Merge pull request #13042 from Snuffleupagus/PDFScriptingManager

[api-minor] Move the viewer scripting initialization/handling into a new `PDFScriptingManager` class

examples/components/simpleviewer.js

@@ -31,8 +31,14 @@ var CMAP_URL = "../../node_modules/pdfjs-dist/cmaps/";
 var CMAP_PACKED = true;
 
 var DEFAULT_URL = "../../web/compressed.tracemonkey-pldi-09.pdf";
+// To test the AcroForm and/or scripting functionality, try e.g. this file:
+// var DEFAULT_URL = "../../test/pdfs/160F-2019.pdf";
+
 var SEARCH_FOR = ""; // try 'Mozilla';
 
+// For scripting support, note also `enableScripting` below.
+var SANDBOX_BUNDLE_SRC = "../../node_modules/pdfjs-dist/build/pdf.sandbox.js";
+
 var container = document.getElementById("viewerContainer");
 
 var eventBus = new pdfjsViewer.EventBus();
@@ -48,13 +54,22 @@ var pdfFindController = new pdfjsViewer.PDFFindController({
   linkService: pdfLinkService,
 });
 
+// (Optionally) enable scripting support.
+var pdfScriptingManager = new pdfjsViewer.PDFScriptingManager({
+  eventBus,
+  sandboxBundleSrc: SANDBOX_BUNDLE_SRC,
+});
+
 var pdfViewer = new pdfjsViewer.PDFViewer({
   container,
   eventBus,
   linkService: pdfLinkService,
   findController: pdfFindController,
+  scriptingManager: pdfScriptingManager,
+  enableScripting: true,
 });
 pdfLinkService.setViewer(pdfViewer);
+pdfScriptingManager.setViewer(pdfViewer);
 
 eventBus.on("pagesinit", function () {
   // We can use pdfViewer now, e.g. let's change default scale.

examples/components/singlepageviewer.js

@@ -31,8 +31,14 @@ var CMAP_URL = "../../node_modules/pdfjs-dist/cmaps/";
 var CMAP_PACKED = true;
 
 var DEFAULT_URL = "../../web/compressed.tracemonkey-pldi-09.pdf";
+// To test the AcroForm and/or scripting functionality, try e.g. this file:
+// var DEFAULT_URL = "../../test/pdfs/160F-2019.pdf";
+
 var SEARCH_FOR = ""; // try 'Mozilla';
 
+// For scripting support, note also `enableScripting` below.
+var SANDBOX_BUNDLE_SRC = "../../node_modules/pdfjs-dist/build/pdf.sandbox.js";
+
 var container = document.getElementById("viewerContainer");
 
 var eventBus = new pdfjsViewer.EventBus();
@@ -48,13 +54,22 @@ var pdfFindController = new pdfjsViewer.PDFFindController({
   linkService: pdfLinkService,
 });
 
+// (Optionally) enable scripting support.
+var pdfScriptingManager = new pdfjsViewer.PDFScriptingManager({
+  eventBus,
+  sandboxBundleSrc: SANDBOX_BUNDLE_SRC,
+});
+
 var pdfSinglePageViewer = new pdfjsViewer.PDFSinglePageViewer({
   container,
   eventBus,
   linkService: pdfLinkService,
   findController: pdfFindController,
+  scriptingManager: pdfScriptingManager,
+  enableScripting: true,
 });
 pdfLinkService.setViewer(pdfSinglePageViewer);
+pdfScriptingManager.setViewer(pdfSinglePageViewer);
 
 eventBus.on("pagesinit", function () {
   // We can use pdfSinglePageViewer now, e.g. let's change default scale.

web/app.js

@@ -16,6 +16,8 @@
 
 import {
   animationStarted,
+  apiPageLayoutToSpreadMode,
+  apiPageModeToSidebarView,
   AutoPrintRegExp,
   DEFAULT_SCALE_VALUE,
   EventBus,
@@ -69,6 +71,7 @@ import { PDFLayerViewer } from "./pdf_layer_viewer.js";
 import { PDFLinkService } from "./pdf_link_service.js";
 import { PDFOutlineViewer } from "./pdf_outline_viewer.js";
 import { PDFPresentationMode } from "./pdf_presentation_mode.js";
+import { PDFScriptingManager } from "./pdf_scripting_manager.js";
 import { PDFSidebar } from "./pdf_sidebar.js";
 import { PDFSidebarResizer } from "./pdf_sidebar_resizer.js";
 import { PDFThumbnailViewer } from "./pdf_thumbnail_viewer.js";
@@ -226,6 +229,8 @@ const PDFViewerApplication = {
   pdfLayerViewer: null,
   /** @type {PDFCursorTools} */
   pdfCursorTools: null,
+  /** @type {PDFScriptingManager} */
+  pdfScriptingManager: null,
   /** @type {ViewHistory} */
   store: null,
   /** @type {DownloadManager} */
@@ -257,8 +262,6 @@ const PDFViewerApplication = {
   _saveInProgress: false,
   _wheelUnusedTicks: 0,
   _idleCallbacks: new Set(),
-  _scriptingInstance: null,
-  _mouseState: Object.create(null),
 
   // Called once when the document is loaded.
   async initialize(appConfig) {
@@ -482,6 +485,18 @@ const PDFViewerApplication = {
     });
     this.findController = findController;
 
+    const pdfScriptingManager = new PDFScriptingManager({
+      eventBus,
+      sandboxBundleSrc:
+        typeof PDFJSDev === "undefined" ||
+        PDFJSDev.test("!PRODUCTION || GENERIC || CHROME")
+          ? AppOptions.get("sandboxBundleSrc")
+          : null,
+      scriptingFactory: this.externalServices,
+      docPropertiesLookup: this._scriptingDocProperties.bind(this),
+    });
+    this.pdfScriptingManager = pdfScriptingManager;
+
     const container = appConfig.mainContainer;
     const viewer = appConfig.viewerContainer;
     this.pdfViewer = new PDFViewer({
@@ -492,6 +507,7 @@ const PDFViewerApplication = {
       linkService: pdfLinkService,
       downloadManager,
       findController,
+      scriptingManager: pdfScriptingManager,
       renderer: AppOptions.get("renderer"),
       enableWebGL: AppOptions.get("enableWebGL"),
       l10n: this.l10n,
@@ -502,10 +518,10 @@ const PDFViewerApplication = {
       useOnlyCssZoom: AppOptions.get("useOnlyCssZoom"),
       maxCanvasPixels: AppOptions.get("maxCanvasPixels"),
       enableScripting: AppOptions.get("enableScripting"),
-      mouseState: this._mouseState,
     });
     pdfRenderingQueue.setViewer(this.pdfViewer);
     pdfLinkService.setViewer(this.pdfViewer);
+    pdfScriptingManager.setViewer(this.pdfViewer);
 
     this.pdfThumbnailViewer = new PDFThumbnailViewer({
       container: appConfig.sidebar.thumbnailView,
@@ -772,32 +788,6 @@ const PDFViewerApplication = {
     this._idleCallbacks.clear();
   },
 
-  /**
-   * @private
-   */
-  async _destroyScriptingInstance() {
-    if (!this._scriptingInstance) {
-      return;
-    }
-    const { scripting, internalEvents, domEvents } = this._scriptingInstance;
-    try {
-      await scripting.destroySandbox();
-    } catch (ex) {}
-
-    for (const [name, listener] of internalEvents) {
-      this.eventBus._off(name, listener);
-    }
-    internalEvents.clear();
-
-    for (const [name, listener] of domEvents) {
-      window.removeEventListener(name, listener);
-    }
-    domEvents.clear();
-
-    delete this._mouseState.isDown;
-    this._scriptingInstance = null;
-  },
-
   /**
    * Closes opened PDF document.
    * @returns {Promise} - Returns the promise, which is resolved when all
@@ -841,7 +831,7 @@ const PDFViewerApplication = {
     this._saveInProgress = false;
 
     this._cancelIdleCallbacks();
-    promises.push(this._destroyScriptingInstance());
+    promises.push(this.pdfScriptingManager.destroyPromise);
 
     this.pdfSidebar.reset();
     this.pdfOutlineViewer.reset();
@@ -1000,11 +990,7 @@ const PDFViewerApplication = {
       return;
     }
     this._saveInProgress = true;
-
+    await this.pdfScriptingManager.dispatchWillSave();
-    await this._scriptingInstance?.scripting.dispatchEventInSandbox({
-      id: "doc",
-      name: "WillSave",
-    });
 
     this.pdfDocument
       .saveDocument(this.pdfDocument.annotationStorage)
@@ -1016,11 +1002,7 @@ const PDFViewerApplication = {
         this.download({ sourceEventType });
       })
       .finally(async () => {
-        await this._scriptingInstance?.scripting.dispatchEventInSandbox({
+        await this.pdfScriptingManager.dispatchDidSave();
-          id: "doc",
-          name: "DidSave",
-        });
-
         this._saveInProgress = false;
       });
   },
@@ -1419,7 +1401,6 @@ const PDFViewerApplication = {
         );
         this._idleCallbacks.add(callback);
       }
-      this._initializeJavaScript(pdfDocument);
     });
 
     this._initializePageLabels(pdfDocument);
@@ -1429,40 +1410,7 @@ const PDFViewerApplication = {
   /**
    * @private
    */
-  async _initializeJavaScript(pdfDocument) {
+  async _scriptingDocProperties(pdfDocument) {
-    if (!AppOptions.get("enableScripting")) {
-      return;
-    }
-    const [objects, calculationOrder, docActions] = await Promise.all([
-      pdfDocument.getFieldObjects(),
-      pdfDocument.getCalculationOrderIds(),
-      pdfDocument.getJSActions(),
-    ]);
-
-    if (!objects && !docActions) {
-      // No FieldObjects or JavaScript actions were found in the document.
-      return;
-    }
-    if (pdfDocument !== this.pdfDocument) {
-      return; // The document was closed while the data resolved.
-    }
-    const scripting = this.externalServices.createScripting(
-      typeof PDFJSDev === "undefined" ||
-        PDFJSDev.test("!PRODUCTION || GENERIC || CHROME")
-        ? { sandboxBundleSrc: AppOptions.get("sandboxBundleSrc") }
-        : null
-    );
-    // Store a reference to the current scripting-instance, to allow destruction
-    // of the sandbox and removal of the event listeners at document closing.
-    const internalEvents = new Map(),
-      domEvents = new Map();
-    this._scriptingInstance = {
-      scripting,
-      ready: false,
-      internalEvents,
-      domEvents,
-    };
-
     if (!this.documentInfo) {
       // It should be *extremely* rare for metadata to not have been resolved
       // when this code runs, but ensure that we handle that case here.
@@ -1470,7 +1418,7 @@ const PDFViewerApplication = {
         this.eventBus._on("metadataloaded", resolve, { once: true });
       });
       if (pdfDocument !== this.pdfDocument) {
-        return; // The document was closed while the metadata resolved.
+        return null; // The document was closed while the metadata resolved.
       }
     }
     if (!this._contentLength) {
@@ -1483,170 +1431,20 @@ const PDFViewerApplication = {
         this.eventBus._on("documentloaded", resolve, { once: true });
       });
       if (pdfDocument !== this.pdfDocument) {
-        return; // The document was closed while the downloadInfo resolved.
+        return null; // The document was closed while the downloadInfo resolved.
       }
     }
 
-    const updateFromSandbox = ({ detail }) => {
+    return {
-      const { id, command, value } = detail;
+      ...this.documentInfo,
-      if (!id) {
+      baseURL: this.baseUrl,
-        switch (command) {
+      filesize: this._contentLength,
-          case "clear":
+      filename: this._docFilename,
-            console.clear();
+      metadata: this.metadata?.getRaw(),
-            break;
+      authors: this.metadata?.get("dc:creator"),
-          case "error":
+      numPages: this.pagesCount,
-            console.error(value);
+      URL: this.url,
-            break;
-          case "layout":
-            this.pdfViewer.spreadMode = apiPageLayoutToSpreadMode(value);
-            break;
-          case "page-num":
-            this.pdfViewer.currentPageNumber = value + 1;
-            break;
-          case "print":
-            this.pdfViewer.pagesPromise.then(() => {
-              this.triggerPrinting();
-            });
-            break;
-          case "println":
-            console.log(value);
-            break;
-          case "zoom":
-            this.pdfViewer.currentScaleValue = value;
-            break;
-        }
-        return;
-      }
-
-      const element = document.getElementById(id);
-      if (element) {
-        element.dispatchEvent(new CustomEvent("updatefromsandbox", { detail }));
-      } else {
-        if (value !== undefined && value !== null) {
-          // The element hasn't been rendered yet, use the AnnotationStorage.
-          pdfDocument.annotationStorage.setValue(id, value);
-        }
-      }
     };
-    internalEvents.set("updatefromsandbox", updateFromSandbox);
-
-    const visitedPages = new Map();
-    const pageOpen = ({ pageNumber, actionsPromise }) => {
-      visitedPages.set(
-        pageNumber,
-        (async () => {
-          // Avoid sending, and thus serializing, the `actions` data
-          // when the same page is opened several times.
-          let actions = null;
-          if (!visitedPages.has(pageNumber)) {
-            actions = await actionsPromise;
-
-            if (pdfDocument !== this.pdfDocument) {
-              return; // The document was closed while the actions resolved.
-            }
-          }
-
-          await this._scriptingInstance?.scripting.dispatchEventInSandbox({
-            id: "page",
-            name: "PageOpen",
-            pageNumber,
-            actions,
-          });
-        })()
-      );
-    };
-
-    const pageClose = async ({ pageNumber }) => {
-      const actionsPromise = visitedPages.get(pageNumber);
-      if (!actionsPromise) {
-        // Ensure that the "pageclose" event was preceded by a "pageopen" event.
-        return;
-      }
-      visitedPages.set(pageNumber, null);
-
-      // Ensure that the "pageopen" event is handled first.
-      await actionsPromise;
-
-      if (pdfDocument !== this.pdfDocument) {
-        return; // The document was closed while the actions resolved.
-      }
-
-      await this._scriptingInstance?.scripting.dispatchEventInSandbox({
-        id: "page",
-        name: "PageClose",
-        pageNumber,
-      });
-    };
-    internalEvents.set("pageopen", pageOpen);
-    internalEvents.set("pageclose", pageClose);
-
-    const dispatchEventInSandbox = ({ detail }) => {
-      scripting.dispatchEventInSandbox(detail);
-    };
-    internalEvents.set("dispatcheventinsandbox", dispatchEventInSandbox);
-
-    const mouseDown = event => {
-      this._mouseState.isDown = true;
-    };
-    domEvents.set("mousedown", mouseDown);
-
-    const mouseUp = event => {
-      this._mouseState.isDown = false;
-    };
-    domEvents.set("mouseup", mouseUp);
-
-    for (const [name, listener] of internalEvents) {
-      this.eventBus._on(name, listener);
-    }
-    for (const [name, listener] of domEvents) {
-      window.addEventListener(name, listener);
-    }
-
-    try {
-      await scripting.createSandbox({
-        objects,
-        calculationOrder,
-        appInfo: {
-          platform: navigator.platform,
-          language: navigator.language,
-        },
-        docInfo: {
-          ...this.documentInfo,
-          baseURL: this.baseUrl,
-          filesize: this._contentLength,
-          filename: this._docFilename,
-          metadata: this.metadata?.getRaw(),
-          authors: this.metadata?.get("dc:creator"),
-          numPages: pdfDocument.numPages,
-          URL: this.url,
-          actions: docActions,
-        },
-      });
-
-      if (this.externalServices.isInAutomation) {
-        this.eventBus.dispatch("sandboxcreated", { source: this });
-      }
-    } catch (error) {
-      console.error(`_initializeJavaScript: "${error?.message}".`);
-
-      this._destroyScriptingInstance();
-      return;
-    }
-
-    await scripting.dispatchEventInSandbox({
-      id: "doc",
-      name: "Open",
-    });
-    await this.pdfViewer.initializeScriptingEvents();
-
-    // Used together with the integration-tests, see the `scriptingReady`
-    // getter, to enable awaiting full initialization of the scripting/sandbox.
-    // (Defer this slightly, to make absolutely sure that everything is done.)
-    Promise.resolve().then(() => {
-      if (this._scriptingInstance) {
-        this._scriptingInstance.ready = true;
-      }
-    });
   },
 
   /**
@@ -1672,7 +1470,7 @@ const PDFViewerApplication = {
   async _initializeAutoPrint(pdfDocument, openActionPromise) {
     const [openAction, javaScript] = await Promise.all([
       openActionPromise,
-      !AppOptions.get("enableScripting") ? pdfDocument.getJavaScript() : null,
+      !this.pdfViewer.enableScripting ? pdfDocument.getJavaScript() : null,
     ]);
 
     if (pdfDocument !== this.pdfDocument) {
@@ -1986,10 +1784,7 @@ const PDFViewerApplication = {
   beforePrint() {
     // Given that the "beforeprint" browser event is synchronous, we
     // unfortunately cannot await the scripting event dispatching here.
-    this._scriptingInstance?.scripting.dispatchEventInSandbox({
+    this.pdfScriptingManager.dispatchWillPrint();
-      id: "doc",
-      name: "WillPrint",
-    });
 
     if (this.printService) {
       // There is no way to suppress beforePrint/afterPrint events,
@@ -2042,10 +1837,7 @@ const PDFViewerApplication = {
   afterPrint() {
     // Given that the "afterprint" browser event is synchronous, we
     // unfortunately cannot await the scripting event dispatching here.
-    this._scriptingInstance?.scripting.dispatchEventInSandbox({
+    this.pdfScriptingManager.dispatchDidPrint();
-      id: "doc",
-      name: "DidPrint",
-    });
 
     if (this.printService) {
       this.printService.destroy();
@@ -2300,7 +2092,7 @@ const PDFViewerApplication = {
    * initialization of the scripting/sandbox.
    */
   get scriptingReady() {
-    return this._scriptingInstance?.ready || false;
+    return this.pdfScriptingManager.ready;
   },
 };
 
@@ -3350,53 +3142,6 @@ function beforeUnload(evt) {
   return false;
 }
 
-/**
- * Converts API PageLayout values to the format used by `PDFViewer`.
- * NOTE: This is supported to the extent that the viewer implements the
- *       necessary Scroll/Spread modes (since SinglePage, TwoPageLeft,
- *       and TwoPageRight all suggests using non-continuous scrolling).
- * @param {string} mode - The API PageLayout value.
- * @returns {number} A value from {SpreadMode}.
- */
-function apiPageLayoutToSpreadMode(layout) {
-  switch (layout) {
-    case "SinglePage":
-    case "OneColumn":
-      return SpreadMode.NONE;
-    case "TwoColumnLeft":
-    case "TwoPageLeft":
-      return SpreadMode.ODD;
-    case "TwoColumnRight":
-    case "TwoPageRight":
-      return SpreadMode.EVEN;
-  }
-  return SpreadMode.NONE; // Default value.
-}
-
-/**
- * Converts API PageMode values to the format used by `PDFSidebar`.
- * NOTE: There's also a "FullScreen" parameter which is not possible to support,
- *       since the Fullscreen API used in browsers requires that entering
- *       fullscreen mode only occurs as a result of a user-initiated event.
- * @param {string} mode - The API PageMode value.
- * @returns {number} A value from {SidebarView}.
- */
-function apiPageModeToSidebarView(mode) {
-  switch (mode) {
-    case "UseNone":
-      return SidebarView.NONE;
-    case "UseThumbs":
-      return SidebarView.THUMBS;
-    case "UseOutlines":
-      return SidebarView.OUTLINE;
-    case "UseAttachments":
-      return SidebarView.ATTACHMENTS;
-    case "UseOC":
-      return SidebarView.LAYERS;
-  }
-  return SidebarView.NONE; // Default value.
-}
-
 /* Abstract factory for the print service. */
 const PDFPrintServiceFactory = {
   instance: {

web/base_viewer.js

@@ -55,6 +55,8 @@ const DEFAULT_CACHE_SIZE = 10;
  *   component.
  * @property {PDFFindController} [findController] - The find controller
  *   component.
+ * @property {PDFScriptingManager} [scriptingManager] - The scripting manager
+ *   component.
  * @property {PDFRenderingQueue} [renderingQueue] - The rendering queue object.
  * @property {boolean} [removePageBorders] - Removes the border shadow around
  *   the pages. The default value is `false`.
@@ -77,10 +79,8 @@ const DEFAULT_CACHE_SIZE = 10;
  *   total pixels, i.e. width * height. Use -1 for no limit. The default value
  *   is 4096 * 4096 (16 mega-pixels).
  * @property {IL10n} l10n - Localization service.
- * @property {boolean} [enableScripting] - Enable embedded script execution.
+ * @property {boolean} [enableScripting] - Enable embedded script execution
- *   The default value is `false`.
+ *   (also requires {scriptingManager} being set). The default value is `false`.
- * @property {Object} [mouseState] - The mouse button state. The default value
- *   is `null`.
  */
 
 function PDFPageViewBuffer(size) {
@@ -183,6 +183,7 @@ class BaseViewer {
     this.linkService = options.linkService || new SimpleLinkService();
     this.downloadManager = options.downloadManager || null;
     this.findController = options.findController || null;
+    this._scriptingManager = options.scriptingManager || null;
     this.removePageBorders = options.removePageBorders || false;
     this.textLayerMode = Number.isInteger(options.textLayerMode)
       ? options.textLayerMode
@@ -195,8 +196,8 @@ class BaseViewer {
     this.useOnlyCssZoom = options.useOnlyCssZoom || false;
     this.maxCanvasPixels = options.maxCanvasPixels;
     this.l10n = options.l10n || NullL10n;
-    this.enableScripting = options.enableScripting || false;
+    this.enableScripting =
-    this._mouseState = options.mouseState || null;
+      options.enableScripting === true && !!this._scriptingManager;
 
     this.defaultRenderingQueue = !options.renderingQueue;
     if (this.defaultRenderingQueue) {
@@ -468,6 +469,12 @@ class BaseViewer {
       if (this.findController) {
         this.findController.setDocument(null);
       }
+      if (this._scriptingManager) {
+        // Defer this slightly, to allow the "pageclose" event to be handled.
+        Promise.resolve().then(() => {
+          this._scriptingManager.setDocument(null);
+        });
+      }
     }
 
     this.pdfDocument = pdfDocument;
@@ -562,6 +569,9 @@ class BaseViewer {
           if (this.findController) {
             this.findController.setDocument(pdfDocument); // Enable searching.
           }
+          if (this.enableScripting) {
+            this._scriptingManager.setDocument(pdfDocument);
+          }
 
           // In addition to 'disableAutoFetch' being set, also attempt to reduce
           // resource usage when loading *very* long/large documents.
@@ -1299,7 +1309,7 @@ class BaseViewer {
       enableScripting,
       hasJSActionsPromise:
         hasJSActionsPromise || this.pdfDocument?.hasJSActions(),
-      mouseState: mouseState || this._mouseState,
+      mouseState: mouseState || this._scriptingManager?.mouseState,
     });
   }
 
@@ -1645,7 +1655,7 @@ class BaseViewer {
     }
     const eventBus = this.eventBus,
       pageOpenPendingSet = (this._pageOpenPendingSet = new Set()),
-      scriptingEvents = (this._scriptingEvents ||= Object.create(null));
+      scriptingEvents = (this._scriptingEvents = Object.create(null));
 
     const dispatchPageClose = pageNumber => {
       if (pageOpenPendingSet.has(pageNumber)) {
@@ -1709,15 +1719,11 @@ class BaseViewer {
 
     // Remove the event listeners.
     eventBus._off("pagechanging", scriptingEvents.onPageChanging);
-    scriptingEvents.onPageChanging = null;
-
     eventBus._off("pagerendered", scriptingEvents.onPageRendered);
-    scriptingEvents.onPageRendered = null;
-
     eventBus._off("pagesdestroy", scriptingEvents.onPagesDestroy);
-    scriptingEvents.onPagesDestroy = null;
 
     this._pageOpenPendingSet = null;
+    this._scriptingEvents = null;
   }
 }
 

web/generic_scripting.js

@@ -13,8 +13,38 @@
  * limitations under the License.
  */
 
+import { getPDFFileNameFromURL } from "./ui_utils.js";
 import { loadScript } from "pdfjs-lib";
 
+async function docPropertiesLookup(pdfDocument) {
+  const url = "",
+    baseUrl = url.split("#")[0];
+  /* eslint-disable prefer-const */
+  let {
+    info,
+    metadata,
+    contentDispositionFilename,
+    contentLength,
+  } = await pdfDocument.getMetadata();
+  /* eslint-enable prefer-const */
+
+  if (!contentLength) {
+    const { length } = await pdfDocument.getDownloadInfo();
+    contentLength = length;
+  }
+
+  return {
+    ...info,
+    baseURL: baseUrl,
+    filesize: contentLength,
+    filename: contentDispositionFilename || getPDFFileNameFromURL(url),
+    metadata: metadata?.getRaw(),
+    authors: metadata?.get("dc:creator"),
+    numPages: pdfDocument.numPages,
+    URL: url,
+  };
+}
+
 class GenericScripting {
   constructor(sandboxBundleSrc) {
     this._ready = loadScript(
@@ -41,4 +71,4 @@ class GenericScripting {
   }
 }
 
-export { GenericScripting };
+export { docPropertiesLookup, GenericScripting };

web/pdf_page_view.js

@@ -105,7 +105,7 @@ class PDFPageView {
     this.renderer = options.renderer || RendererType.CANVAS;
     this.enableWebGL = options.enableWebGL || false;
     this.l10n = options.l10n || NullL10n;
-    this.enableScripting = options.enableScripting || false;
+    this.enableScripting = options.enableScripting === true;
 
     this.paintTask = null;
     this.paintedViewportMap = new WeakMap();

web/pdf_scripting_manager.js

@@ -0,0 +1,406 @@
+/* Copyright 2021 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.
+ */
+
+import { createPromiseCapability, shadow } from "pdfjs-lib";
+import { apiPageLayoutToSpreadMode } from "./ui_utils.js";
+
+/**
+ * @typedef {Object} PDFScriptingManagerOptions
+ * @property {EventBus} eventBus - The application event bus.
+ * @property {string} sandboxBundleSrc - The path and filename of the scripting
+ *   bundle.
+ * @property {Object} [scriptingFactory] - The factory that is used when
+ *   initializing scripting; must contain a `createScripting` method.
+ *   PLEASE NOTE: Primarily intended for the default viewer use-case.
+ * @property {function} [docPropertiesLookup] - The function that is used to
+ *   lookup the necessary document properties.
+ */
+
+class PDFScriptingManager {
+  /**
+   * @param {PDFScriptingManager} options
+   */
+  constructor({
+    eventBus,
+    sandboxBundleSrc = null,
+    scriptingFactory = null,
+    docPropertiesLookup = null,
+  }) {
+    this._pdfDocument = null;
+    this._pdfViewer = null;
+    this._destroyCapability = null;
+
+    this._scripting = null;
+    this._mouseState = Object.create(null);
+    this._ready = false;
+
+    this._eventBus = eventBus;
+    this._sandboxBundleSrc = sandboxBundleSrc;
+    this._scriptingFactory = scriptingFactory;
+    this._docPropertiesLookup = docPropertiesLookup;
+
+    // The default viewer already handles adding/removing of DOM events,
+    // hence limit this to only the viewer components.
+    if (
+      typeof PDFJSDev !== "undefined" &&
+      PDFJSDev.test("COMPONENTS") &&
+      !this._scriptingFactory
+    ) {
+      window.addEventListener("updatefromsandbox", event => {
+        this._eventBus.dispatch("updatefromsandbox", {
+          source: window,
+          detail: event.detail,
+        });
+      });
+    }
+  }
+
+  setViewer(pdfViewer) {
+    this._pdfViewer = pdfViewer;
+  }
+
+  async setDocument(pdfDocument) {
+    if (this._pdfDocument) {
+      await this._destroyScripting();
+    }
+    this._pdfDocument = pdfDocument;
+
+    if (!pdfDocument) {
+      return;
+    }
+    const [objects, calculationOrder, docActions] = await Promise.all([
+      pdfDocument.getFieldObjects(),
+      pdfDocument.getCalculationOrderIds(),
+      pdfDocument.getJSActions(),
+    ]);
+
+    if (!objects && !docActions) {
+      // No FieldObjects or JavaScript actions were found in the document.
+      return;
+    }
+    if (pdfDocument !== this._pdfDocument) {
+      return; // The document was closed while the data resolved.
+    }
+    this._scripting = this._createScripting();
+
+    this._internalEvents.set("updatefromsandbox", event => {
+      this._updateFromSandbox(event.detail);
+    });
+    this._internalEvents.set("dispatcheventinsandbox", event => {
+      this._scripting?.dispatchEventInSandbox(event.detail);
+    });
+
+    this._internalEvents.set("pageopen", event => {
+      this._pageOpen(event.pageNumber, event.actionsPromise);
+    });
+    this._internalEvents.set("pageclose", event => {
+      this._pageClose(event.pageNumber);
+    });
+
+    this._domEvents.set("mousedown", event => {
+      this._mouseState.isDown = true;
+    });
+    this._domEvents.set("mouseup", event => {
+      this._mouseState.isDown = false;
+    });
+
+    for (const [name, listener] of this._internalEvents) {
+      this._eventBus._on(name, listener);
+    }
+    for (const [name, listener] of this._domEvents) {
+      window.addEventListener(name, listener);
+    }
+
+    try {
+      const docProperties = await this._getDocProperties();
+      if (pdfDocument !== this._pdfDocument) {
+        return; // The document was closed while the properties resolved.
+      }
+
+      await this._scripting.createSandbox({
+        objects,
+        calculationOrder,
+        appInfo: {
+          platform: navigator.platform,
+          language: navigator.language,
+        },
+        docInfo: {
+          ...docProperties,
+          actions: docActions,
+        },
+      });
+
+      this._eventBus.dispatch("sandboxcreated", { source: this });
+    } catch (error) {
+      console.error(`PDFScriptingManager.setDocument: "${error?.message}".`);
+
+      await this._destroyScripting();
+      return;
+    }
+
+    await this._scripting?.dispatchEventInSandbox({
+      id: "doc",
+      name: "Open",
+    });
+    await this._pdfViewer.initializeScriptingEvents();
+
+    // Defer this slightly, to ensure that scripting is *fully* initialized.
+    Promise.resolve().then(() => {
+      if (pdfDocument === this._pdfDocument) {
+        this._ready = true;
+      }
+    });
+  }
+
+  async dispatchWillSave(detail) {
+    return this._scripting?.dispatchEventInSandbox({
+      id: "doc",
+      name: "WillSave",
+    });
+  }
+
+  async dispatchDidSave(detail) {
+    return this._scripting?.dispatchEventInSandbox({
+      id: "doc",
+      name: "DidSave",
+    });
+  }
+
+  async dispatchWillPrint(detail) {
+    return this._scripting?.dispatchEventInSandbox({
+      id: "doc",
+      name: "WillPrint",
+    });
+  }
+
+  async dispatchDidPrint(detail) {
+    return this._scripting?.dispatchEventInSandbox({
+      id: "doc",
+      name: "DidPrint",
+    });
+  }
+
+  get mouseState() {
+    return this._mouseState;
+  }
+
+  get destroyPromise() {
+    return this._destroyCapability?.promise || null;
+  }
+
+  get ready() {
+    return this._ready;
+  }
+
+  /**
+   * @private
+   */
+  get _internalEvents() {
+    return shadow(this, "_internalEvents", new Map());
+  }
+
+  /**
+   * @private
+   */
+  get _domEvents() {
+    return shadow(this, "_domEvents", new Map());
+  }
+
+  /**
+   * @private
+   */
+  get _visitedPages() {
+    return shadow(this, "_visitedPages", new Map());
+  }
+
+  /**
+   * @private
+   */
+  _updateFromSandbox(detail) {
+    const { id, command, value } = detail;
+    if (!id) {
+      switch (command) {
+        case "clear":
+          console.clear();
+          break;
+        case "error":
+          console.error(value);
+          break;
+        case "layout":
+          this._pdfViewer.spreadMode = apiPageLayoutToSpreadMode(value);
+          break;
+        case "page-num":
+          this._pdfViewer.currentPageNumber = value + 1;
+          break;
+        case "print":
+          this._pdfViewer.pagesPromise.then(() => {
+            this._eventBus.dispatch("print", { source: this });
+          });
+          break;
+        case "println":
+          console.log(value);
+          break;
+        case "zoom":
+          this._pdfViewer.currentScaleValue = value;
+          break;
+      }
+      return;
+    }
+
+    const element = document.getElementById(id);
+    if (element) {
+      element.dispatchEvent(new CustomEvent("updatefromsandbox", { detail }));
+    } else {
+      if (value !== undefined && value !== null) {
+        // The element hasn't been rendered yet, use the AnnotationStorage.
+        this._pdfDocument?.annotationStorage.setValue(id, value);
+      }
+    }
+  }
+
+  /**
+   * @private
+   */
+  async _pageOpen(pageNumber, actionsPromise) {
+    const pdfDocument = this._pdfDocument,
+      visitedPages = this._visitedPages;
+
+    visitedPages.set(
+      pageNumber,
+      (async () => {
+        // Avoid sending, and thus serializing, the `actions` data when the
+        // *same* page is opened several times.
+        let actions = null;
+        if (!visitedPages.has(pageNumber)) {
+          actions = await actionsPromise;
+          if (pdfDocument !== this._pdfDocument) {
+            return; // The document was closed while the actions resolved.
+          }
+        }
+
+        await this._scripting?.dispatchEventInSandbox({
+          id: "page",
+          name: "PageOpen",
+          pageNumber,
+          actions,
+        });
+      })()
+    );
+  }
+
+  /**
+   * @private
+   */
+  async _pageClose(pageNumber) {
+    const pdfDocument = this._pdfDocument,
+      visitedPages = this._visitedPages;
+
+    const actionsPromise = visitedPages.get(pageNumber);
+    if (!actionsPromise) {
+      // Ensure that the "pageclose" event was preceded by a "pageopen" event.
+      return;
+    }
+    visitedPages.set(pageNumber, null);
+
+    // Ensure that the "pageopen" event is handled first.
+    await actionsPromise;
+    if (pdfDocument !== this._pdfDocument) {
+      return; // The document was closed while the actions resolved.
+    }
+
+    await this._scripting?.dispatchEventInSandbox({
+      id: "page",
+      name: "PageClose",
+      pageNumber,
+    });
+  }
+
+  /**
+   * @returns {Promise<Object>} A promise that is resolved with an {Object}
+   *   containing the necessary document properties; please find the expected
+   *   format in `PDFViewerApplication._scriptingDocProperties`.
+   * @private
+   */
+  async _getDocProperties() {
+    // The default viewer use-case.
+    if (this._docPropertiesLookup) {
+      return this._docPropertiesLookup(this._pdfDocument);
+    }
+    // Fallback, to support the viewer components use-case.
+    if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("COMPONENTS")) {
+      const { docPropertiesLookup } = require("./generic_scripting.js");
+
+      return docPropertiesLookup(this._pdfDocument);
+    }
+    throw new Error("_getDocProperties: Unable to lookup properties.");
+  }
+
+  /**
+   * @private
+   */
+  _createScripting() {
+    this._destroyCapability = createPromiseCapability();
+
+    if (this._scripting) {
+      throw new Error("_createScripting: Scripting already exists.");
+    }
+    if (this._scriptingFactory) {
+      return this._scriptingFactory.createScripting({
+        sandboxBundleSrc: this._sandboxBundleSrc,
+      });
+    }
+    if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("COMPONENTS")) {
+      const { GenericScripting } = require("./generic_scripting.js");
+
+      return new GenericScripting(this._sandboxBundleSrc);
+    }
+    throw new Error("_createScripting: Cannot create scripting.");
+  }
+
+  /**
+   * @private
+   */
+  async _destroyScripting() {
+    this._pdfDocument = null; // Ensure that it's *always* reset synchronously.
+
+    if (!this._scripting) {
+      this._destroyCapability?.resolve();
+      return;
+    }
+    try {
+      await this._scripting.destroySandbox();
+    } catch (ex) {}
+
+    for (const [name, listener] of this._internalEvents) {
+      this._eventBus._off(name, listener);
+    }
+    this._internalEvents.clear();
+
+    for (const [name, listener] of this._domEvents) {
+      window.removeEventListener(name, listener);
+    }
+    this._domEvents.clear();
+
+    this._visitedPages.clear();
+
+    this._scripting = null;
+    delete this._mouseState.isDown;
+    this._ready = false;
+
+    this._destroyCapability?.resolve();
+  }
+}
+
+export { PDFScriptingManager };

web/pdf_viewer.component.js

@@ -29,6 +29,7 @@ import { NullL10n } from "./l10n_utils.js";
 import { PDFFindController } from "./pdf_find_controller.js";
 import { PDFHistory } from "./pdf_history.js";
 import { PDFPageView } from "./pdf_page_view.js";
+import { PDFScriptingManager } from "./pdf_scripting_manager.js";
 import { PDFSinglePageViewer } from "./pdf_single_page_viewer.js";
 import { PDFViewer } from "./pdf_viewer.js";
 
@@ -49,6 +50,7 @@ export {
   PDFHistory,
   PDFLinkService,
   PDFPageView,
+  PDFScriptingManager,
   PDFSinglePageViewer,
   PDFViewer,
   ProgressBar,

web/ui_utils.js

@@ -1001,8 +1001,57 @@ function getActiveOrFocusedElement() {
   return curActiveOrFocused;
 }
 
+/**
+ * Converts API PageLayout values to the format used by `BaseViewer`.
+ * NOTE: This is supported to the extent that the viewer implements the
+ *       necessary Scroll/Spread modes (since SinglePage, TwoPageLeft,
+ *       and TwoPageRight all suggests using non-continuous scrolling).
+ * @param {string} mode - The API PageLayout value.
+ * @returns {number} A value from {SpreadMode}.
+ */
+function apiPageLayoutToSpreadMode(layout) {
+  switch (layout) {
+    case "SinglePage":
+    case "OneColumn":
+      return SpreadMode.NONE;
+    case "TwoColumnLeft":
+    case "TwoPageLeft":
+      return SpreadMode.ODD;
+    case "TwoColumnRight":
+    case "TwoPageRight":
+      return SpreadMode.EVEN;
+  }
+  return SpreadMode.NONE; // Default value.
+}
+
+/**
+ * Converts API PageMode values to the format used by `PDFSidebar`.
+ * NOTE: There's also a "FullScreen" parameter which is not possible to support,
+ *       since the Fullscreen API used in browsers requires that entering
+ *       fullscreen mode only occurs as a result of a user-initiated event.
+ * @param {string} mode - The API PageMode value.
+ * @returns {number} A value from {SidebarView}.
+ */
+function apiPageModeToSidebarView(mode) {
+  switch (mode) {
+    case "UseNone":
+      return SidebarView.NONE;
+    case "UseThumbs":
+      return SidebarView.THUMBS;
+    case "UseOutlines":
+      return SidebarView.OUTLINE;
+    case "UseAttachments":
+      return SidebarView.ATTACHMENTS;
+    case "UseOC":
+      return SidebarView.LAYERS;
+  }
+  return SidebarView.NONE; // Default value.
+}
+
 export {
   animationStarted,
+  apiPageLayoutToSpreadMode,
+  apiPageModeToSidebarView,
   approximateFraction,
   AutoPrintRegExp,
   backtrackBeforeAllVisibleElements, // only exported for testing