diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 14:29:10 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 14:29:10 +0000 |
commit | 2aa4a82499d4becd2284cdb482213d541b8804dd (patch) | |
tree | b80bf8bf13c3766139fbacc530efd0dd9d54394c /devtools/shared/webconsole/throttle.js | |
parent | Initial commit. (diff) | |
download | firefox-2aa4a82499d4becd2284cdb482213d541b8804dd.tar.xz firefox-2aa4a82499d4becd2284cdb482213d541b8804dd.zip |
Adding upstream version 86.0.1.upstream/86.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'devtools/shared/webconsole/throttle.js')
-rw-r--r-- | devtools/shared/webconsole/throttle.js | 469 |
1 files changed, 469 insertions, 0 deletions
diff --git a/devtools/shared/webconsole/throttle.js b/devtools/shared/webconsole/throttle.js new file mode 100644 index 0000000000..2f40605ee8 --- /dev/null +++ b/devtools/shared/webconsole/throttle.js @@ -0,0 +1,469 @@ +/* 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, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +"use strict"; + +const { CC, Ci, Cc } = require("chrome"); + +const ArrayBufferInputStream = CC( + "@mozilla.org/io/arraybuffer-input-stream;1", + "nsIArrayBufferInputStream" +); +const BinaryInputStream = CC( + "@mozilla.org/binaryinputstream;1", + "nsIBinaryInputStream", + "setInputStream" +); + +loader.lazyServiceGetter( + this, + "gActivityDistributor", + "@mozilla.org/network/http-activity-distributor;1", + "nsIHttpActivityDistributor" +); + +const ChromeUtils = require("ChromeUtils"); +const { setTimeout } = require("resource://gre/modules/Timer.jsm"); + +/** + * Construct a new nsIStreamListener that buffers data and provides a + * method to notify another listener when data is available. This is + * used to throttle network data on a per-channel basis. + * + * After construction, @see setOriginalListener must be called on the + * new object. + * + * @param {NetworkThrottleQueue} queue the NetworkThrottleQueue to + * which status changes should be reported + */ +function NetworkThrottleListener(queue) { + this.queue = queue; + this.pendingData = []; + this.pendingException = null; + this.offset = 0; + this.responseStarted = false; + this.activities = {}; +} + +NetworkThrottleListener.prototype = { + QueryInterface: ChromeUtils.generateQI([ + "nsIStreamListener", + "nsIInterfaceRequestor", + ]), + + /** + * Set the original listener for this object. The original listener + * will receive requests from this object when the queue allows data + * through. + * + * @param {nsIStreamListener} originalListener the original listener + * for the channel, to which all requests will be sent + */ + setOriginalListener: function(originalListener) { + this.originalListener = originalListener; + }, + + /** + * @see nsIStreamListener.onStartRequest. + */ + onStartRequest: function(request) { + this.originalListener.onStartRequest(request); + this.queue.start(this); + }, + + /** + * @see nsIStreamListener.onStopRequest. + */ + onStopRequest: function(request, statusCode) { + this.pendingData.push({ request, statusCode }); + this.queue.dataAvailable(this); + }, + + /** + * @see nsIStreamListener.onDataAvailable. + */ + onDataAvailable: function(request, inputStream, offset, count) { + if (this.pendingException) { + throw this.pendingException; + } + + const bin = new BinaryInputStream(inputStream); + const bytes = new ArrayBuffer(count); + bin.readArrayBuffer(count, bytes); + + const stream = new ArrayBufferInputStream(); + stream.setData(bytes, 0, count); + + this.pendingData.push({ request, stream, count }); + this.queue.dataAvailable(this); + }, + + /** + * Allow some buffered data from this object to be forwarded to this + * object's originalListener. + * + * @param {Number} bytesPermitted The maximum number of bytes + * permitted to be sent. + * @return {Object} an object of the form {length, done}, where + * |length| is the number of bytes actually forwarded, and + * |done| is a boolean indicating whether this particular + * request has been completed. (A NetworkThrottleListener + * may be queued multiple times, so this does not mean that + * all available data has been sent.) + */ + sendSomeData: function(bytesPermitted) { + if (this.pendingData.length === 0) { + // Shouldn't happen. + return { length: 0, done: true }; + } + + const { request, stream, count, statusCode } = this.pendingData[0]; + + if (statusCode !== undefined) { + this.pendingData.shift(); + this.originalListener.onStopRequest(request, statusCode); + return { length: 0, done: true }; + } + + if (bytesPermitted > count) { + bytesPermitted = count; + } + + try { + this.originalListener.onDataAvailable( + request, + stream, + this.offset, + bytesPermitted + ); + } catch (e) { + this.pendingException = e; + } + + let done = false; + if (bytesPermitted === count) { + this.pendingData.shift(); + done = true; + } else { + this.pendingData[0].count -= bytesPermitted; + } + + this.offset += bytesPermitted; + // Maybe our state has changed enough to emit an event. + this.maybeEmitEvents(); + + return { length: bytesPermitted, done }; + }, + + /** + * Return the number of pending data requests available for this + * listener. + */ + pendingCount: function() { + return this.pendingData.length; + }, + + /** + * This is called when an http activity event is delivered. This + * object delays the event until the appropriate moment. + */ + addActivityCallback: function( + callback, + httpActivity, + channel, + activityType, + activitySubtype, + timestamp, + extraSizeData, + extraStringData + ) { + const datum = { + callback, + httpActivity, + channel, + activityType, + activitySubtype, + extraSizeData, + extraStringData, + }; + this.activities[activitySubtype] = datum; + + if ( + activitySubtype === + gActivityDistributor.ACTIVITY_SUBTYPE_RESPONSE_COMPLETE + ) { + this.totalSize = extraSizeData; + } + + this.maybeEmitEvents(); + }, + + /** + * This is called for a download throttler when the latency timeout + * has ended. + */ + responseStart: function() { + this.responseStarted = true; + this.maybeEmitEvents(); + }, + + /** + * Check our internal state and emit any http activity events as + * needed. Note that we wait until both our internal state has + * changed and we've received the real http activity event from + * platform. This approach ensures we can both pass on the correct + * data from the original event, and update the reported time to be + * consistent with the delay we're introducing. + */ + maybeEmitEvents: function() { + if (this.responseStarted) { + this.maybeEmit(gActivityDistributor.ACTIVITY_SUBTYPE_RESPONSE_START); + this.maybeEmit(gActivityDistributor.ACTIVITY_SUBTYPE_RESPONSE_HEADER); + } + + if (this.totalSize !== undefined && this.offset >= this.totalSize) { + this.maybeEmit(gActivityDistributor.ACTIVITY_SUBTYPE_RESPONSE_COMPLETE); + this.maybeEmit(gActivityDistributor.ACTIVITY_SUBTYPE_TRANSACTION_CLOSE); + } + }, + + /** + * Emit an event for |code|, if the appropriate entry in + * |activities| is defined. + */ + maybeEmit: function(code) { + if (this.activities[code] !== undefined) { + const { + callback, + httpActivity, + channel, + activityType, + activitySubtype, + extraSizeData, + extraStringData, + } = this.activities[code]; + const now = Date.now() * 1000; + callback( + httpActivity, + channel, + activityType, + activitySubtype, + now, + extraSizeData, + extraStringData + ); + this.activities[code] = undefined; + } + }, +}; + +/** + * Construct a new queue that can be used to throttle the network for + * a group of related network requests. + * + * meanBPS {Number} Mean bytes per second. + * maxBPS {Number} Maximum bytes per second. + * latencyMean {Number} Mean latency in milliseconds. + * latencyMax {Number} Maximum latency in milliseconds. + */ +function NetworkThrottleQueue(meanBPS, maxBPS, latencyMean, latencyMax) { + this.meanBPS = meanBPS; + this.maxBPS = maxBPS; + this.latencyMean = latencyMean; + this.latencyMax = latencyMax; + + this.pendingRequests = new Set(); + this.downloadQueue = []; + this.previousReads = []; + + this.pumping = false; +} + +NetworkThrottleQueue.prototype = { + /** + * A helper function that, given a mean and a maximum, returns a + * random integer between (mean - (max - mean)) and max. + */ + random: function(mean, max) { + return mean - (max - mean) + Math.floor(2 * (max - mean) * Math.random()); + }, + + /** + * A helper function that lets the indicating listener start sending + * data. This is called after the initial round trip time for the + * listener has elapsed. + */ + allowDataFrom: function(throttleListener) { + throttleListener.responseStart(); + this.pendingRequests.delete(throttleListener); + const count = throttleListener.pendingCount(); + for (let i = 0; i < count; ++i) { + this.downloadQueue.push(throttleListener); + } + this.pump(); + }, + + /** + * Notice a new listener object. This is called by the + * NetworkThrottleListener when the request has started. Initially + * a new listener object is put into a "pending" state, until the + * round-trip time has elapsed. This is used to simulate latency. + * + * @param {NetworkThrottleListener} throttleListener the new listener + */ + start: function(throttleListener) { + this.pendingRequests.add(throttleListener); + const delay = this.random(this.latencyMean, this.latencyMax); + if (delay > 0) { + setTimeout(() => this.allowDataFrom(throttleListener), delay); + } else { + this.allowDataFrom(throttleListener); + } + }, + + /** + * Note that new data is available for a given listener. Each time + * data is available, the listener will be re-queued. + * + * @param {NetworkThrottleListener} throttleListener the listener + * which has data available. + */ + dataAvailable: function(throttleListener) { + if (!this.pendingRequests.has(throttleListener)) { + this.downloadQueue.push(throttleListener); + this.pump(); + } + }, + + /** + * An internal function that permits individual listeners to send + * data. + */ + pump: function() { + // A redirect will cause two NetworkThrottleListeners to be on a + // listener chain. In this case, we might recursively call into + // this method. Avoid infinite recursion here. + if (this.pumping) { + return; + } + this.pumping = true; + + const now = Date.now(); + const oneSecondAgo = now - 1000; + + while ( + this.previousReads.length && + this.previousReads[0].when < oneSecondAgo + ) { + this.previousReads.shift(); + } + + const totalBytes = this.previousReads.reduce((sum, elt) => { + return sum + elt.numBytes; + }, 0); + + let thisSliceBytes = this.random(this.meanBPS, this.maxBPS); + if (totalBytes < thisSliceBytes) { + thisSliceBytes -= totalBytes; + let readThisTime = 0; + while (thisSliceBytes > 0 && this.downloadQueue.length) { + const { length, done } = this.downloadQueue[0].sendSomeData( + thisSliceBytes + ); + thisSliceBytes -= length; + readThisTime += length; + if (done) { + this.downloadQueue.shift(); + } + } + this.previousReads.push({ when: now, numBytes: readThisTime }); + } + + // If there is more data to download, then schedule ourselves for + // one second after the oldest previous read. + if (this.downloadQueue.length) { + const when = this.previousReads[0].when + 1000; + setTimeout(this.pump.bind(this), when - now); + } + + this.pumping = false; + }, +}; + +/** + * Construct a new object that can be used to throttle the network for + * a group of related network requests. + * + * @param {Object} An object with the following attributes: + * latencyMean {Number} Mean latency in milliseconds. + * latencyMax {Number} Maximum latency in milliseconds. + * downloadBPSMean {Number} Mean bytes per second for downloads. + * downloadBPSMax {Number} Maximum bytes per second for downloads. + * uploadBPSMean {Number} Mean bytes per second for uploads. + * uploadBPSMax {Number} Maximum bytes per second for uploads. + * + * Download throttling will not be done if downloadBPSMean and + * downloadBPSMax are <= 0. Upload throttling will not be done if + * uploadBPSMean and uploadBPSMax are <= 0. + */ +function NetworkThrottleManager({ + latencyMean, + latencyMax, + downloadBPSMean, + downloadBPSMax, + uploadBPSMean, + uploadBPSMax, +}) { + if (downloadBPSMax <= 0 && downloadBPSMean <= 0) { + this.downloadQueue = null; + } else { + this.downloadQueue = new NetworkThrottleQueue( + downloadBPSMean, + downloadBPSMax, + latencyMean, + latencyMax + ); + } + if (uploadBPSMax <= 0 && uploadBPSMean <= 0) { + this.uploadQueue = null; + } else { + this.uploadQueue = Cc[ + "@mozilla.org/network/throttlequeue;1" + ].createInstance(Ci.nsIInputChannelThrottleQueue); + this.uploadQueue.init(uploadBPSMean, uploadBPSMax); + } +} +exports.NetworkThrottleManager = NetworkThrottleManager; + +NetworkThrottleManager.prototype = { + /** + * Create a new NetworkThrottleListener for a given channel and + * install it using |setNewListener|. + * + * @param {nsITraceableChannel} channel the channel to manage + * @return {NetworkThrottleListener} the new listener, or null if + * download throttling is not being done. + */ + manage: function(channel) { + if (this.downloadQueue) { + const listener = new NetworkThrottleListener(this.downloadQueue); + const originalListener = channel.setNewListener(listener); + listener.setOriginalListener(originalListener); + return listener; + } + return null; + }, + + /** + * Throttle uploads taking place on the given channel. + * + * @param {nsITraceableChannel} channel the channel to manage + */ + manageUpload: function(channel) { + if (this.uploadQueue) { + channel = channel.QueryInterface(Ci.nsIThrottledInputChannel); + channel.throttleQueue = this.uploadQueue; + } + }, +}; |