Auth Strategies (#1257)

* auth strategies

* default to no auth

* rename base auth strategy

* rename base strategy cont.

* refactor auth strategy methods and LocalAuth

* activate old session options even if is falsy value

* move restartOnAuthFail to LegacyAuthStrategy option

* add link to guide item

* update example/shell

* types

src/authStrategies/BaseAuthStrategy.js

@@ -0,0 +1,24 @@
+'use strict';
+
+/**
+ * Base class which all authentication strategies extend
+ */
+class BaseAuthStrategy {
+    constructor() {}
+    setup(client) {
+        this.client = client;
+    }
+    async beforeBrowserInitialized() {}
+    async afterBrowserInitialized() {}
+    async onAuthenticationNeeded() {
+        return {
+            failed: false,
+            restart: false,
+            failureEventPayload: undefined
+        };
+    }
+    async getAuthEventPayload() {}
+    async logout() {}
+}
+
+module.exports = BaseAuthStrategy;

src/authStrategies/LegacySessionAuth.js

@@ -0,0 +1,72 @@
+'use strict';
+
+const BaseAuthStrategy = require('./BaseAuthStrategy');
+
+/**
+ * Legacy session auth strategy
+ * Not compatible with multi-device accounts.
+ * @param {object} options - options
+ * @param {string} options.restartOnAuthFail - Restart client with a new session (i.e. use null 'session' var) if authentication fails
+ * @param {object} options.session - Whatsapp session to restore. If not set, will start a new session
+ * @param {string} options.session.WABrowserId
+ * @param {string} options.session.WASecretBundle
+ * @param {string} options.session.WAToken1
+ * @param {string} options.session.WAToken2
+ */
+class LegacySessionAuth extends BaseAuthStrategy {
+    constructor({ session, restartOnAuthFail }) {
+        super();
+        this.session = session;
+        this.restartOnAuthFail = restartOnAuthFail;
+    }
+
+    async afterBrowserInitialized() {
+        if(this.session) {
+            await this.client.pupPage.evaluateOnNewDocument(session => {
+                if (document.referrer === 'https://whatsapp.com/') {
+                    localStorage.clear();
+                    localStorage.setItem('WABrowserId', session.WABrowserId);
+                    localStorage.setItem('WASecretBundle', session.WASecretBundle);
+                    localStorage.setItem('WAToken1', session.WAToken1);
+                    localStorage.setItem('WAToken2', session.WAToken2);
+                }
+  
+                localStorage.setItem('remember-me', 'true');
+            }, this.session);
+        }
+    }
+
+    async onAuthenticationNeeded() {
+        if(this.session) {
+            this.session = null;
+            return {
+                failed: true,
+                restart: this.restartOnAuthFail,
+                failureEventPayload: 'Unable to log in. Are the session details valid?'
+            };
+        }
+
+        return { failed: false };
+    }
+
+    async getAuthEventPayload() {
+        const isMD = await this.client.pupPage.evaluate(() => {
+            return window.Store.Features.features.MD_BACKEND;
+        });
+
+        if(isMD) throw new Error('Authenticating via JSON session is not supported for MultiDevice-enabled WhatsApp accounts.');
+
+        const localStorage = JSON.parse(await this.client.pupPage.evaluate(() => {
+            return JSON.stringify(window.localStorage);
+        }));
+
+        return {
+            WABrowserId: localStorage.WABrowserId,
+            WASecretBundle: localStorage.WASecretBundle,
+            WAToken1: localStorage.WAToken1,
+            WAToken2: localStorage.WAToken2
+        };
+    }
+}
+
+module.exports = LegacySessionAuth;

src/authStrategies/LocalAuth.js

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+'use strict';
+
+const path = require('path');
+const fs = require('fs');
+const BaseAuthStrategy = require('./BaseAuthStrategy');
+
+/**
+ * Local directory-based authentication
+ * @param {object} options - options
+ * @param {string} options.clientId - Client id to distinguish instances if you are using multiple, otherwise keep null if you are using only one instance
+ * @param {string} options.dataPath - Change the default path for saving session files, default is: "./.wwebjs_auth/" 
+*/
+class LocalAuth extends BaseAuthStrategy {
+    constructor({ clientId, dataPath }={}) {
+        super();
+
+        const idRegex = /^[-_\w]+$/i;
+        if(clientId && !idRegex.test(clientId)) {
+            throw new Error('Invalid clientId. Only alphanumeric characters, underscores and hyphens are allowed.');
+        }
+
+        this.dataPath = path.resolve(dataPath || './.wwebjs_auth/');
+        this.clientId = clientId;
+    }
+
+    async beforeBrowserInitialized() {
+        const puppeteerOpts = this.client.options.puppeteer;
+
+        if(puppeteerOpts.userDataDir) {
+            throw new Error('LocalAuth is not compatible with a user-supplied userDataDir.');
+        }
+
+        const sessionDirName = this.clientId ? `session-${this.clientId}` : 'session';
+        const dirPath = path.join(this.dataPath, sessionDirName);
+
+        fs.mkdirSync(dirPath, { recursive: true });
+        
+        this.client.options.puppeteer = {
+            ...puppeteerOpts,
+            userDataDir: dirPath
+        };
+
+        this.userDataDir = dirPath;
+    }
+
+    async logout() {
+        if (this.userDataDir) {
+            return (fs.rmSync ? fs.rmSync : fs.rmdirSync).call(this.userDataDir, { recursive: true });
+        }
+    }
+
+}
+
+module.exports = LocalAuth;

src/authStrategies/NoAuth.js

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+'use strict';
+
+const BaseAuthStrategy = require('./BaseAuthStrategy');
+
+/**
+ * No session restoring functionality
+ * Will need to authenticate via QR code every time
+*/
+class NoAuth extends BaseAuthStrategy { }
+
+
+module.exports = NoAuth;