This replaces the boolean `annotationEditorEnabled` option/preference with a "proper" `annotationEditorMode` one. This way it's not only possible for the user to control if Editing is enabled/disabled, but also which *specific* Editing-mode should become enabled upon PDF document load.
Given that Editing is not enabled/released yet, I cannot imagine that changing the name and type of the option/preference should be an issue.
Given that printing is triggered *synchronously* in browsers, it's thus possible for scripting (in PDF documents) to modify the Annotation-data while printing is currently ongoing.
To work-around that we add a new printing-specific `AnnotationStorage`, where the serializable data is *frozen* upon initialization, which the viewer can thus create/utilize during printing.
For encrypted PDF documents without the required permissions set, this patch adds support for disabling of Annotation-editing. However, please note that it also requires that the `pdfjs.enablePermissions` preference is set to `true` (since PDF document permissions could be seen as user hostile).[1]
As I started looking at the issue, it soon became clear that *only* trying to fix the issue without slightly re-factor the surrounding code would be somewhat difficult.
The following is an overview of the changes in this patch; sorry about the size/scope of this!
- Use a new `AnnotationEditorUIManager`-instance *for each* PDF document opened in the GENERIC viewer, to prevent user-added Annotations from "leaking" from one document into the next.
- Re-factor the `BaseViewer.#initializePermissions`-method, to simplify handling of temporarily disabled modes (e.g. for both Annotation-rendering and Annotation-editing).
- When editing is enabled, let the Editor-buttons be `disabled` until the document has loaded. This way we avoid the buttons becoming clickable temporarily, for PDF documents that use permissions.
- Slightly re-factor how the Editor-buttons are shown/hidden in the viewer, and reset the toolbar-state when a new PDF document is opened.
- Flip the order of the Editor-buttons and the pre-exising toolbarButtons in the "toolbarViewerRight"-div. (To help reduce the size, a little bit, for the PR that adds new Editor-toolbars.)
- Enable editing by default in the development viewer, i.e. `gulp server`, since having to (repeatedly) do that manually becomes annoying after a while.
- Finally, support disabling of editing when `pdfjs.enablePermissions` is set; fixes issue 15049.
---
[1] Either manually with `about:config`, or using e.g. a [Group Policy](https://github.com/mozilla/policy-templates).
Given that the SVG back-end is not defined anywhere except in GENERIC builds, we can remove a little bit of unnecessary code in e.g. the Firefox PDF Viewer.
- Approximate the drawn curve by a set of Bezier curves in using
js code from https://github.com/soswow/fit-curves.
The code has been slightly modified in order to make the linter
happy.
Given the differences between XFA documents and "normal" PDF documents, we don't support editing of the former ones. Hence, when a XFA-document is opened, we temporarily disable the editor-buttons.
Currently, when range-requests and/or streaming are not supported or for documents opened from `data`-URLs, we'll manually set the `contentDispositionFilename` (assuming it exists and is valid) from the `onOpenWithData`-callback in `PDFViewerApplication.initPassiveLoading`.
However, because of a small oversight in `PDFViewerApplication._initializeMetadata`, this *cached* `contentDispositionFilename` would be ignored and we'd only attempt to use the one returned by `PDFDocumentProxy.getMetadata` in the API (which in the cases outlined above will always be empty).
Also, to ensure that the document properties dialog always displays the *correct* fileName we'll now lookup it using the same exact method as in the viewer itself (via a new callback-function).
With the exception of `isThumbnailViewVisible`, these getters are completely unused. Generally speaking, using the `visibleView`-getter directly works just as well and seems (at least to me) to be overall preferable considering how our classes are usually implemented.
Currently, when non-standard `pageColors` are specified, the thumbnails will look inconsistent depending on how they're created.
The thumbnails that are created by downsizing the *page* canvases will obviously use the `pageColors` as intended, however the thumbnails which are rendered *directly* will always use the default colors.
After the changes in https://bugzilla.mozilla.org/show_bug.cgi?id=1757771, that simplified the MOZCENTRAL downloading code, the `sourceEventType` is now completely unused and should thus be removed (in my opinion).
Furthermore, with these changes, we also no longer need a *separate* internal "save"-event and can instead just use the older "download"-event everywhere.
Given that the new API-option is an Object named `pageColors`, with `background`/`foreground` keys, it occurred to me that it'd be slightly more consistent if the options/preferences names fully reflected that.
These methods are completely unused in the Firefox PDF Viewer, and were only added to supplement the `PDFViewerApplication.{bindEvents, bindWindowEvents}`-methods since third-party implementations may apparently need to remove event listeners (see PR 8525).
However, in the MOZCENTRAL build that's just dead code and this patch reduces the size of the *built* `web/viewer.js`-file by `~3.5` kB.
This new CSS variable will allow us to simplify a couple of different viewer components, since we no longer need to use JavaScript-based hacks and can directly set the CSS rules instead. In particular:
- The `BaseViewer`-handling, used as part of the code that will center pages *vertically* in PresentationMode, can be simplified.
By using CSS to control the height of the "dummy"-page we avoid unnecessarily invalidating the scale-value, which can reduce *some* unneeded re-rendering while PresentationMode is active.
- The `SecondaryToolbar.#setMaxHeight`-method, and its associated parameters, are no longer necessary and can be completely removed.
Note that in order for things to work correctly in general, the new `--viewer-container-height` CSS variable must potentially be updated on any window-based "resize"-event (even when there's no zooming). While this is currently only done in the default viewer, that shouldn't be an issue since neither PresentationMode nor Toolbar-functionality is included in the "viewer components".
- Use Canvas & CanvasText color when they don't have their default value
as background and foreground colors.
- The colors used to draw (stroke/fill) in a pdf are replaced by the bg/fg
ones according to their luminance.
There's no point in having these variables defined (implicitly) as `undefined` in e.g. the Firefox PDF Viewer.
By defining them with `var` and using ESList ignores, rather than `let`, we can move them into the relevant pre-processor block instead. Note that since the entire viewer-code is placed, by Webpack, in a top-level closure these variables will thus *not* become globally accessible.
Given that `webViewerOpenFileViaURL` only has a single call-site, and also isn't a particularly large/complex function, it doesn't seem necessary for this to be a separate function and hence it's simply inlined instead.
Also, changes the "no valid build-target was set"-case to throw unconditionally since the only way that it could ever be hit is if there are bugs in the `gulpfile`-code.
Note how both of the openFile-buttons are always hidden during viewer initialization in the MOZCENTRAL build, i.e. the *built-in* Firefox PDF Viewer. Despite that we still include HTML, CSS, and JavaScript code for these buttons in the build.
This patch *reduces* the size of the `gulp mozcentral` output by `1679` bytes, which isn't a lot but still cannot hurt.
Given that none of these CSS rules are used at all, unless debugging is enabled, it seems completely unnecessary to load them *unconditionally* for all users.[1]
Note that if *both* the `textLayer` and `pdfBug` debugging hash-parameters are specified simultaneously, we'll now load the `PDFBug`-file *twice* (since the code is simpler that way). However, given first of all that none of this is enabled by default and secondly that using those parameters together isn't helpful[2], potentially loading that file twice is hopefully not an issue.
For the `gulp mozcentral` target, the size of the *built* `viewer.css` file is reduced `> 3%` with this patch.
---
[1] For the Firefox built-in PDF Viewer, in order to even be able to access the `PDFBug` functionality, you need to first of all set `pdfjs.pdfBugEnabled = true` manually in `about:config`. Secondly, you then also need to append the `pdfBug=...` hash-parameter to the URL when *initially* loading the document.
[2] Note how the `textLayer`-settings are already, since essentially forever, overriding the highlighting-features of the "FontInspector"-tab.
*This is yet another installment in a never-ending series of patches that attempt to simplify and improve old code.*
The `fileInput`-element is used to support the "Open file"-button in the `GENERIC` viewer, however this is very old code.
Rather than creating the element dynamically in JavaScript, we can simply define it conditionally in the HTML code thanks to the pre-processor. Furthermore, the `fileInput`-element currently has a number of unnecessary CSS rules, since the element is *purposely* never made visibly.
Note that with these changes, the `fileInput`-element will now *always* have `display: none;` set. This shouldn't matter, since we can still trigger the `click`-event of the element just fine (via JavaScript) and this patch has been successfully tested in both Mozilla Firefox and Google Chrome.
The various functionality in `web/debugger.js` is currently *indirectly* added to the global scope, since that's how `var` works when it's used outside of any functions/closures.
Given how this functionality is being accessed/used, not just in the viewer but also in the API and textLayer, simply converting the entire file to a module isn't trivial[1]. However, we can at least export the `PDFBug`-part properly and then `import` that dynamically in the viewer.
Also, to improve the code a little bit, we're now *explicitly* exporting the necessary functionality globally.
According to MDN, see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import#browser_compatibility, all the browsers that we now support have dynamic `imports` implementations.
---
[1] We could probably pass around references to the necessary functionality, but given how this is being used I'm just not sure it's worth the effort. Also, adding *official* support for these viewer-specific debugging tools in the API feels both unnecessary and unfortunate.
At this point in time, after recent rounds of clean-up, the `webkit`-prefixed Fullscreen API is the only remaining *browser-specific* compatibility hack in the `web/`-folder JavaScript code.
The standard, and thus unprefixed, Fullscreen API has been supported for *over three years* in both Mozilla Firefox and Google Chrome. [According to MDN](https://developer.mozilla.org/en-US/docs/Web/API/Fullscreen_API#browser_compatibility), the unprefixed Fullscreen API has been available since:
- Mozilla Firefox 64, released on 2018-12-11; see https://wiki.mozilla.org/Release_Management/Calendar#Past_branch_dates
- Google Chrome 71, released on 2018-12-04; see https://en.wikipedia.org/wiki/Google_Chrome_version_history
Hence *only* Safari now requires using a prefixed Fullscreen API, and it's thus (significantly) lagging behind other browsers in this regard.
Considering that the default viewer is written *specifically* to be the UI for the Firefox PDF Viewer, and that we ask users to not just use it as-is[1], I think that we should only support the standard Fullscreen API now.
Furthermore, note also that the FAQ already lists Safari as "Mostly" supported; see https://github.com/mozilla/pdf.js/wiki/Frequently-Asked-Questions#faq-support
---
[1] Note e.g. http://mozilla.github.io/pdf.js/getting_started/#introduction
> The viewer is built on the display layer and is the UI for PDF viewer in Firefox and the other browser extensions within the project. It can be a good starting point for building your own viewer. *However, we do ask if you plan to embed the viewer in your own site, that it not just be an unmodified version. Please re-skin it or build upon it.*
- get original index in using a dichotomic seach instead of a linear one;
- normalize the text in using NFD;
- convert the query string into a RegExp;
- replace whitespaces in the query with \s+;
- handle hyphens at eol use to break a word;
- add some \s* around punctuation signs
This `disableCreateObjectURL` option was originally introduced all the way back in PR 4103 (eight years ago), in order to work-around `URL.createObjectURL()`-bugs specific to Internet Explorer.
In PR 8081 (five years ago) the `disableCreateObjectURL` option was extended to cover Google Chrome on iOS-devices as well, since that configuration apparently also suffered from `URL.createObjectURL()`-bugs.[1]
At this point in time, I thus think that it makes sense to re-evaluate if we should still keep the `disableCreateObjectURL` option.
- For Internet Explorer, support was explicitly removed in PDF.js version `2.7.570` which was released one year ago and all IE-specific compatibility code (and polyfills) have since been removed.
- For Google Chrome on iOS-devices, while we still "support" such configurations, it's *not* the focus of any development and platform-specific bugs are thus often closed as WONTFIX.
Note here that at this point in time, the `disableCreateObjectURL` option is *only* being used in the viewer and any `URL.createObjectURL()`-bugs browser/platform bugs will thus not affect the main PDF.js library. Furthermore, given where the `disableCreateObjectURL` option is being used in the viewer the basic functionality should also remain unaffected by these changes.[2]
Furthermore, it's also possible that the `URL.createObjectURL()`-bugs have been fixed in *browser* itself since PR 8081 was submitted.[3]
Obviously you could argue that this isn't a lot of code, w.r.t. number of lines, and you'd be technically correct. However, it does add additional complexity in a few different viewer components which thus add overhead when reading and working with this code.
Finally, assuming the `URL.createObjectURL()`-bugs are still present in Google Chrome on iOS-devices, I think that we should ask ourselves if it's reasonable for the PDF.js project (and its contributors) to keep attempting to support a configuration if the *browser* developers still haven't fixed these kind of bugs!?
---
[1] According to https://groups.google.com/a/chromium.org/forum/#!topic/chromium-html5/RKQ0ZJIj7c4, which is linked in PR 8081, that bug was mentioned/reported as early as the 2014 (eight years ago).
[2] Viewer functionality such as e.g. downloading and printing may be affected.
[3] I don't have access to any iOS-devices to test with.
So that Firefox doesn't switch to pixel mode for compat with other
browsers.
This should fix https://github.com/mozilla/pdf.js/issues/14476, in terms
of restoring the previous behavior.
We probably want to change the pixel-based scrolling code to not scroll
so much (the deltaMode stuff normalizes to +/-1 tick for each wheel
event, perhaps the pixel-based value should do the same).
*Please note:* This is a tentative patch, since I don't know if this is deemed important enough to fix.
The new event could be seen as a *supplement* to the existing "documentinit" and "documentloaded" events, but for the case when a PDF document fails to load.
To make the "documenterror" event generally useful, it'll include both the localized error message as well as the original reason for the error (when that exists).
As part of the changes/improvement in PR 14092, we're no longer using the `addLinkAttributes` directly in e.g. the AnnotationLayer-code.
Given that the helper function is now *only* used in the viewer, hence it no longer seems necessary to expose it through the official API.
*Please note:* It seems somewhat unlikely that third-party users were relying *directly* on the helper function, which is why it's not being exported as part of the viewer components. (If necessary, we can always change this later on.)
This structure contains *almost* exclusively references to DOM elements (and a couple of simple strings), rather than complete classes/functions. Hence the `eventBus`-option sticks out a fair bit, and I'd guess that it's *mostly* unused in e.g. third-party implementations.
Given that we, in multiple places, mention that the default viewer shouldn't be used as-is I really don't think that we need to keep this special `eventBus`-option around. Furthermore, nowadays it's also a lot easier to (safely) access the existing `EventBus`-instance in the viewer; see https://github.com/mozilla/pdf.js/wiki/Third-party-viewer-usage#initialization-promise which shows how to listen for the default viewer being initialized (and its `eventBus` thus being available).
This patch, first of all, removes circular dependencies in the TypeScript definitions. Secondly, it also moves `RenderingStates` into `web/ui_utils.js` to break another type-dependency and directly use the `XfaLayerBuilder` during XFA-printing.
Finally, note that this patch *slightly* reduces the size of the default viewer (e.g. in the `MOZCENTRAL` build) by not having to bundle code which is completely unused.
The size of the `web/ui_utils.js` file has increased over time, as more code has been added to (or moved into) that file. To reduce its size slightly, this patch moves the event-related functionality into a separate file.
In PR 14114 this was only added to the default viewer, which means that in the viewer components the user would need to *manually* implement /Lang handling. This was (obviously) a bad choice, since the viewer components already support e.g. structTrees by default; sorry about overlooking this!
To avoid having to make *two* `getMetadata` API-calls[1] very early during initialization, in the default viewer, the API will now cache its result. This will also come in handy elsewhere in the default viewer, e.g. by reducing parsing when opening the "document properties" dialog.
---
[1] This not only includes a round-trip to the worker-thread, but also having to re-parse the /Metadata-entry when it exists.
*This patch can be tested e.g. with the `poppler-85140-0.pdf` document from the test-suite.*
For some sufficiently corrupt documents the `getDocument` call will succeed, but fetching even the very first page fails. Currently we only print error messages (in the console) from the `{BaseViewer, PDFThumbnailViewer}.setDocument` methods, but don't actually provide these errors to allow the viewer to handle them properly.
In practice this means that the GENERIC viewer won't display the `errorWrapper`, and in the MOZCENTRAL viewer the *browser* loading indicator is never hidden (since we never unblock the "load" event).
*Please note:* These changes will primarily benefit longer documents, somewhat at the expense of e.g. one-page documents.
The existing `PDFDocumentProxy.getStats` function, which in the default viewer is called for each rendered page, requires a round-trip to the worker-thread in order to obtain the current document stats. In the default viewer, we currently make one such API-call for *every rendered* page.
This patch proposes replacing that method with a *synchronous* `PDFDocumentProxy.stats` getter instead, combined with re-factoring the worker-thread code by adding a `DocStats`-class to track Stream/Font-types and *only send* them to the main-thread *the first time* that a type is encountered.
Note that in practice most PDF documents only use a fairly limited number of Stream/Font-types, which means that in longer documents most of the `PDFDocumentProxy.getStats`-calls will return the same data.[1]
This re-factoring will obviously benefit longer document the most[2], and could actually be seen as a regression for one-page documents, since in practice there'll usually be a couple of "DocStats" messages sent during the parsing of the first page. However, if the user zooms/rotates the document (which causes re-rendering), note that even a one-page document would start to benefit from these changes.
Another benefit of having the data available/cached in the API is that unless the document stats change during parsing, repeated `PDFDocumentProxy.stats`-calls will return *the same identical* object.
This is something that we can easily take advantage of in the default viewer, by now *only* reporting "documentStats" telemetry[3] when the data actually have changed rather than once per rendered page (again beneficial in longer documents).
---
[1] Furthermore, the maximium number of `StreamType`/`FontType` are `10` respectively `12`, which means that regardless of the complexity and page count in a PDF document there'll never be more than twenty-two "DocStats" messages sent; see 41ac3f0c07/src/shared/util.js (L206-L232)
[2] One example is the `pdf.pdf` document in the test-suite, where rendering all of its 1310 pages only result in a total of seven "DocStats" messages being sent from the worker-thread.
[3] Reporting telemetry, in Firefox, includes using `JSON.stringify` on the data and then sending an event to the `PdfStreamConverter.jsm`-code.
In that code the event is handled and `JSON.parse` is used to retrieve the data, and in the "documentStats"-case we'll then iterate through the data to avoid double-reporting telemetry; see https://searchfox.org/mozilla-central/rev/8f4c180b87e52f3345ef8a3432d6e54bd1eb18dc/toolkit/components/pdfjs/content/PdfStreamConverter.jsm#515-549
Reporting telemetry, in Firefox, includes using `JSON.stringify` on the data and then sending an event to the `PdfStreamConverter.jsm`-code.
In that code the event is handled and `JSON.parse` is used to retrieve the data, and in the "pageInfo"-case we'll then proceed to ignore everything except *the first* such event; see https://searchfox.org/mozilla-central/rev/24fac1ad31fb9c6e9c4c767c6a7ff45d226078f3/toolkit/components/pdfjs/content/PdfStreamConverter.jsm#509-514
All-in-all, sending the "pageInfo" telemetry for each rendered page is thus unnecessary and this patch makes the viewer send it only *once* instead.
I missed this one spot in PR 12870, when converting the other cases in the "keydown" event handler. However, given that it only matters in PresentationMode and/or when "page-fit" zooming is enabled, this oversight shouldn't have had any user-observable impact (but we should fix it nonetheless).
Unfortunately there exist PDF documents where all pageLabels are empty strings, see e.g. http://www.cs.cornell.edu/~ragarwal/pubs/blk-switch.pdf (taken from an old issue), which result in the pageNumber-input being completely blank. That doesn't seem very helpful, and this patch simply extends the approach used to ignore pageLabels that are identical to standard page numbering.
*Please note:* This is a tentative patch, since I don't have the necessary a11y-software to actually test it.
To avoid having to add a new API-method just for a single string, I figured that adding the new property to the existing `documentInfo`-data (accessed via `PDFDocumentProxy.getMetadata` in the API) will hopefully be deemed acceptable.
Looking at the code, I do have to agree with the point made in issue 12731 about it being unexpected/unhelpful that the `PDFFindController.executeCommand`-method isn't directly usable with the "find"-event.
The reason for it being this way is, as so often, for historical reasons: The `executeCommand`-method was added (just) prior to the introduction of the `EventBus` in the viewer.
Obviously we cannot simply change the existing `PDFFindController.executeCommand`-method, since that'd be a breaking change in code which has existed for over five years.
Initially I figured that we could simply add a new method in `PDFFindController` that'd accept the state from the "find"-event, however after thinking about this and looking through the use-cases in the default viewer I settled on a slightly different approach: Let the `PDFFindController` just listen for the "find"-event (on the `EventBus`-instance) directly instead, which also removes one level of (unneeded) indirection during searching in the default viewer.
For GENERIC builds of the PDF.js library, the old `PDFFindController.executeCommand`-method is still available with a deprecation warning.
This implements a new Page scrolling mode, essentially bringing (and extending) the functionality from `PDFSinglePageViewer` into the regular `PDFViewer`-class. Compared to `PDFSinglePageViewer`, which as its name suggests will only display one page at a time, in the `PDFViewer`-implementation this new Page scrolling mode also support spreadModes properly (somewhat similar to e.g. Adobe Reader).
Given the size and scope of these changes, I've tried to focus on implementing the basic functionality. Hence there's room for further clean-up and/or improvements, including e.g. simplifying the CSS/JS related to PresentationMode and implementing easier page-switching with the mouse-wheel/arrow-keys.
Currently any AppOptions set using e.g. the "webviewerloaded" event listener can/will by default be overridden when the Preferences are read.
To avoid that happening the "disablePreferences"-option can be used, however unless it's been explicitly set all non-default AppOptions will be silently ignored. This patch thus attempts to improve the current situation somewhat, for third-party implementations, by logging a warning in the console when this happens.
Given the simplicity of this functionality, we can move it from the default viewer and into the `BaseViewer` class instead. This way, it's possible to support more scripting functionality in the standalone viewer components; please see PR 14038.
Please note that I purposely went with `increaseScale`/`decreaseScale`-method names, rather than using "zoom", to better match the existing `currentScale`/`currentScaleValue` getters/setters that's being used in the `BaseViewer` class.
Rather than forcing the "regular" `EventBus` to check and handle `isInAutomation` for every `dispatch` call, we can take advantage of subclassing instead.
Hence this PR introduces a new `AutomationEventBus` class, which extends `EventBus`, and is used by the default viewer when `isInAutomation === true`.
Originally the library/viewer didn't support forms, and the hiding of the Download-buttons (when new documents are opened) didn't really matter all that much. Hence the simplest solution, at the time, was to hide the Download-buttons since we use the URL as a fallback when downloading data in the GENERIC `DownloadManager`.
Nowadays we obviously want to support saving of forms in the GENERIC viewer, regardless of how the document was opened, which could thus *potentially* lead to the fallback download-URL being wrong.
In order to be able to show the Download-buttons unconditionally, this patch slightly re-factors the viewer to track the download-URL *separately* to prevent any issues there.
*Please note:* As mentioned in the issue, the ViewBookmark-buttons are specific to the initial URL when the viewer is first opened. Hence they (still) don't make sense when a new document has been opened, since it's then impossible to obtain a usable link to the *currently* active document.
Similar to other viewer components, e.g. the `PDFFindBar` and `PDFPresentationMode`, there's no need to create a `PDFHistory`-instance when it's not going to be used.
A lot of the code in this getter has existed ever since the initial PresentationMode-implementation was first added all the way back in PR 1938 (which is nine years ago now).
At this point in time however, there's now a simpler way detect if a browser supports the FullScreen API and we should thus be able to simplify this getter; please refer to https://developer.mozilla.org/en-US/docs/Web/API/Document/fullscreenEnabled#browser_compatibility
*This is a follow-up to PRs 13867 and 13899.*
This patch is tagged `api-minor` for the following reasons:
- It replaces the `renderInteractiveForms`/`includeAnnotationStorage`-options, in the `PDFPageProxy.render`-method, with the single `annotationMode`-option that controls which annotations are being rendered and how. Note that the old options were mutually exclusive, and setting both to `true` would result in undefined behaviour.
- For improved consistency in the API, the `annotationMode`-option will also work together with the `PDFPageProxy.getOperatorList`-method.
- It's now also possible to disable *all* annotation rendering in both the API and the Viewer, since the other changes meant that this could now be supported with a single added line on the worker-thread[1]; fixes 7282.
---
[1] Please note that in order to simplify the overall implementation, we'll purposely only support disabling of *all* annotations and that the option is being shared between the API and the Viewer. For any more "specialized" use-cases, where e.g. only some annotation-types are being rendered and/or the API and Viewer render different sets of annotations, that'll have to be handled in third-party implementations/forks of the PDF.js code-base.
The `loadAndEnablePDFBug` helper function, in `web/app.js`, can be simplified a little bit by making it `async`. Furthermore, given how `PDFBug` is being used, we can also (slightly) re-factor `PDFBug.init` such that the `PDFBug.enable`-call is done internally rather than having to handle that manually at the call-site.
(Finally, utilize `await` more in the `loadFakeWorker` helper function.)
This patch removes the only remaining closure in the `src/display/api.js` file, utilizing a similar approach as used in lots of other parts of the code-base, which results in a small decrease in the size of the *build* `pdf.js` file.
Given that `PDFWorker` is exposed through the *public* API, this complicates things somewhat since there's a couple of worker-related properties that really should stay *private*. Initially, while working on PR 13813, I believed that we'd need support for private (static) class fields in order to get rid of this closure, however I've managed to come up with what's hopefully deemed an acceptable work-around here.
Furthermore, some helper functions were simply moved into the `PDFWorker` class as static methods, thus simplifying the overall implementation (e.g. we don't need to manually cache the Promise in the `PDFWorker._setupFakeWorkerGlobal`-method).
Finally, as part of this re-factoring a number of missing JSDoc-comments were added which *together* with the removal of the closure significantly improves the `gulp jsdoc` output for the `PDFWorker` class.
*Please note:* This patch is tagged with `api-minor` since it deprecates `PDFWorker.getWorkerSrc()` in favor of the shorter `PDFWorker.workerSrc`, with the fallback limited to `GENERIC` builds.
Even though the code as-is *should* be safe, given that we're using an Object with a `null` prototype, it cannot hurt to change this to a Map to prevent any issues (since we're parsing unknown and potentially unsafe data).
Overall I also think that these changes improve the `parseQueryString` call-sites, since we now have a proper way of checking for the existence of a particular key (and don't have to use `in` which stringifies the keys in the Object).
This patch also changes the default, when no `value` exists, from `null` to an empty string since the use of `decodeURIComponent` currently can modify the value in a somewhat surprising way (at least to me).
Note how `decodeURIComponent(null) === "null"` which is unlikely to be what you actually want, whereas `decodeURIComponent("") === ""` which seems much more helpful.
Prior to PR 13042, when scripting wasn't really possible to use outside of the full viewer, the `enableScripting` option made sense.
However, at this point in time having to both pass in a `PDFScriptingManager`-instance *and* set the `enableScripting`-boolean when creating a `BaseViewer`-instance feels redundant and (mostly) annoying. Hence this patch, which removes the *separate* boolean and always enables scripting when `scriptingManager` is provided.
The relevant "viewer component" examples are also updated (with a comment), but in such a way that scripting support won't just break when used with the current PDF.js releases.
Given that we've over time been reducing the number of `compatibilityParams` in use, there's now few enough left that I think it makes sense to simply inline them directly in the `web/app_options.js` file.
Note that we recently inlined/removed the separate `src/display/api_compatibility.js` file, see PR 13525, and that it (in my opinion) thus makes sense to do the same in the `web/`-folder. This patch will also slightly reduce the size of *built* `web/viewer.js` file, which cannot hurt.
The PDF.js API has only ever supported accessing the original file ID, however the second one that (should) exist in *modified* documents have thus far been completely inaccessible through the API.
That seems like a simple oversight, caused e.g. by the viewer not needing it, since it really shouldn't hurt to provide API-users with the ability to check if a PDF document has been modified since its creation.[1]
Please refer to https://www.adobe.com/content/dam/acom/en/devnet/pdf/pdfs/PDF32000_2008.pdf#G13.2261661 for additional information.
For an example of how to update existing code to use the new API, please see the changes in the `web/app.js` file included in this patch.
*Please note:* While I'm not sure if we'll ever be able to remove the old `PDFDocumentProxy.fingerprint` getter, given that it's existed since "forever", that probably isn't a big deal given that it's now limited to only `GENERIC`-builds.
---
[1] Although this obviously depends on the PDF software following the specification, by updating the second file ID as intended.
Given that this property is only used with password protected documents, and is consequently document-specific rather than viewer-specific, ensure that `IPDFLinkService.externalLinkEnabled` is actually being reset by `PDFViewerApplication.close`.
To make things less confusing/inconsistent, remove the *undocumented* `externalLinkEnabled` property from the `PDFLinkService` constructor and force it to always be manually set when needed.
Reasons for the removal include:
- This functionality was always somewhat experimental and has never been enabled by default, partly because of worries about rendering bugs caused by e.g. bad/outdated graphics drivers.
- After the initial implementation, in PR 4286 (back in 2014), no additional functionality has been added to the WebGL implementation.
- The vast majority of all documents do not benefit from WebGL rendering, since only a couple of *specific* features are supported (e.g. some Soft Masks and Patterns).
- There is, and has always been, *zero* test-coverage for the WebGL implementation.
- Overall performance, in the PDF.js library, has improved since the experimental WebGL implementation was added.
Rather than shipping unused *and* untested code, it seems reasonable to simply remove the WebGL implementation for now; thanks to version control it's always possible to bring back the code should the need ever arise.
According to a decision by UX and PM, please see https://bugzilla.mozilla.org/show_bug.cgi?id=1705060#c2 (and implemented in https://bugzilla.mozilla.org/show_bug.cgi?id=1705327), we no longer show the notification-bar in Firefox; hence the special `PDFViewerApplication._delayedFallback` functionality should no longer be necessary.
Furthermore, note that at this point in time *most* of the features which used the `PDFViewerApplication._delayedFallback` functionality is now enabled by default; hence that provides even less reason to keep this code around and existing calls are thus converted to "regular" `PDFViewerApplication.fallback` calls.
According to a decision by UX and PM, please see https://bugzilla.mozilla.org/show_bug.cgi?id=1705060#c2, in Firefox we should first of all *not* display the notification-bar for signatures. Secondly, as can also be seen there, we shouldn't display the notification-bar *at all* and it's thus disabled in https://bugzilla.mozilla.org/show_bug.cgi?id=1705327.
If we purposely don't display a notification, for documents with signatures, in the *built in* Firefox PDF Viewer then it cannot be necessary in the GENERIC viewer either.
To simplify the overall implementation, given that it only applies to the GENERIC-viewer, this patch purposely re-uses the existing `errorWrapper`-functionality to display the message.
While that one is mostly intended for actual *errors*, by re-using it here we considerably reduce the amount of code/complexity necessary for supporting this new warning. It's obviously possible to re-factor/improve this later on, but the patch should do just fine here since it'll indeed inform users (of the GENERIC-viewer) about unverified signatures.
Finally this patch also tweaks the background-color of the `errorWrapper`, making it 20 percent lighter respectively darker (depending on the theme) to make it "stand out" a little bit *less*.[1] While it may perhaps be useful to re-style/re-factor the `errorWrapper`, this patch probably isn't the right place for doing that.
---
[1] Note how in the MOZCENTRAL-viewer, which instead uses the browser notification-bar, we're purposely using a neutral colour to not draw too much attention to the notification-bar.
- but don't validate them for now;
- Firefox will display a bar to warn that the signature validation is not supported (see https://bugzilla.mozilla.org/show_bug.cgi?id=854315)
- almost all (all ?) pdf readers display signatures;
- validation is done in edge but for now it's behind a pref.
*This patch fixes some technical debt in the viewer.*
Given that most API methods are (purposely) asynchronous, there's always a risk that the viewer could have been `close`d before the requested data arrives.
Lately we've started to check this case before using the data, to prevent errors and/or inconsistent state, however the outline/attachments/layers fetching and rendering is old enough that it pre-dates those checks.
Note how we purposely don't expose the `AnnotationStorage`-class directly in the official API (see `src/pdf.js`), since trying to use *multiple* ones simultaneously doesn't really make sense (e.g. in the viewer).
Instead we lazily initialize, and cache, just *one* instance via `PDFDocumentProxy.annotationStorage` which should thus be available internally in the API itself without having to be manually passed to various methods.
To support these changes, the `AnnotationStorage`-instance initialization is moved into the `WorkerTransport`-class to allow both `PDFDocumentProxy` and `PDFPageProxy` to access it.
This patch implements the following simplifications:
- Remove the `annotationStorage`-parameter from `PDFDocumentProxy.saveDocument`, since it's already available internally.
Furthermore, while it's currently possible to call that method without an `AnnotationStorage`-instance, that really does *not* make any sense at all. In this case you're effectively reducing `PDFDocumentProxy.saveDocument` to a "regular" `PDFDocumentProxy.getData` call, but with *a lot* more overhead, which was obviously not the intention of the `PDFDocumentProxy.saveDocument`-method.
- Try to discourage third-party users from calling `PDFDocumentProxy.saveDocument` unconditionally, as a replacement for `PDFDocumentProxy.getData` (note the previous point).
- Replace the `annotationStorage`-parameter, in `PDFPageProxy.render`, with a boolean `includeAnnotationStorage`-parameter which simply indicates if the (internally available) `AnnotationStorage`-instance should be used during rendering (e.g. for printing).
- By removing the need to *manually* provide `annotationStorage`-parameters to various API-methods, using the API should become simpler (e.g. for third-parties) since you no longer need to worry about manually fetching and passing around this data.
As discussed in the issue, this is a small/simple patch that should help to prevent *outright* data loss in forms when a new document is opened in the GENERIC viewer.
While the implementation is perhaps a bit "simplistic", it does seem to work and should be fine given that this is an edge-case only relevant for the GENERIC viewer.
In the next patch we'll need to be able to actually wait for saving to complete, hence it's necessary to slightly re-factor the `save`-method.
As part of these changes, we can reduce some duplication in the `save`-method and slightly improve the overall code. For consistency, the `download`-method is updated similarily to improve the code (this functionality is *very* old, even pre-dating the introduction of Promises in the code-base).
As mentioned in the JSDoc comment, this should not be used unless you know what you're doing, since it will lead to increased memory usage. However, in some situations (e.g. SVG-rendering), we still want to be able to run general clean-up on both the main/worker-thread while keeping loaded fonts attached to the DOM.[1]
As part of these changes, `WorkerTransport.startCleanup` is converted to an async method and we'll also skip clean-up when destruction has started (since it's redundant).
---
[1] The SVG-rendering mode is obviously not officially supported, since it's both rather incomplete and inherently slower. However with recent changes, whereby we cache repeated images on the document rather than the page level, memory usage can be *a lot* worse than before if we never attempt to release e.g. cached image-data when the viewer is in SVG-rendering mode.
Given that *all* data has been loaded on the main-thread, and then transferred to the worker-thread, ever since PR 8617 (almost four years ago) it should no longer be necessary to keep this special-case around.
Given that the `webViewerOpenFileViaURL` helper function is being defined in *all* builds anyway, the current pre-processor usage doesn't really improve readability in my opinion.
The rotation handling that's currently living in `PDFViewerApplication` is *very* old, and pre-dates the introduction of the viewer components by years.
As can be seen in the `BaseViewer.pagesRotation` setter, we're not actually normalizing the rotation as intended and instead rely on the caller to handle that correctly. This is first of all inconsistent, given how other setters are implemented, and secondly it could also lead to the rotation being set to a value outside of the `[0, 360)`-range.
Finally, for improved consistency the rotation handling in `PageViewport` is updated similarly. Please note that this case, it's *not* changing the pre-existing logic.
Given that the `enableXfa` parameter must to be passed to the API/Worker, and thus included in the `getDocument` call, it's not necessary to include it when initializing the `PDFViewer`-instance used in the default viewer. (Also, in `AppOptions`, the parameter is clearly marked with `OptionKind.API`.)
Furthermore, we probably don't want to display the fallback bar (in Firefox) for XFA documents when `enableXfa = true` is set.
- add an option to enable XFA rendering if any;
- for now, let the canvas layer: it could be useful to implement XFAF forms (embedded pdf in xml stream for the background and xfa form for the foreground);
- ui elements in template DOM are pretty close to their html counterpart so we generate a fake html DOM from template one:
- it makes easier to translate template properties to html ones;
- it makes faster the creation of the html element in the main thread.
It seems reasonable to place this alongside the *similar* `getFilenameFromUrl` helper function. This way, with the changes in the next patch, we also avoid having to expose the `isDataScheme` function in the API itself and we instead expose `getPdfFilenameFromUrl` in the API (which feels overall more appropriate).
The *main* purpose of this patch is to allow scripting to be used together with the viewer components, note the updated "simpleviewer"/"singlepageviewer" examples, in addition to the full default viewer.
Given how the scripting functionality is currently implemented in the default viewer, trying to re-use this with the standalone viewer components would be *very* hard and ideally you'd want it to work out-of-the-box.
For an initial implementation, in the default viewer, of the scripting functionality it probably made sense to simply dump all of the code in the `app.js` file, however that cannot be used with the viewer components.
To address this, the functionality is moved into a new `PDFScriptingManager` class which can thus be handled in the same way as all other viewer components (and e.g. be passed to the `BaseViewer`-implementations).
Obviously the scripting functionality needs quite a lot of data, during its initialization, and for the default viewer we want to maintain the current way of doing the lookups since that helps avoid a number of redundant API-calls.
To that end, the `PDFScriptingManager` implementation accepts (optional) factories/functions such that we can maintain the current behaviour for the default viewer. For the viewer components specifically, fallback code-paths are provided to ensure that scripting will "just work"[1].
Besides moving the viewer handling of the scripting code to its own file/class, this patch also takes the opportunity to re-factor the functionality into a number of helper methods to improve overall readability[2].
Note that it's definitely possible that the `PDFScriptingManager` class could be improved even further (e.g. for general re-use), since it's still heavily tailored to the default viewer use-case, however I believe that this patch is still a good step forward overall.
---
[1] Obviously *all* the relevant document properties might not be available in the viewer components use-case (e.g. the various URLs), but most things should work just fine.
[2] The old `PDFViewerApplication._initializeJavaScript` method, where everything was simply inlined, have over time (in my opinion) become quite large and somewhat difficult to *easily* reason about.
These changes will be necessary for the next patch, since we don't want to accidentally pull in the entire default viewer in the standalone viewer components.
Rather than having to spell out the English fallback strings at *every* single `IL10n.get` call-site throughout the viewer, we can simplify things by collecting them in *one* central spot.
This provides a much better overview of the fallback l10n strings used, which makes future changes easier and ensures that fallback strings occuring in multiple places cannot accidentally get out of sync.
Furthermore, by making the `fallback` parameter of the `IL10n.get` method *optional*[1] many of the call-sites (and their surrounding code) become a lot less verbose.
---
[1] It's obviously still possible to pass in a fallback string, it's just not required.
The only reason, as far as I can tell, for parsing the Metadata on the main-thread is how it was originally implemented. When Metadata support was first implemented, it utilized the [`DOMParser`](https://developer.mozilla.org/en-US/docs/Web/API/DOMParser) which isn't available in workers.
Today, with the custom XML-parser being used, that's no longer an issue and it seems reasonable to move the Metadata parsing to the worker-thread[1], since that's where all parsing should happen (for performance reasons).
Based on these changes, we'll be able to reduce the now unnecessary duplication of the XML-parser (and related code) in both of the *built* `pdf.js`/`pdf.worker.js` files.
Finally, this patch changes the `_repair` method to use "Array + join" rather than string concatenation.
---
[1] This needed the previous patch, to enable sending of `Map`s between threads with workers disabled.
*This is somewhat similar to PR 12931.*
For PDF documents where fonts are completely missing in the /Resources dictionaries, there's basically no "correct" way of rendering the document.
Hence it's very unlikely that another PDF viewer will do a better job than PDF.js in these cases, and consequently it seems highly questionable if the fallback bar really helps here.
Given that these event listeners should essentially never be needed, but are included simply to avoid breakage in edge-cases, it can't hurt to make this code slightly less verbose.
Given that these HTML elements are not being used at all in `MOZCENTRAL`-builds, note the preprocessor check in `PDFViewerApplication._otherError`, we obviously don't need the HTML code either.
Some of the localization strings (e.g. "loading_error") are repeated multiple times throughout the `web/app.js` file, which means that we need to duplicate the fallback strings as well. Furthermore, the signature of the `IL10n.get` method makes the call-sites quite verbose.
By adding a new helper method, in `PDFViewerApplication`, we're able to gather the localization fallback strings in one central spot in `web/app.js` and also make the lookup of the error/warning messages more compact.
This code is *very* old and it even predates the existence of arrow functions. Hence we can now reduce the overall verbosity by not having to explicitly spell out `PDFViewerApplication` everywhere.
This feature was Firefox-specific, and it's now been removed from the HTML specification and it's disabled by default starting with Firefox 85. Hence it seems completely unnecessary to keep this code in the default viewer.
Please refer to https://groups.google.com/g/mozilla.dev.platform/c/tc11BCenm2c and the resources that it links to.
Given that we don't focus the viewer *itself* (among other things) when the viewer is embedded, I suppose that it makes some sense to not focus the `PasswordPrompt` input-field either on load.
In order to improve the overall UX here, if an *incorrect* password was provided we'll still focus the input-field.
Fixes 12951 (assuming we care to do so, of course).
With PR 10539, we'll now always attempt to fallback to the PDF.js built-in font renderer for fonts that fail to load (i.e. are rejected by the sanitizer). Generally speaking, these errors are the result of insufficient validation in the PDF.js font code, however in almost all cases we've seen thus far our built-in font renderer manages just fine.
However, we still trigger the `onUnsupportedFeature` reporting, which in Firefox causes the fallback bar to be displayed. Given that, in a majority of cases[1], things look fine it seems unfortunate to bother the user with the fallback bar here.
Note that even though we no longer show the fallback bar in this case, we still report telemetry as before.
---
[1] The only *known* case where things aren't fine with the built-in font renderer is issue 10232, however that document is sufficiently broken that there's a couple of other things that will trigger the fallback bar.
- For wrapped scrolling, we unfortunately need to do a fair bit of parsing of the *current* page layout. Compared to e.g. the spread-modes, where we can easily tell how the pages are laid out, with wrapped scrolling we cannot tell without actually checking. In particular documents with varying page sizes require some care, since we need to check all pages on the "row" of the current page are visible and that there aren't any "holes" present. Otherwise, in the general case, there's a risk that we'd skip over pages if we'd simply always advance to the previous/next "row" in wrapped scrolling.
- For horizontal scrolling, this patch simply maintains the current behaviour of advancing *one* page at a time. The reason for this is to prevent inconsistent behaviour for the next and previous cases, since those cannot be handled identically. For the next-case, it'd obviously be simple to advance to the first not completely visible page. However for the previous-case, we'd only be able to go back *one* page since it's not possible to (easily) determine the page layout of non-visible pages (documents with varying page sizes being a particular issue).
- For vertical scrolling, this patch maintains the current behaviour by default. When spread-modes are being used, we'll now attempt to advance to the next *spread*, rather than just the next page, whenever possible. To prevent skipping over a page, this two-page advance will only apply when both pages of the current spread are visible (to avoid breaking documents with varying page sizes) and when the second page in the current spread is fully visible *horizontally* (to handle larger zoom values).
In order to reduce the performance impact of these changes, note that the previous/next-functionality will only call `getVisibleElements` for the scroll/spread-modes where that's necessary and that "normal" vertical scrolling is thus unaffected by these changes.
To support these changes, the `getVisibleElements` helper function will now also include the `widthPercent` in addition to the existing `percent` property.
The `PDFViewer._updateHelper` method is changed slightly w.r.t. updating the `currentPageNumber` for the non-vertical/spread modes, i.e. won't affect "normal" vertical scrolling, since that helped simplify the overall calculation of the page advance.
Finally, these new `BaseViewer` methods also allow (some) simplification of previous/next-page functionality in various viewer components.
*Please note:* There's one thing that this patch does not attempt to change, namely disabling of the previous/next toolbarButtons respectively the firstPage/lastPage secondaryToolbarButtons. The reason for this is that doing so would add quite a bit of complexity in general, and if for some reason `BaseViewer._getPageAdvance` would get things wrong we could end up incorrectly disabling the buttons. Hence it seemed overall safer to *not* touch this, and accept that the buttons won't be `disabled` despite in some edge-cases no further scrolling being possible.
Note first of all how the `PDFDocumentProxy.getJSActions` method in the API caches the result, which makes repeated lookups cheap enough to not really be an issue.
Secondly, with the previous patch, we're now only dispatching "pageopen"/"pageclose"-events when there's actually a sandbox that listens for them.
All-in-all, with these changes we can thus simplify the default-viewer "pageopen"-event handler a fair bit.
The "pageopen"/"pageclose"-events are only necessary if, and only if, there's actually a sandbox to dispatch the events in. Hence we shouldn't dispatch those events unconditionally, as soon as `enableScripting` is set, but rather initialize that functionality only when needed.
Furthermore, in `web/app.js`, there's currently a bug since we're attempting to *manually* simulate a "pageopen"-event for a page that may not actually have been rendered at the time. With the modified `BaseViewer.initializeScriptingEvents` method, we'll now dispatch a correct "pageopen"-event here.
There's built-in ESLint rule, see `sort-imports`, to ensure that all `import`-statements are sorted alphabetically, since that often helps with readability.
Unfortunately there's no corresponding rule to sort `export`-statements alphabetically, however there's an ESLint plugin which does this; please see https://www.npmjs.com/package/eslint-plugin-sort-exports
The only downside here is that it's not automatically fixable, but the re-ordering is a one-time "cost" and the plugin will help maintain a *consistent* ordering of `export`-statements in the future.
*Note:* To reduce the possibility of introducing any errors here, the re-ordering was done by simply selecting the relevant lines and then using the built-in sort-functionality of my editor.
This implementation is inspired by the behaviour in (recent versions of) Adobe Reader, since it leads to reasonably simple and straightforward code as far as I'm concerned.
*Specifically:* We'll only consider *one* destination per page when finding/highlighting the current outline item, which is similar to e.g. Adobe Reader, and we choose the *first* outline item at the *lowest* level of the outline tree.
Given that this functionality requires not only parsing of the `outline`, but looking up *all* of the destinations in the document, this feature can when initialized have a non-trivial performance overhead for larger PDF documents.
In an attempt to reduce the performance impact, the following steps are taken here:
- The "find current outline item"-functionality will only be enabled once *one* page has rendered and *all* the pages have been loaded[1], to prevent it interfering with data regular fetching/parsing early on during document loading and viewer initialization.
- With the exception of a couple of small and simple `eventBus`-listeners, in `PDFOutlineViewer`, this new functionality is initialized *lazily* the first time that the user clicks on the `currentOutlineItem`-button.
- The entire "find current outline item"-functionality is disabled when `disableAutoFetch = true` is set, since it can easily lead to the setting becoming essentially pointless[2] by triggering *a lot* of data fetching from a relatively minor viewer-feature.
- Fetch the destinations *individually*, since that's generally more efficient than using `PDFDocumentProxy.getDestinations` to fetch them all at once. Despite making the overall parsing code *more* asynchronous, and leading to a lot more main/worker-thread message passing, in practice this seems faster for larger documents.
Finally, we'll now always highlight an outline item that the user manually clicked on, since only highlighting when the new "find current outline item"-functionality is used seemed inconsistent.
---
[1] Keep in mind that the `outline` itself already isn't fetched/parsed until at least *one* page has been rendered in the viewer.
[2] And also quite slow, since it can take a fair amount of time to fetch all of the necessary `destinations` data when `disableAutoFetch = true` is set.
Ensure that `PDFViewerApplication._contentLength` is always updated with the *correct* length, as returned by `PDFDocumentProxy.getDownloadInfo`, and only let the `PDFViewerApplication._initializeMetadata` method overwrite if it's not already been set.
Finally, in `PDFViewerApplication._initializeJavaScript`, the fallback `_contentLength` handling is now moved to just after the fallback `documentInfo` handling, such that all the fallback code is in one place within the method.
Note how the `onerror` functionality is not being used in the GENERIC `DownloadManager`, since we have no way of knowing if downloading succeeded.
Hence this functionality is only *possibly* useful in MOZCENTRAL builds, however as outlined in the existing comments it's unlikely to be helpful in practice. Generally speaking, if downloading failed once in [`PdfStreamConverter.jsm`](https://searchfox.org/mozilla-central/rev/809ac3660845fef6faf18ec210232fdadc0f1ad9/toolkit/components/pdfjs/content/PdfStreamConverter.jsm#294-406) it seems very likely that it would fail again; all-in-all I'm thus suggesting that we just remove the `onerror` functionality altogether here.
Currently this code is duplicated no less than three times in the `web/app.js` file, and by introducing a helper method we can avoid unnecessary repetition.
This method currently accepts a callback-function, which does feel a bit old fashioned now. At the time that this code was introduced, native Promises didn't exist yet and there's a custom Promise-implementation used instead.
However, today with Promises and async/await being used *a lot* it seems reasonable to change `DefaultExternalServices.fallback` to an `async` method instead such that the callback-function can be removed.
This follows the same principle as the `once` option that exists in the native `addEventListener` method, and will thus automatically remove an `EventBus` listener when it's invoked; see https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener#Parameters
Finally, this patch also tweaks some the existing `EventBus`-code to use modern features such as optional chaining and logical assignment operators.
Given that we already have a `PresentationModeState`-enumeration, we should use that with the "presentationmodechanged" event rather than including separate properties. Note that this new behaviour, of including an enumeration-value in the event, is consistent with lots of other existing viewer-events.
To hopefully avoid issues in custom implementations of the default viewer, any attempt to access the removed properties will now throw.
Similar to e.g. the "locale" option, this in *only* done for those build-targets where the "sandboxBundleSrc" is actually defined.
With these changes we can remove an `AppOptions` dependency from the `web/generic_scripting.js` file, thus limiting *direct* `AppOptions` usage in the default viewer files.
Given that the `dispatchEventInSandbox` method (on the scripting-classes) is asynchronous, there's a very real risk that the events won't be dispatched/handled until *after* their associated functionality has actually run (with the "Will..." events being particularily susceptible to this issue).
To reduce the likelihood of that happening, we can simply `await` the `dispatchEventInSandbox` calls as necessary. A couple of methods are now marked as `async` to support these changes, however that shouldn't be a problem as far as I can tell.
*Please note:* Given that the browser "beforeprint"/"afterprint" events are *synchronous*, we unfortunately cannot await the `WillPrint`/`DidPrint` event dispatching. To fix this properly the web-platform would need support for asynchronous printing, and we'll thus have to hope that things work correctly anyway.
Note that currently the `DidSave` event is not *guaranteed* to actually be dispatched if there's any errors during saving, which is easily fixed by simply moving it to occur in the `finally`-handler in `PDFViewerApplication.save` method.
For the `WillPrint`/`DidPrint` events, things are unfortunately more complicated. Currently these events will *only* be dispatched iff the printing request comes from within the viewer itself (e.g. by the user clicking on the "Print" toolbar button), however printing can be triggered in a few additional ways:
- In the GENERIC viewer:
- By the <kbd>Ctrl</kbd>+<kbd>P</kbd> keyboard shortcut.
- In the MOZCENTRAL viewer, i.e. the Firefox built-in viewer:
- By the <kbd>Ctrl</kbd>+<kbd>P</kbd> keyboard shortcut.
- By the "Print" item, as found in either the Firefox "Hamburger menu" or in the browser-window menu.
In either of the cases described above, no `WillPrint`/`DidPrint` events will be dispatched. In order to *guarantee* that things work in the general case, we thus have to move the `dispatchEventInSandbox` calls to the "beforeprint"/"afterprint" event handlers instead.
Rather than calling `getJavaScript` in the API and then ignoring the result, when "enableScripting" is set, it should be more efficient/faster to simply skip it altogether instead.
Finally, the `setTimeout` call at the end of `PDFViewerApplication._initializeAutoPrint` is removed, since it doesn't seem necessary any more as far as I can tell.[1]
Note that when this functionality was originally added, back in PR 2839, it seems that `pagesPromise` simply waited for the `getPage` calls of *all* pages to resolve. Today, on the other hand, the viewer fetches *and* renders the first page *before* doing the remaining `getPage` calls, and only afterwards is `pagesPromise` resolved. Hence it's not really clear why we now need to delay printing even further with a `setTimeout` call.
---
[1] The patch was tested with the following documents: https://github.com/mozilla/pdf.js/blob/master/test/pdfs/bug1001080.pdf and https://github.com/mozilla/pdf.js/blob/master/test/pdfs/issue6106.pdf
These callbacks should not be necessary *before* the document has been initialized. Furthermore, move the functionality to a new helper-method since `PDFViewerApplication.load` is already quite large.
Given that this relies on accessing properties on the `PDFDocumentProxy`-instance, it seems more appropriate for this code to live in `PDFViewerApplication`.
It seems that the timeout is way too short in practice, since this new integration-test failed *intermittently* already in PR 12702 (which is where the test was added).
The ideal solution here would be to simply await an event, dispatched by the viewer, however that unfortunately doesn't appear to be supported by Puppeteer.
Instead, the solution implemented here is to add a new method in `PDFViewerApplication` which Puppeteer can query to check if the scripting/sandbox has been fully initialized.
There's really no point, as far as I can tell, to attempt to dispatch an event in a non-existent sandbox. Generally speaking, even trying to do this *could* possibly even lead to errors in some cases.
Furthermore, utilize optional chaining to simplify some `dispatchEventInSandbox` calls throughout the viewer.
Finally, replace superfluous `return` statements with `break` in the switch-statement in the `updateFromSandbox` event-handler.
For DOM events all event names are lower-case, and the newly added PDF.js scripting-events thus "stick out" quite a bit. Even more so, considering that our internal `eventBus`-events follow the same naming convention.
Hence this patch, which changes the "updateFromSandbox"/"dispatchEventInSandbox" events to be lower-case instead.
Furthermore, using DOM events for communication *within* the PDF.js code itself (i.e. between code in `web/app.js` and `src/display/annotation_layer.js/`) feels *really* out of place.
That's exactly the reason that we have the `EventBus` abstraction, since it allowed us to remove prior use of DOM events, and this patch thus re-factors the code to make use of the `EventBus` instead for scripting-related events.
Obviously for events targeting a *specific element* using DOM events is still fine, but the "updatefromsandbox"/"dispatcheventinsandbox" ones should be using the `EventBus` internally.
*Drive-by change:* Use the `BaseViewer.currentScaleValue` setter unconditionally in `PDFViewerApplication._initializeJavaScript`, since it accepts either a string or a number.
- Actually remove the `isDown` property when destroying the scripting-instance.
- Mark all `mouseState` usage as "private" in the various classes.
- Ensure that the `AnnotationLayer` actually treats the parameter as properly *optional*, the same way that the viewer components do.
- For now remove the `mouseState` parameter from the `PDFPageView` class, and keep it only on the `BaseViewer`, since it's questionable if all of the scripting-functionality will work all that well without e.g. a full `BaseViewer`.
- Append the `mouseState` to the JSDoc for the `AnnotationElement` class, and just move its definition into the base-`AnnotationElement` class.
* the goal is to execute actions like Open or OpenAction
* can be tested with issue6106.pdf (auto-print)
* once #12701 is merged, we can add page actions
* move set/clear|Timeout/Interval and crackURL code in pdf.js
* remove the "backdoor" in the proxy (used to dispatch event) and so return the dispatch function in the initializer
* remove listeners if an error occured during sandbox initialization
* add support for alert and prompt in the sandbox
* add a function to eval in the global scope
Given that the GENERIC default viewer supports opening more than one document, and that a unique scripting-instance is now used for each document, the changes made in this patch seem appropriate.
Since the `close` method has become quite large, this small re-factoring shouldn't hurt (and may also be useful with future changes to the `_initializeJavaScript` method).
I was actually quite surprised to find that, despite the various `scripting`-getters implementing `destroySandbox` methods, there were no attempts at actually cleaning-up either the "sandbox" or removing the globally registered event listeners.
This patch also changes the method to skip *all* data fetching when "enableScripting" isn't active. Finally, simplifies some event-data accesses in the "updateFromSandbox" listener.
Another possible option here could be to use the `contentLength`, when it exists, and then using e.g. a custom event to always update the "filesize" in the sandbox "after the fact" with the result of the `getDownloadInfo`-call.
We can easily avoid unnecessary API-calls here, since most of the time the `metadata` will already be available here. In the *rare* case that it's not available, we can simply wait for the existing `getMetadata`-call to resolve.
This will be useful in the following patch, and note that there's also an old issue (see 5765) which asked for such an event. However, given that the use-case wasn't *clearly* specified, and that we didn't have an internal use for it at the time it wasn't implemented.
Also, ensure that all of the metadata-related properties are actually reset when the document is closed.
Given that we already include the "Content-Disposition"-header filename, when it exists, it shouldn't hurt to also include the information from the "Content-Length"-header.
For PDF documents opened via a URL, which should be a very common way for the PDF.js library to be used, this will[1] thus provide a way of getting the PDF filesize without having to wait for the `getDownloadInfo`-promise to resolve[2].
With these API improvements, we can also simplify the filesize handling in the `PDFDocumentProperties` class.
---
[1] Assuming that the server is correctly configured, of course.
[2] Since that's not *guaranteed* to happen in general, with e.g. `disableAutoFetch = true` set.
Given that it's generally faster to call *one* function and have it loop through an object, rather than looping through an object and calling a function for every iteration, this patch will reduce the total time spent in `PDFViewerApplication._readPreferences` ever so slightly.
Also, over time we've been adding more and more preferences, rather than removing them, so using the new `AppOptions.setAll` method should be generally beneficial as well.
While the effect of these changes is quite small, it does reduces the time it takes for the preferences to be fully initialized. Given the amount of asynchronous code during viewer initialization, every bit of time that we can save should thus help.
Especially considering the recently added `viewerCssTheme` preference, which needs to be read very early to reduce the risk of the viewer UI "flashing" visibly as the theme changes, I figured that a couple of small patches reducing the time spend reading preferences cannot hurt.
Given that only two debugging hash parameters (i.e. `disableWorker` and `pdfBug`) will make this method asynchronous, we can avoid what's most of the time is an unnecessary `Promise.all` invocation.
While this does work pretty well in my quick testing, it's *very much* a hack since as far as I can tell there's no support in the CSS specification for using e.g. a CSS variable to override a `@media (prefers-color-scheme: dark) {...}` block.
The solution implemented here is thus to *edit* the viewer CSS, by either removing the entire `@media ...` block in light-mode or by ensuring that its rules become *unconditionally* applied in dark-mode.
To simplify the overall implementation, since all of this does seem like somewhat of an edge-case, the `viewerCssTheme` preference will *only* be read during viewer initialization. (Similar to many other existing preferences, a reload is thus required when changing it.)
* When no actions then set it to null instead of empty object
* Even if a field has no actions, it needs to listen to events from the sandbox in order to be updated if an action changes something in it.
Note that a number of these cases are covered by existing unit-tests, and a few others only matter for the development/build scripts.
Furthermore, I've also tried to the best of my ability to test each case *manually* to hopefully further reduce the likelihood of this patch introducing any bugs.
Please find additional details about the ESLint rule at https://eslint.org/docs/rules/no-useless-escape
This patch addresses a review comment, which pointed out that we should *also* handle the pageNumber-input, from PR 12493.
Given that a user *manually* changing pages using the pageNumber-input, on the toolbar, could be regarded as a pretty strong indication of user-intent w.r.t. navigation in the document, hence I suppose that updating the browser history in this case as well probably won't hurt.
- Return early in `PDFViewerApplication._initializeJavaScript` for PDF documents without any `fieldObjects`, which is the vast majority of all documents, to prevent errors when trying to parse a non-existent object.
- Similar to the other `PDFViewerApplication._initialize*` methods, ignore the `fieldObjects` if the document was closed before the data resolved.
- Fix the JSDoc comment for the `generateRandomStringForSandbox` helper function, since there's currently a bit too much copy-and-paste going on :-)
- Change `FirefoxScripting` to a class with static methods, which is consistent with the surrounding code in `web/firefoxcom.js`.
The `debugger`-statement would only, potentially, make sense during development and we thus want to prevent it from being accidentally included when landing code.
The `alert`, `confirm`, and `prompt` functions should generally be avoided, with the few intended cases manually allowed.
Please find additional details about the ESLint rules at:
- https://eslint.org/docs/rules/no-debugger
- https://eslint.org/docs/rules/no-alert
This adds a new `PDFViewerApplication.triggerPrinting` method, which takes care of checking that printing is actually supported before calling `window.print`, to remove the need to duplicate that code in multiple places.
Also, removes the `PDFViewerApplication.printing` getter since it's not really necessary any more.
For now we need to use a Babel-plugin, since part of our build system doesn't support this fully (e.g. Babel-loader, Webpack 4.x, and SystemJS).
While the `?.` operator will thus always be transpiled by Babel, even in modern builds, simply supporting it for development purposes seems like a step in the right direction.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining
Given how those are used, there *should* not be any situation in which e.g. `undefined` is ever returned. However, actually checking that the pageView/thumbnail is defined cannot hurt.
Also, re-factor `webViewerPageRendered` slightly since the `pageView` is no longer unconditionally necessary after the previous patches; note in particular that the thumbnails will only be updated when the sidebar *and* the thumbnailView is visible.
Finally, fixes a bug in `webViewerPageChanging` whereby an empty string would not be treated as a valid pageLabel and instead be replaced by `null`.
Given that the default viewer only uses the "page stats" when debugging is enabled, it seems much simpler and more straightforward to simply query the API *directly* when this information is actually required. That way, there's a bit less information that needs to be stored/updated on each `PDFPageView`-instance.
Finally, since the `EventBus` now exists, we no longer need to handle the "page stats"-case in the regular listeners in `web/app.js`, but can instead add special "page stats"-listeners only when debugging is enabled.
The way that rendering errors are handled in `PDFPageView` is *very* old, and predates e.g. the introduction of the `EventBus` by several years.
Hence we should be able to simplify things a bit here, by including the Error (when it exists) in the "pagerendered" event and thus avoid having to reach into `PDFPageView` for it.
This patch purposely starts small, by removing IE-specific code from various JS/CSS files in the `web/` folder.
There's obviously lots of potential for additional clean-up, especially the removal of no longer necessary polyfills in `src/shared/compatibility.js`, however that will require some care considering that certain polyfills may also be necessary for e.g. Node.js or the Chromium-extension as well.
Generally speaking, once we start removing polyfills it's probably a good idea to consult the compatibility information on https://developer.mozilla.org/ and also https://caniuse.com/ first. (Deciding on the lowest supported Chromium version, for the extension, would also seem like a good idea.)
All of the core/display functionality needed to support this already exists, we simply need to handle these named actions in the viewer and the buttons will "just" work.
Unfortunately there's not really any good way of testing this, but given the size and scope of the patch that's hopefully OK.
*Besides, obviously, adding viewer support:* This patch attempts to improve the general API for Optional Content Groups slightly, by adding a couple of new methods for interacting with the (more complex) data structures of `OptionalContentConfig`-instances. (Thus allowing us to mark some of the data as "private", given that it probably shouldn't be manipulated directly.)
By utilizing not just the "raw" Optional Content Groups, but the data from the `/Order` array when available, we can thus display the Layers in a proper tree-structure with collapsible headings for PDF documents that utilizes that feature.
Note that it's possible to reset all Optional Content Groups to their default visibility state, simply by double-clicking on the Layers-button in the sidebar.
(Currently that's indicated in the Layers-button tooltip, which is obviously easy to overlook, however it's probably the best we can do for now without adding more buttons, or even a dropdown-toolbar, to the sidebar.)
Also, the current Layers-button icons are a little rough around the edges, quite literally, but given that the viewer will soon have its UI modernized anyway they hopefully suffice in the meantime.
To give users *full* control of the visibility of the various Optional Content Groups, even those which according to the `/Order` array should not (by default) be toggleable in the UI, this patch will place those under a *custom* heading which:
- Is collapsed by default, and placed at the bottom of the Layers-tree, to be a bit less obtrusive.
- Uses a slightly different formatting, compared to the "regular" headings.
- Is localizable.
Finally, note that the thumbnails are *purposely* always rendered with all Optional Content Groups at their default visibility state, since that seems the most useful and it's also consistent with other viewers.
To ensure that this works as intended, we'll thus disable the `PDFThumbnailView.setImage` functionality when the Optional Content Groups have been changed in the viewer. (This obviously means that we'll re-render thumbnails instead of using the rendered pages. However, this situation ought to be rare enough for this to not really be a problem.)
Without these changes, clicking on the "Open With Different Viewer"-button on the Firefox fallback bar won't actually do anything and the following is printed in the web-console:
```
Uncaught TypeError: (destructured parameter) is undefined
download resource://pdf.js/web/viewer.js:956
response resource://pdf.js/web/viewer.js:1054
listener resource://pdf.js/web/viewer.js:11891
viewer.js:956:1
```
Furthermore, this patch also fixes `PDFViewerApplication.fallback` to pass in an explicit `sourceEventType` when triggering downloading. While this, on its own, would obviously have been sufficient to fix the bug described above, it seems wrong to outright break backwards compatibility of any older `PDFViewerApplication.download` calls.
Good form type detection is important to get reliable telemetry and to
only show the fallback bar if a form cannot be filled out by the user.
PDF.js only supports AcroForm data, so XFA data is explicitly unsupported
(tracked in issue #2373). However, the previous form type detection
couldn't separate AcroForm and XFA well enough, causing form type
telemetry to be incorrect sometimes and the fallback bar to be shown for
forms that could in fact be filled out by the user.
The solution in this commit is found by studying the specification and
the form documents that are available to us. In a nutshell the rules are:
- There is XFA data if the `XFA` entry is a non-empty array or stream.
- There is AcroForm data if the `Fields` entry is a non-empty array and
it doesn't consist of only document signatures.
The document signatures part was not handled in the old code, causing a
document with only XFA data to also be marked as having AcroForm data.
Moreover, the old code didn't check all the data types.
Now that AcroForm and XFA can be distinguished, the viewer is configured
to only show the fallback bar for documents that only have XFA data. If
a document also has AcroForm data, the viewer can use that to render the
form. We have not found documents where the XFA data was necessary in
that case.
Finally, we include unit tests to ensure that all cases are covered and
move the form type detection out of the `parse` function so that it's
only executed if the document information is actually requested
(potentially making initial parsing a tiny bit faster).
This solution is obviously *not* perfect, since printing being cancelled will thus remove the warning as well. However, a similar problem already exists for saving, since the user may cancel that one as well.
All-in-all, since way cannot really detect with absolute certainty that either saving or printing actually finished, this seems good enough for now.
