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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
// Refrences to the progress listeners to keep them from being gc'ed
// before they are called.
const progressListeners = new Set();
export class ScreenshotParent extends JSWindowActorParent {
getDimensions(params) {
return this.sendQuery("GetDimensions", params);
}
}
ChromeUtils.registerWindowActor("Screenshot", {
parent: {
},
child: {
},
});
function loadContentWindow(browser, url) {
let uri;
try {
uri = Services.io.newURI(url);
} catch (e) {
let msg = `Invalid URL passed to loadContentWindow(): ${url}`;
console.error(msg);
return Promise.reject(new Error(msg));
}
const principal = Services.scriptSecurityManager.getSystemPrincipal();
return new Promise(resolve => {
let oa = E10SUtils.predictOriginAttributes({
browser,
});
let loadURIOptions = {
triggeringPrincipal: principal,
remoteType: E10SUtils.getRemoteTypeForURI(
url,
true,
false,
E10SUtils.DEFAULT_REMOTE_TYPE,
null,
oa
),
};
browser.loadURI(uri, loadURIOptions);
let { webProgress } = browser;
let progressListener = {
onLocationChange(progress, request, location, flags) {
// Ignore inner-frame events
if (!progress.isTopLevel) {
return;
}
// Ignore events that don't change the document
if (flags & Ci.nsIWebProgressListener.LOCATION_CHANGE_SAME_DOCUMENT) {
return;
}
// Ignore the initial about:blank, unless about:blank is requested
if (location.spec == "about:blank" && uri.spec != "about:blank") {
return;
}
progressListeners.delete(progressListener);
webProgress.removeProgressListener(progressListener);
resolve();
},
QueryInterface: ChromeUtils.generateQI([
"nsIWebProgressListener",
"nsISupportsWeakReference",
]),
};
progressListeners.add(progressListener);
webProgress.addProgressListener(
progressListener,
Ci.nsIWebProgress.NOTIFY_LOCATION
);
});
}
async function takeScreenshot(
fullWidth,
fullHeight,
contentWidth,
contentHeight,
path,
url
) {
let frame;
try {
frame = new HiddenFrame();
let windowlessBrowser = await frame.get();
let doc = windowlessBrowser.document;
let browser = doc.createXULElement("browser");
browser.setAttribute("remote", "true");
browser.setAttribute("type", "content");
browser.setAttribute(
"style",
`width: ${contentWidth}px; min-width: ${contentWidth}px; height: ${contentHeight}px; min-height: ${contentHeight}px;`
);
browser.setAttribute("maychangeremoteness", "true");
doc.documentElement.appendChild(browser);
await loadContentWindow(browser, url);
let actor =
browser.browsingContext.currentWindowGlobal.getActor("Screenshot");
let dimensions = await actor.getDimensions();
let canvas = doc.createElementNS(
"html:canvas"
);
let context = canvas.getContext("2d");
let width = dimensions.innerWidth;
let height = dimensions.innerHeight;
if (fullWidth) {
width += dimensions.scrollMaxX - dimensions.scrollMinX;
}
if (fullHeight) {
height += dimensions.scrollMaxY - dimensions.scrollMinY;
}
canvas.width = width;
canvas.height = height;
let rect = new DOMRect(0, 0, width, height);
let snapshot =
await browser.browsingContext.currentWindowGlobal.drawSnapshot(
rect,
1,
"rgb(255, 255, 255)"
);
context.drawImage(snapshot, 0, 0);
snapshot.close();
let blob = await new Promise(resolve => canvas.toBlob(resolve));
let reader = await new Promise(resolve => {
let fr = new FileReader();
fr.onloadend = () => resolve(fr);
fr.readAsArrayBuffer(blob);
});
await IOUtils.write(path, new Uint8Array(reader.result));
dump("Screenshot saved to: " + path + "\n");
} catch (e) {
dump("Failure taking screenshot: " + e + "\n");
} finally {
if (frame) {
frame.destroy();
}
}
}
export let HeadlessShell = {
async handleCmdLineArgs(cmdLine, URLlist) {
try {
// Don't quit even though we don't create a window
Services.startup.enterLastWindowClosingSurvivalArea();
// Default options
let fullWidth = true;
let fullHeight = true;
// Most common screen resolution of Firefox users
let contentWidth = 1366;
let contentHeight = 768;
// Parse `window-size`
try {
var dimensionsStr = cmdLine.handleFlagWithParam("window-size", true);
} catch (e) {
dump("expected format: --window-size width[,height]\n");
return;
}
if (dimensionsStr) {
let success;
let dimensions = dimensionsStr.split(",", 2);
if (dimensions.length == 1) {
success = dimensions[0] > 0;
if (success) {
fullWidth = false;
fullHeight = true;
contentWidth = dimensions[0];
}
} else {
success = dimensions[0] > 0 && dimensions[1] > 0;
if (success) {
fullWidth = false;
fullHeight = false;
contentWidth = dimensions[0];
contentHeight = dimensions[1];
}
}
if (!success) {
dump("expected format: --window-size width[,height]\n");
return;
}
}
let urlOrFileToSave = null;
try {
urlOrFileToSave = cmdLine.handleFlagWithParam("screenshot", true);
} catch (e) {
// We know that the flag exists so we only get here if there was no parameter.
cmdLine.handleFlag("screenshot", true); // Remove `screenshot`
}
// Assume that the remaining arguments that do not start
// with a hyphen are URLs
for (let i = 0; i < cmdLine.length; ++i) {
const argument = cmdLine.getArgument(i);
if (argument.startsWith("-")) {
dump(`Warning: unrecognized command line flag ${argument}\n`);
// To emulate the pre-nsICommandLine behavior, we ignore
// the argument after an unrecognized flag.
++i;
} else {
URLlist.push(argument);
}
}
let path = null;
if (urlOrFileToSave && !URLlist.length) {
// URL was specified next to "-screenshot"
URLlist.push(urlOrFileToSave);
} else {
path = urlOrFileToSave;
}
if (!path) {
path = PathUtils.join(cmdLine.workingDirectory.path, "screenshot.png");
}
if (URLlist.length == 1) {
await takeScreenshot(
fullWidth,
fullHeight,
contentWidth,
contentHeight,
path,
URLlist[0]
);
} else {
dump("expected exactly one URL when using `screenshot`\n");
}
} finally {
Services.startup.exitLastWindowClosingSurvivalArea();
Services.startup.quit(Ci.nsIAppStartup.eForceQuit);
}
},
};