PDFDataTransportStream = (function PDFDataTransportStreamClosure() {
   function PDFDataTransportStreamReader(stream, queuedChunks) {
     this._stream = stream;
     this._done = false;
+    this._filename = null;
     this._queuedChunks = queuedChunks || [];
     this._requests = [];
     this._headersReady = Promise.resolve();
@@ -143,6 +144,10 @@ var PDFDataTransportStream = (function PDFDataTransportStreamClosure() {
       return this._headersReady;
     },
 
+    get filename() {
+      return this._filename;
+    },
+
     get isRangeSupported() {
       return this._stream._isRangeSupported;
     },