lib/core/worker.js

/**
 * @licstart The following is the entire license notice for the
 * Javascript code in this page
 *
 * Copyright 2020 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * @licend The above is the entire license notice for the
 * Javascript code in this page
 */
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.WorkerMessageHandler = exports.WorkerTask = void 0;

var _util = require("../shared/util.js");

var _primitives = require("./primitives.js");

var _pdf_manager = require("./pdf_manager.js");

var _writer = require("./writer.js");

var _is_node = require("../shared/is_node.js");

var _message_handler = require("../shared/message_handler.js");

var _worker_stream = require("./worker_stream.js");

var _core_utils = require("./core_utils.js");

class WorkerTask {
  constructor(name) {
    this.name = name;
    this.terminated = false;
    this._capability = (0, _util.createPromiseCapability)();
  }

  get finished() {
    return this._capability.promise;
  }

  finish() {
    this._capability.resolve();
  }

  terminate() {
    this.terminated = true;
  }

  ensureNotTerminated() {
    if (this.terminated) {
      throw new Error("Worker task was terminated");
    }
  }

}

exports.WorkerTask = WorkerTask;

class WorkerMessageHandler {
  static setup(handler, port) {
    var testMessageProcessed = false;
    handler.on("test", function wphSetupTest(data) {
      if (testMessageProcessed) {
        return;
      }

      testMessageProcessed = true;

      if (!(data instanceof Uint8Array)) {
        handler.send("test", null);
        return;
      }

      const supportTransfers = data[0] === 255;
      handler.postMessageTransfers = supportTransfers;
      handler.send("test", {
        supportTransfers
      });
    });
    handler.on("configure", function wphConfigure(data) {
      (0, _util.setVerbosityLevel)(data.verbosity);
    });
    handler.on("GetDocRequest", function wphSetupDoc(data) {
      return WorkerMessageHandler.createDocumentHandler(data, port);
    });
  }

  static createDocumentHandler(docParams, port) {
    var pdfManager;
    var terminated = false;
    var cancelXHRs = null;
    var WorkerTasks = [];
    const verbosity = (0, _util.getVerbosityLevel)();
    const apiVersion = docParams.apiVersion;
    const workerVersion = '2.6.347';

    if (apiVersion !== workerVersion) {
      throw new Error(`The API version "${apiVersion}" does not match ` + `the Worker version "${workerVersion}".`);
    }

    const enumerableProperties = [];

    for (const property in []) {
      enumerableProperties.push(property);
    }

    if (enumerableProperties.length) {
      throw new Error("The `Array.prototype` contains unexpected enumerable properties: " + enumerableProperties.join(", ") + "; thus breaking e.g. `for...in` iteration of `Array`s.");
    }

    if (typeof ReadableStream === "undefined" || typeof Promise.allSettled === "undefined") {
      throw new Error("The browser/environment lacks native support for critical " + "functionality used by the PDF.js library (e.g. " + "`ReadableStream` and/or `Promise.allSettled`); " + "please use an ES5-compatible build instead.");
    }

    var docId = docParams.docId;
    var docBaseUrl = docParams.docBaseUrl;
    var workerHandlerName = docParams.docId + "_worker";
    var handler = new _message_handler.MessageHandler(workerHandlerName, docId, port);
    handler.postMessageTransfers = docParams.postMessageTransfers;

    function ensureNotTerminated() {
      if (terminated) {
        throw new Error("Worker was terminated");
      }
    }

    function startWorkerTask(task) {
      WorkerTasks.push(task);
    }

    function finishWorkerTask(task) {
      task.finish();
      var i = WorkerTasks.indexOf(task);
      WorkerTasks.splice(i, 1);
    }

    async function loadDocument(recoveryMode) {
      await pdfManager.ensureDoc("checkHeader");
      await pdfManager.ensureDoc("parseStartXRef");
      await pdfManager.ensureDoc("parse", [recoveryMode]);

      if (!recoveryMode) {
        await pdfManager.ensureDoc("checkFirstPage");
      }

      const [numPages, fingerprint] = await Promise.all([pdfManager.ensureDoc("numPages"), pdfManager.ensureDoc("fingerprint")]);
      return {
        numPages,
        fingerprint
      };
    }

    function getPdfManager(data, evaluatorOptions) {
      var pdfManagerCapability = (0, _util.createPromiseCapability)();
      let newPdfManager;
      var source = data.source;

      if (source.data) {
        try {
          newPdfManager = new _pdf_manager.LocalPdfManager(docId, source.data, source.password, evaluatorOptions, docBaseUrl);
          pdfManagerCapability.resolve(newPdfManager);
        } catch (ex) {
          pdfManagerCapability.reject(ex);
        }

        return pdfManagerCapability.promise;
      }

      var pdfStream,
          cachedChunks = [];

      try {
        pdfStream = new _worker_stream.PDFWorkerStream(handler);
      } catch (ex) {
        pdfManagerCapability.reject(ex);
        return pdfManagerCapability.promise;
      }

      var fullRequest = pdfStream.getFullReader();
      fullRequest.headersReady.then(function () {
        if (!fullRequest.isRangeSupported) {
          return;
        }

        var disableAutoFetch = source.disableAutoFetch || fullRequest.isStreamingSupported;
        newPdfManager = new _pdf_manager.NetworkPdfManager(docId, pdfStream, {
          msgHandler: handler,
          password: source.password,
          length: fullRequest.contentLength,
          disableAutoFetch,
          rangeChunkSize: source.rangeChunkSize
        }, evaluatorOptions, docBaseUrl);

        for (let i = 0; i < cachedChunks.length; i++) {
          newPdfManager.sendProgressiveData(cachedChunks[i]);
        }

        cachedChunks = [];
        pdfManagerCapability.resolve(newPdfManager);
        cancelXHRs = null;
      }).catch(function (reason) {
        pdfManagerCapability.reject(reason);
        cancelXHRs = null;
      });
      var loaded = 0;

      var flushChunks = function () {
        var pdfFile = (0, _util.arraysToBytes)(cachedChunks);

        if (source.length && pdfFile.length !== source.length) {
          (0, _util.warn)("reported HTTP length is different from actual");
        }

        try {
          newPdfManager = new _pdf_manager.LocalPdfManager(docId, pdfFile, source.password, evaluatorOptions, docBaseUrl);
          pdfManagerCapability.resolve(newPdfManager);
        } catch (ex) {
          pdfManagerCapability.reject(ex);
        }

        cachedChunks = [];
      };

      var readPromise = new Promise(function (resolve, reject) {
        var readChunk = function ({
          value,
          done
        }) {
          try {
            ensureNotTerminated();

            if (done) {
              if (!newPdfManager) {
                flushChunks();
              }

              cancelXHRs = null;
              return;
            }

            loaded += (0, _util.arrayByteLength)(value);

            if (!fullRequest.isStreamingSupported) {
              handler.send("DocProgress", {
                loaded,
                total: Math.max(loaded, fullRequest.contentLength || 0)
              });
            }

            if (newPdfManager) {
              newPdfManager.sendProgressiveData(value);
            } else {
              cachedChunks.push(value);
            }

            fullRequest.read().then(readChunk, reject);
          } catch (e) {
            reject(e);
          }
        };

        fullRequest.read().then(readChunk, reject);
      });
      readPromise.catch(function (e) {
        pdfManagerCapability.reject(e);
        cancelXHRs = null;
      });

      cancelXHRs = function (reason) {
        pdfStream.cancelAllRequests(reason);
      };

      return pdfManagerCapability.promise;
    }

    function setupDoc(data) {
      function onSuccess(doc) {
        ensureNotTerminated();
        handler.send("GetDoc", {
          pdfInfo: doc
        });
      }

      function onFailure(ex) {
        ensureNotTerminated();

        if (ex instanceof _util.PasswordException) {
          var task = new WorkerTask(`PasswordException: response ${ex.code}`);
          startWorkerTask(task);
          handler.sendWithPromise("PasswordRequest", ex).then(function ({
            password
          }) {
            finishWorkerTask(task);
            pdfManager.updatePassword(password);
            pdfManagerReady();
          }).catch(function () {
            finishWorkerTask(task);
            handler.send("DocException", ex);
          });
        } else if (ex instanceof _util.InvalidPDFException || ex instanceof _util.MissingPDFException || ex instanceof _util.UnexpectedResponseException || ex instanceof _util.UnknownErrorException) {
          handler.send("DocException", ex);
        } else {
          handler.send("DocException", new _util.UnknownErrorException(ex.message, ex.toString()));
        }
      }

      function pdfManagerReady() {
        ensureNotTerminated();
        loadDocument(false).then(onSuccess, function (reason) {
          ensureNotTerminated();

          if (!(reason instanceof _core_utils.XRefParseException)) {
            onFailure(reason);
            return;
          }

          pdfManager.requestLoadedStream();
          pdfManager.onLoadedStream().then(function () {
            ensureNotTerminated();
            loadDocument(true).then(onSuccess, onFailure);
          });
        });
      }

      ensureNotTerminated();
      var evaluatorOptions = {
        maxImageSize: data.maxImageSize,
        disableFontFace: data.disableFontFace,
        ignoreErrors: data.ignoreErrors,
        isEvalSupported: data.isEvalSupported,
        fontExtraProperties: data.fontExtraProperties
      };
      getPdfManager(data, evaluatorOptions).then(function (newPdfManager) {
        if (terminated) {
          newPdfManager.terminate(new _util.AbortException("Worker was terminated."));
          throw new Error("Worker was terminated");
        }

        pdfManager = newPdfManager;
        pdfManager.onLoadedStream().then(function (stream) {
          handler.send("DataLoaded", {
            length: stream.bytes.byteLength
          });
        });
      }).then(pdfManagerReady, onFailure);
    }

    handler.on("GetPage", function wphSetupGetPage(data) {
      return pdfManager.getPage(data.pageIndex).then(function (page) {
        return Promise.all([pdfManager.ensure(page, "rotate"), pdfManager.ensure(page, "ref"), pdfManager.ensure(page, "userUnit"), pdfManager.ensure(page, "view")]).then(function ([rotate, ref, userUnit, view]) {
          return {
            rotate,
            ref,
            userUnit,
            view
          };
        });
      });
    });
    handler.on("GetPageIndex", function wphSetupGetPageIndex({
      ref
    }) {
      const pageRef = _primitives.Ref.get(ref.num, ref.gen);

      return pdfManager.ensureCatalog("getPageIndex", [pageRef]);
    });
    handler.on("GetDestinations", function wphSetupGetDestinations(data) {
      return pdfManager.ensureCatalog("destinations");
    });
    handler.on("GetDestination", function wphSetupGetDestination(data) {
      return pdfManager.ensureCatalog("getDestination", [data.id]);
    });
    handler.on("GetPageLabels", function wphSetupGetPageLabels(data) {
      return pdfManager.ensureCatalog("pageLabels");
    });
    handler.on("GetPageLayout", function wphSetupGetPageLayout(data) {
      return pdfManager.ensureCatalog("pageLayout");
    });
    handler.on("GetPageMode", function wphSetupGetPageMode(data) {
      return pdfManager.ensureCatalog("pageMode");
    });
    handler.on("GetViewerPreferences", function (data) {
      return pdfManager.ensureCatalog("viewerPreferences");
    });
    handler.on("GetOpenAction", function (data) {
      return pdfManager.ensureCatalog("openAction");
    });
    handler.on("GetAttachments", function wphSetupGetAttachments(data) {
      return pdfManager.ensureCatalog("attachments");
    });
    handler.on("GetJavaScript", function wphSetupGetJavaScript(data) {
      return pdfManager.ensureCatalog("javaScript");
    });
    handler.on("GetOutline", function wphSetupGetOutline(data) {
      return pdfManager.ensureCatalog("documentOutline");
    });
    handler.on("GetOptionalContentConfig", function (data) {
      return pdfManager.ensureCatalog("optionalContentConfig");
    });
    handler.on("GetPermissions", function (data) {
      return pdfManager.ensureCatalog("permissions");
    });
    handler.on("GetMetadata", function wphSetupGetMetadata(data) {
      return Promise.all([pdfManager.ensureDoc("documentInfo"), pdfManager.ensureCatalog("metadata")]);
    });
    handler.on("GetData", function wphSetupGetData(data) {
      pdfManager.requestLoadedStream();
      return pdfManager.onLoadedStream().then(function (stream) {
        return stream.bytes;
      });
    });
    handler.on("GetStats", function wphSetupGetStats(data) {
      return pdfManager.ensureXRef("stats");
    });
    handler.on("GetAnnotations", function ({
      pageIndex,
      intent
    }) {
      return pdfManager.getPage(pageIndex).then(function (page) {
        return page.getAnnotationsData(intent);
      });
    });
    handler.on("SaveDocument", function ({
      numPages,
      annotationStorage,
      filename
    }) {
      pdfManager.requestLoadedStream();
      const promises = [pdfManager.onLoadedStream()];
      const document = pdfManager.pdfDocument;

      for (let pageIndex = 0; pageIndex < numPages; pageIndex++) {
        promises.push(pdfManager.getPage(pageIndex).then(function (page) {
          const task = new WorkerTask(`Save: page ${pageIndex}`);
          return page.save(handler, task, annotationStorage);
        }));
      }

      return Promise.all(promises).then(([stream, ...refs]) => {
        let newRefs = [];

        for (const ref of refs) {
          newRefs = ref.filter(x => x !== null).reduce((a, b) => a.concat(b), newRefs);
        }

        if (newRefs.length === 0) {
          return stream.bytes;
        }

        const xref = document.xref;
        let newXrefInfo = Object.create(null);

        if (xref.trailer) {
          const _info = Object.create(null);

          const xrefInfo = xref.trailer.get("Info") || null;

          if (xrefInfo) {
            xrefInfo.forEach((key, value) => {
              if ((0, _util.isString)(key) && (0, _util.isString)(value)) {
                _info[key] = (0, _util.stringToPDFString)(value);
              }
            });
          }

          newXrefInfo = {
            rootRef: xref.trailer.getRaw("Root") || null,
            encrypt: xref.trailer.getRaw("Encrypt") || null,
            newRef: xref.getNewRef(),
            infoRef: xref.trailer.getRaw("Info") || null,
            info: _info,
            fileIds: xref.trailer.getRaw("ID") || null,
            startXRef: document.startXRef,
            filename
          };
        }

        xref.resetNewRef();
        return (0, _writer.incrementalUpdate)(stream.bytes, newXrefInfo, newRefs);
      });
    });
    handler.on("GetOperatorList", function wphSetupRenderPage(data, sink) {
      var pageIndex = data.pageIndex;
      pdfManager.getPage(pageIndex).then(function (page) {
        var task = new WorkerTask(`GetOperatorList: page ${pageIndex}`);
        startWorkerTask(task);
        const start = verbosity >= _util.VerbosityLevel.INFOS ? Date.now() : 0;
        page.getOperatorList({
          handler,
          sink,
          task,
          intent: data.intent,
          renderInteractiveForms: data.renderInteractiveForms,
          annotationStorage: data.annotationStorage
        }).then(function (operatorListInfo) {
          finishWorkerTask(task);

          if (start) {
            (0, _util.info)(`page=${pageIndex + 1} - getOperatorList: time=` + `${Date.now() - start}ms, len=${operatorListInfo.length}`);
          }

          sink.close();
        }, function (reason) {
          finishWorkerTask(task);

          if (task.terminated) {
            return;
          }

          handler.send("UnsupportedFeature", {
            featureId: _util.UNSUPPORTED_FEATURES.errorOperatorList
          });
          sink.error(reason);
        });
      });
    }, this);
    handler.on("GetTextContent", function wphExtractText(data, sink) {
      var pageIndex = data.pageIndex;

      sink.onPull = function (desiredSize) {};

      sink.onCancel = function (reason) {};

      pdfManager.getPage(pageIndex).then(function (page) {
        var task = new WorkerTask("GetTextContent: page " + pageIndex);
        startWorkerTask(task);
        const start = verbosity >= _util.VerbosityLevel.INFOS ? Date.now() : 0;
        page.extractTextContent({
          handler,
          task,
          sink,
          normalizeWhitespace: data.normalizeWhitespace,
          combineTextItems: data.combineTextItems
        }).then(function () {
          finishWorkerTask(task);

          if (start) {
            (0, _util.info)(`page=${pageIndex + 1} - getTextContent: time=` + `${Date.now() - start}ms`);
          }

          sink.close();
        }, function (reason) {
          finishWorkerTask(task);

          if (task.terminated) {
            return;
          }

          sink.error(reason);
        });
      });
    });
    handler.on("FontFallback", function (data) {
      return pdfManager.fontFallback(data.id, handler);
    });
    handler.on("Cleanup", function wphCleanup(data) {
      return pdfManager.cleanup(true);
    });
    handler.on("Terminate", function wphTerminate(data) {
      terminated = true;
      const waitOn = [];

      if (pdfManager) {
        pdfManager.terminate(new _util.AbortException("Worker was terminated."));
        const cleanupPromise = pdfManager.cleanup();
        waitOn.push(cleanupPromise);
        pdfManager = null;
      } else {
        (0, _primitives.clearPrimitiveCaches)();
      }

      if (cancelXHRs) {
        cancelXHRs(new _util.AbortException("Worker was terminated."));
      }

      WorkerTasks.forEach(function (task) {
        waitOn.push(task.finished);
        task.terminate();
      });
      return Promise.all(waitOn).then(function () {
        handler.destroy();
        handler = null;
      });
    });
    handler.on("Ready", function wphReady(data) {
      setupDoc(docParams);
      docParams = null;
    });
    return workerHandlerName;
  }

  static initializeFromPort(port) {
    var handler = new _message_handler.MessageHandler("worker", "main", port);
    WorkerMessageHandler.setup(handler, port);
    handler.send("ready", null);
  }

}

exports.WorkerMessageHandler = WorkerMessageHandler;

function isMessagePort(maybePort) {
  return typeof maybePort.postMessage === "function" && "onmessage" in maybePort;
}

if (typeof window === "undefined" && !_is_node.isNodeJS && typeof self !== "undefined" && isMessagePort(self)) {
  WorkerMessageHandler.initializeFromPort(self);
}