Add an abstract BasePDFStream class, that all the old IPDFStream implementations inherit from

Given that there's no less than *five* different, but very similar, implementations this helps reduce code duplication and simplifies maintenance.

Also, spotted during rebasing, pass the `enableHWA` option "correctly" (i.e. as part of the existing `transportParams`) to the `WorkerTransport`-class to keep the constructor simpler.

src/core/chunked_stream.js

@@ -272,17 +272,17 @@ class ChunkedStreamManager {
 
   _requestsByChunk = new Map();
 
-  constructor(pdfNetworkStream, args) {
+  constructor(pdfStream, args) {
     this.length = args.length;
     this.chunkSize = args.rangeChunkSize;
     this.stream = new ChunkedStream(this.length, this.chunkSize, this);
-    this.pdfNetworkStream = pdfNetworkStream;
+    this.pdfStream = pdfStream;
     this.disableAutoFetch = args.disableAutoFetch;
     this.msgHandler = args.msgHandler;
   }
 
   sendRequest(begin, end) {
-    const rangeReader = this.pdfNetworkStream.getRangeReader(begin, end);
+    const rangeReader = this.pdfStream.getRangeReader(begin, end);
 
     let chunks = [];
     return new Promise((resolve, reject) => {
@@ -530,7 +530,7 @@ class ChunkedStreamManager {
 
   abort(reason) {
     this.aborted = true;
-    this.pdfNetworkStream?.cancelAllRequests(reason);
+    this.pdfStream?.cancelAllRequests(reason);
 
     for (const capability of this._promisesByRequest.values()) {
       capability.reject(reason);

src/core/worker.js

@@ -219,23 +219,23 @@ class WorkerMessageHandler {
 
         return new LocalPdfManager(pdfManagerArgs);
       }
-      const pdfStream = new PDFWorkerStream(handler),
+      const pdfStream = new PDFWorkerStream({ msgHandler: handler }),
-        fullRequest = pdfStream.getFullReader();
+        fullReader = pdfStream.getFullReader();
 
       const pdfManagerCapability = Promise.withResolvers();
       let newPdfManager,
         cachedChunks = [],
         loaded = 0;
 
-      fullRequest.headersReady
+      fullReader.headersReady
         .then(function () {
-          if (!fullRequest.isRangeSupported) {
+          if (!fullReader.isRangeSupported) {
             return;
           }
           pdfManagerArgs.source = pdfStream;
-          pdfManagerArgs.length = fullRequest.contentLength;
+          pdfManagerArgs.length = fullReader.contentLength;
           // We don't need auto-fetch when streaming is enabled.
-          pdfManagerArgs.disableAutoFetch ||= fullRequest.isStreamingSupported;
+          pdfManagerArgs.disableAutoFetch ||= fullReader.isStreamingSupported;
 
           newPdfManager = new NetworkPdfManager(pdfManagerArgs);
           // There may be a chance that `newPdfManager` is not initialized for
@@ -282,10 +282,10 @@ class WorkerMessageHandler {
             }
             loaded += value.byteLength;
 
-            if (!fullRequest.isStreamingSupported) {
+            if (!fullReader.isStreamingSupported) {
               handler.send("DocProgress", {
                 loaded,
-                total: Math.max(loaded, fullRequest.contentLength || 0),
+                total: Math.max(loaded, fullReader.contentLength || 0),
               });
             }
 
@@ -294,12 +294,12 @@ class WorkerMessageHandler {
             } else {
               cachedChunks.push(value);
             }
-            fullRequest.read().then(readChunk, reject);
+            fullReader.read().then(readChunk, reject);
           } catch (e) {
             reject(e);
           }
         };
-        fullRequest.read().then(readChunk, reject);
+        fullReader.read().then(readChunk, reject);
       }).catch(function (e) {
         pdfManagerCapability.reject(e);
         cancelXHRs = null;

src/core/worker_stream.js

@@ -13,55 +13,28 @@
  * limitations under the License.
  */
 
-import { assert } from "../shared/util.js";
+import { BasePDFStream } from "../shared/base_pdf_stream.js";
 
-/** @implements {IPDFStream} */
+class PDFWorkerStream extends BasePDFStream {
-class PDFWorkerStream {
+  constructor(source) {
-  constructor(msgHandler) {
+    super(source, PDFWorkerStreamReader, PDFWorkerStreamRangeReader);
-    this._msgHandler = msgHandler;
-    this._contentLength = null;
-    this._fullRequestReader = null;
-    this._rangeRequestReaders = [];
-  }
-
-  getFullReader() {
-    assert(
-      !this._fullRequestReader,
-      "PDFWorkerStream.getFullReader can only be called once."
-    );
-    this._fullRequestReader = new PDFWorkerStreamReader(this._msgHandler);
-    return this._fullRequestReader;
-  }
-
-  getRangeReader(begin, end) {
-    const reader = new PDFWorkerStreamRangeReader(begin, end, this._msgHandler);
-    this._rangeRequestReaders.push(reader);
-    return reader;
-  }
-
-  cancelAllRequests(reason) {
-    this._fullRequestReader?.cancel(reason);
-
-    for (const reader of this._rangeRequestReaders.slice(0)) {
-      reader.cancel(reason);
-    }
   }
 }
 
 /** @implements {IPDFStreamReader} */
 class PDFWorkerStreamReader {
-  constructor(msgHandler) {
+  constructor(stream) {
-    this._msgHandler = msgHandler;
+    const { msgHandler } = stream._source;
     this.onProgress = null;
 
     this._contentLength = null;
     this._isRangeSupported = false;
     this._isStreamingSupported = false;
 
-    const readableStream = this._msgHandler.sendWithStream("GetReader");
+    const readableStream = msgHandler.sendWithStream("GetReader");
     this._reader = readableStream.getReader();
 
-    this._headersReady = this._msgHandler
+    this._headersReady = msgHandler
       .sendWithPromise("ReaderHeadersReady")
       .then(data => {
         this._isStreamingSupported = data.isStreamingSupported;
@@ -103,10 +76,10 @@ class PDFWorkerStreamReader {
 
 /** @implements {IPDFStreamRangeReader} */
 class PDFWorkerStreamRangeReader {
-  constructor(begin, end, msgHandler) {
+  constructor(stream, begin, end) {
-    this._msgHandler = msgHandler;
+    const { msgHandler } = stream._source;
 
-    const readableStream = this._msgHandler.sendWithStream("GetRangeReader", {
+    const readableStream = msgHandler.sendWithStream("GetRangeReader", {
       begin,
       end,
     });

src/display/api.js

@@ -440,6 +440,7 @@ function getDocument(src = {}) {
     ownerDocument,
     pdfBug,
     styleElement,
+    enableHWA,
     loadingParams: {
       disableAutoFetch,
       enableXfa,
@@ -463,7 +464,8 @@ function getDocument(src = {}) {
 
       let networkStream;
       if (rangeTransport) {
-        networkStream = new PDFDataTransportStream(rangeTransport, {
+        networkStream = new PDFDataTransportStream({
+          pdfDataRangeTransport: rangeTransport,
           disableRange,
           disableStream,
         });
@@ -508,8 +510,7 @@ function getDocument(src = {}) {
           task,
           networkStream,
           transportParams,
-          transportFactory,
+          transportFactory
-          enableHWA
         );
         task._transport = transport;
         messageHandler.send("Ready", null);
@@ -2391,8 +2392,16 @@ class PDFWorker {
  * @ignore
  */
 class WorkerTransport {
+  downloadInfoCapability = Promise.withResolvers();
+
+  #fullReader = null;
+
+  #lastProgress = null;
+
   #methodPromises = new Map();
 
+  #networkStream = null;
+
   #pageCache = new Map();
 
   #pagePromises = new Map();
@@ -2403,21 +2412,17 @@ class WorkerTransport {
 
   #pagesMapper = PagesMapper.instance;
 
-  constructor(
+  constructor(messageHandler, loadingTask, networkStream, params, factory) {
-    messageHandler,
-    loadingTask,
-    networkStream,
-    params,
-    factory,
-    enableHWA
-  ) {
     this.messageHandler = messageHandler;
     this.loadingTask = loadingTask;
+    this.#networkStream = networkStream;
+
     this.commonObjs = new PDFObjects();
     this.fontLoader = new FontLoader({
       ownerDocument: params.ownerDocument,
       styleElement: params.styleElement,
     });
+    this.enableHWA = params.enableHWA;
     this.loadingParams = params.loadingParams;
     this._params = params;
 
@@ -2430,12 +2435,6 @@ class WorkerTransport {
     this.destroyed = false;
     this.destroyCapability = null;
 
-    this._networkStream = networkStream;
-    this._fullReader = null;
-    this._lastProgress = null;
-    this.downloadInfoCapability = Promise.withResolvers();
-    this.enableHWA = enableHWA;
-
     this.setupMessageHandler();
 
     this.#pagesMapper.addListener(this.#updateCaches.bind(this));
@@ -2604,7 +2603,7 @@ class WorkerTransport {
       this.filterFactory.destroy();
       TextLayer.cleanup();
 
-      this._networkStream?.cancelAllRequests(
+      this.#networkStream?.cancelAllRequests(
         new AbortException("Worker was terminated.")
       );
 
@@ -2621,18 +2620,18 @@ class WorkerTransport {
 
     messageHandler.on("GetReader", (data, sink) => {
       assert(
-        this._networkStream,
+        this.#networkStream,
-        "GetReader - no `IPDFStream` instance available."
+        "GetReader - no `BasePDFStream` instance available."
       );
-      this._fullReader = this._networkStream.getFullReader();
+      this.#fullReader = this.#networkStream.getFullReader();
-      this._fullReader.onProgress = evt => {
+      this.#fullReader.onProgress = evt => {
-        this._lastProgress = {
+        this.#lastProgress = {
           loaded: evt.loaded,
           total: evt.total,
         };
       };
       sink.onPull = () => {
-        this._fullReader
+        this.#fullReader
           .read()
           .then(function ({ value, done }) {
             if (done) {
@@ -2653,7 +2652,7 @@ class WorkerTransport {
       };
 
       sink.onCancel = reason => {
-        this._fullReader.cancel(reason);
+        this.#fullReader.cancel(reason);
 
         sink.ready.catch(readyReason => {
           if (this.destroyed) {
@@ -2665,18 +2664,18 @@ class WorkerTransport {
     });
 
     messageHandler.on("ReaderHeadersReady", async data => {
-      await this._fullReader.headersReady;
+      await this.#fullReader.headersReady;
 
       const { isStreamingSupported, isRangeSupported, contentLength } =
-        this._fullReader;
+        this.#fullReader;
 
       // If stream or range are disabled, it's our only way to report
       // loading progress.
       if (!isStreamingSupported || !isRangeSupported) {
-        if (this._lastProgress) {
+        if (this.#lastProgress) {
-          loadingTask.onProgress?.(this._lastProgress);
+          loadingTask.onProgress?.(this.#lastProgress);
         }
-        this._fullReader.onProgress = evt => {
+        this.#fullReader.onProgress = evt => {
           loadingTask.onProgress?.({
             loaded: evt.loaded,
             total: evt.total,
@@ -2689,16 +2688,16 @@ class WorkerTransport {
 
     messageHandler.on("GetRangeReader", (data, sink) => {
       assert(
-        this._networkStream,
+        this.#networkStream,
-        "GetRangeReader - no `IPDFStream` instance available."
+        "GetRangeReader - no `BasePDFStream` instance available."
       );
-      const rangeReader = this._networkStream.getRangeReader(
+      const rangeReader = this.#networkStream.getRangeReader(
         data.begin,
         data.end
       );
 
       // When streaming is enabled, it's possible that the data requested here
-      // has already been fetched via the `_fullRequestReader` implementation.
+      // has already been fetched via the `#fullReader` implementation.
       // However, given that the PDF data is loaded asynchronously on the
       // main-thread and then sent via `postMessage` to the worker-thread,
       // it may not have been available during parsing (hence the attempt to
@@ -2706,7 +2705,7 @@ class WorkerTransport {
       //
       // To avoid wasting time and resources here, we'll thus *not* dispatch
       // range requests if the data was already loaded but has not been sent to
-      // the worker-thread yet (which will happen via the `_fullRequestReader`).
+      // the worker-thread yet (which will happen via the `#fullReader`).
       if (!rangeReader) {
         sink.close();
         return;
@@ -2950,7 +2949,7 @@ class WorkerTransport {
           isPureXfa: !!this._htmlForXfa,
           numPages: this._numPages,
           annotationStorage: map,
-          filename: this._fullReader?.filename ?? null,
+          filename: this.#fullReader?.filename ?? null,
         },
         transfer
       )
@@ -3118,8 +3117,8 @@ class WorkerTransport {
       .then(results => ({
         info: results[0],
         metadata: results[1] ? new Metadata(results[1]) : null,
-        contentDispositionFilename: this._fullReader?.filename ?? null,
+        contentDispositionFilename: this.#fullReader?.filename ?? null,
-        contentLength: this._fullReader?.contentLength ?? null,
+        contentLength: this.#fullReader?.contentLength ?? null,
         hasStructTree: results[2],
       }));
     this.#methodPromises.set(name, promise);

src/display/fetch_stream.js

@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-import { AbortException, assert, warn } from "../shared/util.js";
+import { AbortException, warn } from "../shared/util.js";
 import {
   createHeaders,
   createResponseError,
@@ -22,6 +22,7 @@ import {
   validateRangeRequestCapabilities,
   validateResponseStatus,
 } from "./network_utils.js";
+import { BasePDFStream } from "../shared/base_pdf_stream.js";
 
 if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("MOZCENTRAL")) {
   throw new Error(
@@ -51,47 +52,13 @@ function getArrayBuffer(val) {
   return new Uint8Array(val).buffer;
 }
 
-/** @implements {IPDFStream} */
+class PDFFetchStream extends BasePDFStream {
-class PDFFetchStream {
   _responseOrigin = null;
 
   constructor(source) {
-    this.source = source;
+    super(source, PDFFetchStreamReader, PDFFetchStreamRangeReader);
     this.isHttp = /^https?:/i.test(source.url);
     this.headers = createHeaders(this.isHttp, source.httpHeaders);
-
-    this._fullRequestReader = null;
-    this._rangeRequestReaders = [];
-  }
-
-  get _progressiveDataLength() {
-    return this._fullRequestReader?._loaded ?? 0;
-  }
-
-  getFullReader() {
-    assert(
-      !this._fullRequestReader,
-      "PDFFetchStream.getFullReader can only be called once."
-    );
-    this._fullRequestReader = new PDFFetchStreamReader(this);
-    return this._fullRequestReader;
-  }
-
-  getRangeReader(begin, end) {
-    if (end <= this._progressiveDataLength) {
-      return null;
-    }
-    const reader = new PDFFetchStreamRangeReader(this, begin, end);
-    this._rangeRequestReaders.push(reader);
-    return reader;
-  }
-
-  cancelAllRequests(reason) {
-    this._fullRequestReader?.cancel(reason);
-
-    for (const reader of this._rangeRequestReaders.slice(0)) {
-      reader.cancel(reason);
-    }
   }
 }
 
@@ -102,7 +69,7 @@ class PDFFetchStreamReader {
     this._reader = null;
     this._loaded = 0;
     this._filename = null;
-    const source = stream.source;
+    const source = stream._source;
     this._withCredentials = source.withCredentials || false;
     this._contentLength = source.length;
     this._headersCapability = Promise.withResolvers();
@@ -205,7 +172,7 @@ class PDFFetchStreamRangeReader {
   constructor(stream, begin, end) {
     this._stream = stream;
     this._reader = null;
-    const source = stream.source;
+    const source = stream._source;
     this._withCredentials = source.withCredentials || false;
     this._readCapability = Promise.withResolvers();
 

src/display/network.js

@@ -21,6 +21,7 @@ import {
   getResponseOrigin,
   validateRangeRequestCapabilities,
 } from "./network_utils.js";
+import { BasePDFStream } from "../shared/base_pdf_stream.js";
 
 if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("MOZCENTRAL")) {
   throw new Error(
@@ -35,18 +36,13 @@ function getArrayBuffer(val) {
   return typeof val !== "string" ? val : stringToBytes(val).buffer;
 }
 
-/** @implements {IPDFStream} */
+class PDFNetworkStream extends BasePDFStream {
-class PDFNetworkStream {
   #pendingRequests = new WeakMap();
 
-  _fullRequestReader = null;
-
-  _rangeRequestReaders = [];
-
   _responseOrigin = null;
 
   constructor(source) {
-    this._source = source;
+    super(source, PDFNetworkStreamFullReader, PDFNetworkStreamRangeReader);
     this.url = source.url;
     this.isHttp = /^https?:/i.test(this.url);
     this.headers = createHeaders(this.isHttp, source.httpHeaders);
@@ -160,38 +156,18 @@ class PDFNetworkStream {
     }
   }
 
-  getFullReader() {
-    assert(
-      !this._fullRequestReader,
-      "PDFNetworkStream.getFullReader can only be called once."
-    );
-    this._fullRequestReader = new PDFNetworkStreamFullRequestReader(this);
-    return this._fullRequestReader;
-  }
-
   getRangeReader(begin, end) {
-    const reader = new PDFNetworkStreamRangeRequestReader(this, begin, end);
+    const reader = super.getRangeReader(begin, end);
-    reader.onClosed = () => {
-      const i = this._rangeRequestReaders.indexOf(reader);
-      if (i >= 0) {
-        this._rangeRequestReaders.splice(i, 1);
-      }
-    };
-    this._rangeRequestReaders.push(reader);
-    return reader;
-  }
 
-  cancelAllRequests(reason) {
+    if (reader) {
-    this._fullRequestReader?.cancel(reason);
+      reader.onClosed = () => this._rangeReaders.delete(reader);
-
-    for (const reader of this._rangeRequestReaders.slice(0)) {
-      reader.cancel(reason);
     }
+    return reader;
   }
 }
 
 /** @implements {IPDFStreamReader} */
-class PDFNetworkStreamFullRequestReader {
+class PDFNetworkStreamFullReader {
   constructor(stream) {
     this._stream = stream;
     const { disableRange, length, rangeChunkSize } = stream._source;
@@ -355,7 +331,7 @@ class PDFNetworkStreamFullRequestReader {
 }
 
 /** @implements {IPDFStreamRangeReader} */
-class PDFNetworkStreamRangeRequestReader {
+class PDFNetworkStreamRangeReader {
   onClosed = null;
 
   constructor(stream, begin, end) {
@@ -398,7 +374,7 @@ class PDFNetworkStreamRangeRequestReader {
       requestCapability.resolve({ value: undefined, done: true });
     }
     this._requests.length = 0;
-    this.onClosed?.(this);
+    this.onClosed?.();
   }
 
   _onError(status) {
@@ -435,7 +411,7 @@ class PDFNetworkStreamRangeRequestReader {
     this._requests.length = 0;
 
     this._stream._abortRequest(this._requestXhr);
-    this.onClosed?.(this);
+    this.onClosed?.();
   }
 }
 

src/display/node_stream.js

@@ -15,6 +15,7 @@
 /* globals process */
 
 import { AbortException, assert, warn } from "../shared/util.js";
+import { BasePDFStream } from "../shared/base_pdf_stream.js";
 import { createResponseError } from "./network_utils.js";
 
 if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("MOZCENTRAL")) {
@@ -60,47 +61,14 @@ function getArrayBuffer(val) {
   return new Uint8Array(val).buffer;
 }
 
-class PDFNodeStream {
+class PDFNodeStream extends BasePDFStream {
   constructor(source) {
-    this.source = source;
+    super(source, PDFNodeStreamFsFullReader, PDFNodeStreamFsRangeReader);
     this.url = parseUrlOrPath(source.url);
     assert(
       this.url.protocol === "file:",
       "PDFNodeStream only supports file:// URLs."
     );
-
-    this._fullRequestReader = null;
-    this._rangeRequestReaders = [];
-  }
-
-  get _progressiveDataLength() {
-    return this._fullRequestReader?._loaded ?? 0;
-  }
-
-  getFullReader() {
-    assert(
-      !this._fullRequestReader,
-      "PDFNodeStream.getFullReader can only be called once."
-    );
-    this._fullRequestReader = new PDFNodeStreamFsFullReader(this);
-    return this._fullRequestReader;
-  }
-
-  getRangeReader(begin, end) {
-    if (end <= this._progressiveDataLength) {
-      return null;
-    }
-    const rangeReader = new PDFNodeStreamFsRangeReader(this, begin, end);
-    this._rangeRequestReaders.push(rangeReader);
-    return rangeReader;
-  }
-
-  cancelAllRequests(reason) {
-    this._fullRequestReader?.cancel(reason);
-
-    for (const reader of this._rangeRequestReaders.slice(0)) {
-      reader.cancel(reason);
-    }
   }
 }
 
@@ -111,7 +79,7 @@ class PDFNodeStreamFsFullReader {
 
   constructor(stream) {
     this.onProgress = null;
-    const source = stream.source;
+    const source = stream._source;
     this._contentLength = source.length; // optional
     this._loaded = 0;
     this._filename = null;

src/display/transport_stream.js

@@ -13,39 +13,42 @@
  * limitations under the License.
  */
 
-/** @typedef {import("../interfaces").IPDFStream} IPDFStream */
 /** @typedef {import("../interfaces").IPDFStreamReader} IPDFStreamReader */
 // eslint-disable-next-line max-len
 /** @typedef {import("../interfaces").IPDFStreamRangeReader} IPDFStreamRangeReader */
 
 import { assert } from "../shared/util.js";
+import { BasePDFStream } from "../shared/base_pdf_stream.js";
 import { isPdfFile } from "./display_utils.js";
 
-/** @implements {IPDFStream} */
+function getArrayBuffer(val) {
-class PDFDataTransportStream {
+  // Prevent any possible issues by only transferring a Uint8Array that
-  constructor(
+  // completely "utilizes" its underlying ArrayBuffer.
-    pdfDataRangeTransport,
+  return val instanceof Uint8Array && val.byteLength === val.buffer.byteLength
-    { disableRange = false, disableStream = false }
+    ? val.buffer
-  ) {
+    : new Uint8Array(val).buffer;
-    assert(
+}
-      pdfDataRangeTransport,
+
-      'PDFDataTransportStream - missing required "pdfDataRangeTransport" argument.'
+class PDFDataTransportStream extends BasePDFStream {
+  _pdfDataRangeTransport = null;
+
+  _queuedChunks = [];
+
+  constructor(source) {
+    super(
+      source,
+      PDFDataTransportStreamReader,
+      PDFDataTransportStreamRangeReader
     );
+    const { pdfDataRangeTransport, disableRange, disableStream } = source;
     const { length, initialData, progressiveDone, contentDispositionFilename } =
       pdfDataRangeTransport;
 
-    this._queuedChunks = [];
     this._progressiveDone = progressiveDone;
     this._contentDispositionFilename = contentDispositionFilename;
 
     if (initialData?.length > 0) {
-      // Prevent any possible issues by only transferring a Uint8Array that
+      const buffer = getArrayBuffer(initialData);
-      // completely "utilizes" its underlying ArrayBuffer.
-      const buffer =
-        initialData instanceof Uint8Array &&
-        initialData.byteLength === initialData.buffer.byteLength
-          ? initialData.buffer
-          : new Uint8Array(initialData).buffer;
       this._queuedChunks.push(buffer);
     }
 
@@ -54,139 +57,89 @@ class PDFDataTransportStream {
     this._isRangeSupported = !disableRange;
     this._contentLength = length;
 
-    this._fullRequestReader = null;
-    this._rangeReaders = [];
-
     pdfDataRangeTransport.addRangeListener((begin, chunk) => {
-      this._onReceiveData({ begin, chunk });
+      this.#onReceiveData(begin, chunk);
     });
 
     pdfDataRangeTransport.addProgressListener((loaded, total) => {
-      this._onProgress({ loaded, total });
+      if (total !== undefined) {
+        this._fullReader?.onProgress?.({ loaded, total });
+      }
     });
 
     pdfDataRangeTransport.addProgressiveReadListener(chunk => {
-      this._onReceiveData({ chunk });
+      this.#onReceiveData(/* begin = */ undefined, chunk);
     });
 
     pdfDataRangeTransport.addProgressiveDoneListener(() => {
-      this._onProgressiveDone();
+      this._fullReader?.progressiveDone();
+      this._progressiveDone = true;
     });
 
     pdfDataRangeTransport.transportReady();
   }
 
-  _onReceiveData({ begin, chunk }) {
+  #onReceiveData(begin, chunk) {
-    // Prevent any possible issues by only transferring a Uint8Array that
+    const buffer = getArrayBuffer(chunk);
-    // completely "utilizes" its underlying ArrayBuffer.
-    const buffer =
-      chunk instanceof Uint8Array &&
-      chunk.byteLength === chunk.buffer.byteLength
-        ? chunk.buffer
-        : new Uint8Array(chunk).buffer;
 
     if (begin === undefined) {
-      if (this._fullRequestReader) {
+      if (this._fullReader) {
-        this._fullRequestReader._enqueue(buffer);
+        this._fullReader._enqueue(buffer);
       } else {
         this._queuedChunks.push(buffer);
       }
     } else {
-      const found = this._rangeReaders.some(function (rangeReader) {
+      const rangeReader = this._rangeReaders
-        if (rangeReader._begin !== begin) {
+        .keys()
-          return false;
+        .find(r => r._begin === begin);
-        }
+
-        rangeReader._enqueue(buffer);
-        return true;
-      });
       assert(
-        found,
+        rangeReader,
-        "_onReceiveData - no `PDFDataTransportStreamRangeReader` instance found."
+        "#onReceiveData - no `PDFDataTransportStreamRangeReader` instance found."
       );
-    }
+      rangeReader._enqueue(buffer);
-  }
-
-  get _progressiveDataLength() {
-    return this._fullRequestReader?._loaded ?? 0;
-  }
-
-  _onProgress(evt) {
-    if (evt.total !== undefined) {
-      this._fullRequestReader?.onProgress?.({
-        loaded: evt.loaded,
-        total: evt.total,
-      });
-    }
-  }
-
-  _onProgressiveDone() {
-    this._fullRequestReader?.progressiveDone();
-    this._progressiveDone = true;
-  }
-
-  _removeRangeReader(reader) {
-    const i = this._rangeReaders.indexOf(reader);
-    if (i >= 0) {
-      this._rangeReaders.splice(i, 1);
     }
   }
 
   getFullReader() {
-    assert(
+    const reader = super.getFullReader();
-      !this._fullRequestReader,
-      "PDFDataTransportStream.getFullReader can only be called once."
-    );
-    const queuedChunks = this._queuedChunks;
     this._queuedChunks = null;
-    return new PDFDataTransportStreamReader(
+    return reader;
-      this,
-      queuedChunks,
-      this._progressiveDone,
-      this._contentDispositionFilename
-    );
   }
 
   getRangeReader(begin, end) {
-    if (end <= this._progressiveDataLength) {
+    const reader = super.getRangeReader(begin, end);
-      return null;
+
+    if (reader) {
+      reader.onDone = () => this._rangeReaders.delete(reader);
+
+      this._pdfDataRangeTransport.requestDataRange(begin, end);
     }
-    const reader = new PDFDataTransportStreamRangeReader(this, begin, end);
-    this._pdfDataRangeTransport.requestDataRange(begin, end);
-    this._rangeReaders.push(reader);
     return reader;
   }
 
   cancelAllRequests(reason) {
-    this._fullRequestReader?.cancel(reason);
+    super.cancelAllRequests(reason);
 
-    for (const reader of this._rangeReaders.slice(0)) {
-      reader.cancel(reason);
-    }
     this._pdfDataRangeTransport.abort();
   }
 }
 
 /** @implements {IPDFStreamReader} */
 class PDFDataTransportStreamReader {
-  constructor(
+  constructor(stream) {
-    stream,
-    queuedChunks,
-    progressiveDone = false,
-    contentDispositionFilename = null
-  ) {
     this._stream = stream;
-    this._done = progressiveDone || false;
+    this._done = stream._progressiveDone || false;
-    this._filename = isPdfFile(contentDispositionFilename)
+    this._filename = isPdfFile(stream._contentDispositionFilename)
-      ? contentDispositionFilename
+      ? stream._contentDispositionFilename
       : null;
-    this._queuedChunks = queuedChunks || [];
+    this._queuedChunks = stream._queuedChunks || [];
     this._loaded = 0;
     for (const chunk of this._queuedChunks) {
       this._loaded += chunk.byteLength;
     }
     this._requests = [];
     this._headersReady = Promise.resolve();
-    stream._fullRequestReader = this;
 
     this.onProgress = null;
   }
@@ -255,6 +208,8 @@ class PDFDataTransportStreamReader {
 
 /** @implements {IPDFStreamRangeReader} */
 class PDFDataTransportStreamRangeReader {
+  onDone = null;
+
   constructor(stream, begin, end) {
     this._stream = stream;
     this._begin = begin;
@@ -279,7 +234,7 @@ class PDFDataTransportStreamRangeReader {
       this._requests.length = 0;
     }
     this._done = true;
-    this._stream._removeRangeReader(this);
+    this.onDone?.();
   }
 
   async read() {
@@ -302,7 +257,7 @@ class PDFDataTransportStreamRangeReader {
       requestCapability.resolve({ value: undefined, done: true });
     }
     this._requests.length = 0;
-    this._stream._removeRangeReader(this);
+    this.onDone?.();
   }
 }
 

src/shared/base_pdf_stream.js

@@ -13,40 +13,83 @@
  * limitations under the License.
  */
 
+import { assert, unreachable } from "./util.js";
+
 /**
  * Interface that represents PDF data transport. If possible, it allows
  * progressively load entire or fragment of the PDF binary data.
- *
- * @interface
  */
-class IPDFStream {
+class BasePDFStream {
+  #PDFStreamReader = null;
+
+  #PDFStreamRangeReader = null;
+
+  _fullReader = null;
+
+  _rangeReaders = new Set();
+
+  _source = null;
+
+  constructor(source, PDFStreamReader, PDFStreamRangeReader) {
+    if (
+      (typeof PDFJSDev === "undefined" || PDFJSDev.test("TESTING")) &&
+      this.constructor === BasePDFStream
+    ) {
+      unreachable("Cannot initialize BasePDFStream.");
+    }
+    this._source = source;
+
+    this.#PDFStreamReader = PDFStreamReader;
+    this.#PDFStreamRangeReader = PDFStreamRangeReader;
+  }
+
+  get _progressiveDataLength() {
+    return this._fullReader?._loaded ?? 0;
+  }
+
   /**
    * Gets a reader for the entire PDF data.
-   * @returns {IPDFStreamReader}
+   * @returns {BasePDFStreamReader}
    */
   getFullReader() {
-    return null;
+    assert(
+      !this._fullReader,
+      "BasePDFStream.getFullReader can only be called once."
+    );
+    return (this._fullReader = new this.#PDFStreamReader(this));
   }
 
   /**
    * Gets a reader for the range of the PDF data.
    *
    * NOTE: Currently this method is only expected to be invoked *after*
-   * the `IPDFStreamReader.prototype.headersReady` promise has resolved.
+   * the `BasePDFStreamReader.prototype.headersReady` promise has resolved.
    *
    * @param {number} begin - the start offset of the data.
    * @param {number} end - the end offset of the data.
-   * @returns {IPDFStreamRangeReader}
+   * @returns {BasePDFStreamRangeReader}
    */
   getRangeReader(begin, end) {
-    return null;
+    if (end <= this._progressiveDataLength) {
+      return null;
+    }
+    const reader = new this.#PDFStreamRangeReader(this, begin, end);
+    this._rangeReaders.add(reader);
+    return reader;
   }
 
   /**
    * Cancels all opened reader and closes all their opened requests.
    * @param {Object} reason - the reason for cancelling
    */
-  cancelAllRequests(reason) {}
+  cancelAllRequests(reason) {
+    this._fullReader?.cancel(reason);
+
+    // Always create a copy of the rangeReaders.
+    for (const reader of new Set(this._rangeReaders)) {
+      reader.cancel(reason);
+    }
+  }
 }
 
 /**
@@ -152,4 +195,4 @@ class IPDFStreamRangeReader {
   cancel(reason) {}
 }
 
-export { IPDFStream, IPDFStreamRangeReader, IPDFStreamReader };
+export { BasePDFStream, IPDFStreamRangeReader, IPDFStreamReader };

test/unit/common_pdfstream_tests.js

@@ -16,8 +16,7 @@
 import { AbortException, isNodeJS } from "../../src/shared/util.js";
 import { getCrossOriginHostname, TestPdfsServer } from "./test_utils.js";
 
-// Common tests to verify behavior across implementations of the IPDFStream
+// Common tests to verify behavior across `BasePDFStream` implementations:
-// interface:
 // - PDFNetworkStream by network_spec.js
 // - PDFFetchStream by fetch_stream_spec.js
 async function testCrossOriginRedirects({