DevTools: [Persistence] implement automapping

third_party/WebKit/Source/devtools/front_end/persistence/Automapping.js

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * @constructor
+ * @param {!WebInspector.Workspace} workspace
+ * @param {function(!WebInspector.PersistenceBinding)} onBindingCreated
+ * @param {function(!WebInspector.PersistenceBinding)} onBindingRemoved
+ */
+WebInspector.Automapping = function(workspace, onBindingCreated, onBindingRemoved)
+{
+    this._workspace = workspace;
+
+    this._onBindingCreated = onBindingCreated;
+    this._onBindingRemoved = onBindingRemoved;
+    /** @type {!Set<!WebInspector.PersistenceBinding>} */
+    this._bindings = new Set();
+
+    /** @type {!Map<string, !WebInspector.UISourceCode>} */
+    this._fileSystemUISourceCodes = new Map();
+    this._sweepThrottler = new WebInspector.Throttler(100);
+
+    var pathEncoder = new WebInspector.Automapping.PathEncoder();
+    this._filesIndex = new WebInspector.Automapping.FilePathIndex(pathEncoder);
+    this._projectFoldersIndex = new WebInspector.Automapping.FolderIndex(pathEncoder);
+    this._activeFoldersIndex = new WebInspector.Automapping.FolderIndex(pathEncoder);
+
+    this._eventListeners = [
+        this._workspace.addEventListener(WebInspector.Workspace.Events.UISourceCodeAdded, event => this._onUISourceCodeAdded(/** @type {!WebInspector.UISourceCode} */(event.data))),
+        this._workspace.addEventListener(WebInspector.Workspace.Events.UISourceCodeRemoved, event => this._onUISourceCodeRemoved(/** @type {!WebInspector.UISourceCode} */(event.data))),
+        this._workspace.addEventListener(WebInspector.Workspace.Events.ProjectAdded, event => this._onProjectAdded(/** @type {!WebInspector.Project} */(event.data)), this),
+        this._workspace.addEventListener(WebInspector.Workspace.Events.ProjectRemoved, event => this._onProjectRemoved(/** @type {!WebInspector.Project} */(event.data)), this),
+    ];
+
+    for (var fileSystem of workspace.projects())
+        this._onProjectAdded(fileSystem);
+    for (var uiSourceCode of workspace.uiSourceCodes())
+        this._onUISourceCodeAdded(uiSourceCode);
+}
+
+WebInspector.Automapping._binding = Symbol("Automapping.Binding");
+WebInspector.Automapping._processingPromise = Symbol("Automapping.ProcessingPromise");
+WebInspector.Automapping._metadata = Symbol("Automapping.Metadata");
+
+WebInspector.Automapping.prototype = {
+    _scheduleRemap: function()
+    {
+        for (var binding of this._bindings.valuesArray())
+            this._unbindNetwork(binding.network);
+        this._scheduleSweep();
+    },
+
+    _scheduleSweep: function()
+    {
+        this._sweepThrottler.schedule(sweepUnmapped.bind(this));
+
+        /**
+         * @this {WebInspector.Automapping}
+         * @return {!Promise}
+         */
+        function sweepUnmapped()
+        {
+            var networkProjects = this._workspace.projectsForType(WebInspector.projectTypes.Network);
+            for (var networkProject of networkProjects) {
+                for (var uiSourceCode of networkProject.uiSourceCodes())
+                    this._bindNetwork(uiSourceCode);
+            }
+            this._onSweepHappenedForTest();
+            return Promise.resolve();
+        }
+    },
+
+    _onSweepHappenedForTest: function() { },
+
+    /**
+     * @param {!WebInspector.Project} project
+     */
+    _onProjectRemoved: function(project)
+    {
+        for (var uiSourceCode of project.uiSourceCodes())
+            this._onUISourceCodeRemoved(uiSourceCode);
+        if (project.type() !== WebInspector.projectTypes.FileSystem)
+            return;
+        var fileSystem = /** @type {!WebInspector.FileSystemWorkspaceBinding.FileSystem} */(project);
+        for (var gitFolder of fileSystem.gitFolders())
+            this._projectFoldersIndex.removeFolder(gitFolder);
+        this._projectFoldersIndex.removeFolder(fileSystem.fileSystemPath());
+        this._scheduleRemap();
+    },
+
+    /**
+     * @param {!WebInspector.Project} project
+     */
+    _onProjectAdded: function(project)
+    {
+        if (project.type() !== WebInspector.projectTypes.FileSystem)
+            return;
+        var fileSystem = /** @type {!WebInspector.FileSystemWorkspaceBinding.FileSystem} */(project);
+        for (var gitFolder of fileSystem.gitFolders())
+            this._projectFoldersIndex.addFolder(gitFolder);
+        this._projectFoldersIndex.addFolder(fileSystem.fileSystemPath());
+        this._scheduleRemap();
+    },
+
+    /**
+     * @param {!WebInspector.UISourceCode} uiSourceCode
+     */
+    _onUISourceCodeAdded: function(uiSourceCode)
+    {
+        if (uiSourceCode.project().type() === WebInspector.projectTypes.FileSystem) {
+            this._filesIndex.addPath(uiSourceCode.url());
+            this._fileSystemUISourceCodes.set(uiSourceCode.url(), uiSourceCode);
+            this._scheduleSweep();
+        } else if (uiSourceCode.project().type() === WebInspector.projectTypes.Network) {
+            this._bindNetwork(uiSourceCode);
+        }
+    },
+
+    /**
+     * @param {!WebInspector.UISourceCode} uiSourceCode
+     */
+    _onUISourceCodeRemoved: function(uiSourceCode)
+    {
+        if (uiSourceCode.project().type() === WebInspector.projectTypes.FileSystem) {
+            this._filesIndex.removePath(uiSourceCode.url());
+            this._fileSystemUISourceCodes.delete(uiSourceCode.url());
+            var binding = uiSourceCode[WebInspector.Automapping._binding];
+            if (binding)
+                this._unbindNetwork(binding.network);
+        } else if (uiSourceCode.project().type() === WebInspector.projectTypes.Network) {
+            this._unbindNetwork(uiSourceCode);
+        }
+    },
+
+    /**
+     * @param {!WebInspector.UISourceCode} networkSourceCode
+     */
+    _bindNetwork: function(networkSourceCode)
+    {
+        if (networkSourceCode[WebInspector.Automapping._processingPromise] || networkSourceCode[WebInspector.Automapping._binding])
+            return;
+        var createBindingPromise = this._createBinding(networkSourceCode).then(onBinding.bind(this));
+        networkSourceCode[WebInspector.Automapping._processingPromise] = createBindingPromise;
+
+        /**
+         * @param {?WebInspector.PersistenceBinding} binding
+         * @this {WebInspector.Automapping}
+         */
+        function onBinding(binding)
+        {
+            if (networkSourceCode[WebInspector.Automapping._processingPromise] !== createBindingPromise)
+                return;
+            networkSourceCode[WebInspector.Automapping._processingPromise] = null;
+            if (!binding) {
+                this._onBindingFailedForTest();
+                return;
+            }
+
+            this._bindings.add(binding);
+            binding.network[WebInspector.Automapping._binding] = binding;
+            binding.fileSystem[WebInspector.Automapping._binding] = binding;
+            if (binding.exactMatch) {
+                var projectFolder = this._projectFoldersIndex.closestParentFolder(binding.fileSystem.url());
+                var newFolderAdded = projectFolder ? this._activeFoldersIndex.addFolder(projectFolder) : false;
+                if (newFolderAdded)
+                    this._scheduleSweep();
+            }
+            this._onBindingCreated.call(null, binding);
+        }
+    },
+
+    _onBindingFailedForTest: function() { },
+
+    /**
+     * @param {!WebInspector.UISourceCode} networkSourceCode
+     */
+    _unbindNetwork: function(networkSourceCode)
+    {
+        if (networkSourceCode[WebInspector.Automapping._processingPromise]) {
+            networkSourceCode[WebInspector.Automapping._processingPromise] = null;
+            return;
+        }
+        var binding = networkSourceCode[WebInspector.Automapping._binding];
+        if (!binding)
+            return;
+
+        this._bindings.delete(binding);
+        binding.network[WebInspector.Automapping._binding] = null;
+        binding.fileSystem[WebInspector.Automapping._binding] = null;
+        if (binding.exactMatch) {
+            var projectFolder = this._projectFoldersIndex.closestParentFolder(binding.fileSystem.url());
+            if (projectFolder)
+                this._activeFoldersIndex.removeFolder(projectFolder);
+        }
+        this._onBindingRemoved.call(null, binding);
+    },
+
+    /**
+     * @param {!WebInspector.UISourceCode} networkSourceCode
+     * @return {!Promise<?WebInspector.PersistenceBinding>}
+     */
+    _createBinding: function(networkSourceCode)
+    {
+        var networkPath = WebInspector.ParsedURL.extractPath(networkSourceCode.url());
+        if (networkPath === null)
+            return Promise.resolve(/** @type {?WebInspector.PersistenceBinding} */(null));
+
+        if (networkPath.endsWith("/"))
+            networkPath += "index.html";
+        var similarFiles = this._filesIndex.similarFiles(networkPath).map(path => this._fileSystemUISourceCodes.get(path));
+        if (!similarFiles.length)
+            return Promise.resolve(/** @type {?WebInspector.PersistenceBinding} */(null));
+
+        return this._pullMetadatas(similarFiles.concat(networkSourceCode)).then(onMetadatas.bind(this));
+
+        /**
+         * @this {WebInspector.Automapping}
+         */
+        function onMetadatas()
+        {
+            var activeFiles = similarFiles.filter(file => !!this._activeFoldersIndex.closestParentFolder(file.url()));
+            var networkMetadata = networkSourceCode[WebInspector.Automapping._metadata];
+            if (!networkMetadata || (!networkMetadata.modificationTime && typeof networkMetadata.contentSize !== "number")) {
+                // If networkSourceCode does not have metadata, try to match against active folders.
+                if (activeFiles.length !== 1)
+                    return null;
+                return new WebInspector.PersistenceBinding(networkSourceCode, activeFiles[0], false);
+            }
+
+            // Try to find exact matches, prioritizing active folders.
+            var exactMatches = this._filterWithMetadata(activeFiles, networkMetadata);
+            if (!exactMatches.length)
+                exactMatches = this._filterWithMetadata(similarFiles, networkMetadata);
+            if (exactMatches.length !== 1)
+                return null;
+            return new WebInspector.PersistenceBinding(networkSourceCode, exactMatches[0], true);
+        }
+    },
+
+    /**
+     * @param {!Array<!WebInspector.UISourceCode>} uiSourceCodes
+     * @return {!Promise}
+     */
+    _pullMetadatas: function(uiSourceCodes)
+    {
+        var promises = uiSourceCodes.map(file => fetchMetadata(file));
+        return Promise.all(promises);
+
+        /**
+         * @param {!WebInspector.UISourceCode} file
+         * @return {!Promise}
+         */
+        function fetchMetadata(file)
+        {
+            return file.requestMetadata().then(metadata => file[WebInspector.Automapping._metadata] = metadata);
+        }
+    },
+
+    /**
+     * @param {!Array<!WebInspector.UISourceCode>} files
+     * @param {!WebInspector.UISourceCodeMetadata} networkMetadata
+     * @return {!Array<!WebInspector.UISourceCode>}
+     */
+    _filterWithMetadata: function(files, networkMetadata)
+    {
+        return files.filter(file => {
+            var fileMetadata = file[WebInspector.Automapping._metadata];
+            if (!fileMetadata)
+                return false;
+            // Allow a second of difference due to network timestamps lack of precision.
+            var timeMatches = !networkMetadata.modificationTime || Math.abs(networkMetadata.modificationTime - fileMetadata.modificationTime) < 1000;
+            var contentMatches = !networkMetadata.contentSize || fileMetadata.contentSize === networkMetadata.contentSize;
+            return timeMatches && contentMatches;
+        });
+    }
+}
+
+/**
+ * @constructor
+ */
+WebInspector.Automapping.PathEncoder = function()
+{
+    /** @type {!WebInspector.CharacterIdMap<string>} */
+    this._encoder = new WebInspector.CharacterIdMap();
+}
+
+WebInspector.Automapping.PathEncoder.prototype = {
+    /**
+     * @param {string} path
+     * @return {string}
+     */
+    encode: function(path)
+    {
+        return path.split("/").map(token => this._encoder.toChar(token)).join("");
+    },
+
+    /**
+     * @param {string} path
+     * @return {string}
+     */
+    decode: function(path)
+    {
+        return path.split("").map(token => this._encoder.fromChar(token)).join("/");
+    }
+}
+
+/**
+ * @constructor
+ * @param {!WebInspector.Automapping.PathEncoder} encoder
+ */
+WebInspector.Automapping.FilePathIndex = function(encoder)
+{
+    this._encoder = encoder;
+    this._reversedIndex = new WebInspector.Trie();
+}
+
+WebInspector.Automapping.FilePathIndex.prototype = {
+    /**
+     * @param {string} path
+     */
+    addPath: function(path)
+    {
+        var encodedPath = this._encoder.encode(path);
+        this._reversedIndex.add(encodedPath.reverse());
+    },
+
+    /**
+     * @param {string} path
+     */
+    removePath: function(path)
+    {
+        var encodedPath = this._encoder.encode(path);
+        this._reversedIndex.remove(encodedPath.reverse());
+    },
+
+    /**
+     * @param {string} networkPath
+     * @return {!Array<string>}
+     */
+    similarFiles: function(networkPath)
+    {
+        var encodedPath = this._encoder.encode(networkPath);
+        var longestCommonPrefix = this._reversedIndex.longestPrefix(encodedPath.reverse(), false);
+        if (!longestCommonPrefix)
+            return [];
+        return this._reversedIndex.words(longestCommonPrefix).map(encodedPath => this._encoder.decode(encodedPath.reverse()));
+    },
+}
+
+/**
+ * @constructor
+ * @param {!WebInspector.Automapping.PathEncoder} encoder
+ */
+WebInspector.Automapping.FolderIndex = function(encoder)
+{
+    this._encoder = encoder;
+    this._index = new WebInspector.Trie();
+    /** @type {!Map<string, number>} */
+    this._folderCount = new Map();
+}
+
+WebInspector.Automapping.FolderIndex.prototype = {
+    /**
+     * @param {string} path
+     * @return {boolean}
+     */
+    addFolder: function(path)
+    {
+        if (path.endsWith("/"))
+            path = path.substring(0, path.length - 1);
+        var encodedPath = this._encoder.encode(path);
+        this._index.add(encodedPath);
+        var count = this._folderCount.get(encodedPath) || 0;
+        this._folderCount.set(encodedPath, count + 1);
+        return count === 0;
+    },
+
+    /**
+     * @param {string} path
+     * @return {boolean}
+     */
+    removeFolder: function(path)
+    {
+        if (path.endsWith("/"))
+            path = path.substring(0, path.length - 1);
+        var encodedPath = this._encoder.encode(path);
+        var count = this._folderCount.get(encodedPath) || 0;
+        if (!count)
+            return false;
+        if (count > 1) {
+            this._folderCount.set(encodedPath, count - 1);
+            return false;
+        }
+        this._index.remove(encodedPath);
+        this._folderCount.delete(encodedPath);
+        return true;
+    },
+
+    /**
+     * @param {string} path
+     * @return {string}
+     */
+    closestParentFolder: function(path)
+    {
+        var encodedPath = this._encoder.encode(path);
+        var commonPrefix = this._index.longestPrefix(encodedPath, true);
+        return this._encoder.decode(commonPrefix);
+    }
+}