[bidi][js] Add high-level logging API

javascript/node/selenium-webdriver/bidi/logInspector.js

@@ -66,11 +66,17 @@ class LogInspector {
   }
 
   removeCallback(id) {
+    let hasId = false
     for (const [, callbacks] of this.listener) {
       if (callbacks.has(id)) {
         callbacks.delete(id)
+        hasId = true
       }
     }
+
+    if (!hasId) {
+      throw Error(`Callback with id ${id} not found`)
+    }
   }
 
   invokeCallbacks(eventType, data) {

javascript/node/selenium-webdriver/lib/script.js

@@ -0,0 +1,63 @@
+// Licensed to the Software Freedom Conservancy (SFC) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The SFC licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+const logInspector = require('../bidi/logInspector')
+
+class Script {
+  #driver
+  #logInspector
+
+  constructor(driver) {
+    this.#driver = driver
+  }
+
+  // This should be done in the constructor.
+  // But since it needs to call async methods we cannot do that in the constructor.
+  // We can have a separate async method that initialises the Script instance.
+  // However, that pattern does not allow chaining the methods as we would like the user to use it.
+  // Since it involves awaiting to get the instance and then another await to call the method.
+  // Using this allows the user to do this "await driver.script().addJavaScriptErrorHandler(callback)"
+  async #init() {
+    if (this.#logInspector !== undefined) {
+      return
+    }
+    this.#logInspector = await logInspector(this.#driver)
+  }
+
+  async addJavaScriptErrorHandler(callback) {
+    await this.#init()
+    return await this.#logInspector.onJavascriptException(callback)
+  }
+
+  async removeJavaScriptErrorHandler(id) {
+    await this.#init()
+    await this.#logInspector.removeCallback(id)
+  }
+
+  async addConsoleMessageHandler(callback) {
+    await this.#init()
+    return this.#logInspector.onConsoleEntry(callback)
+  }
+
+  async removeConsoleMessageHandler(id) {
+    await this.#init()
+
+    await this.#logInspector.removeCallback(id)
+  }
+}
+
+module.exports = Script

javascript/node/selenium-webdriver/lib/webdriver.js

@@ -43,6 +43,7 @@ const { isObject } = require('./util')
 const BIDI = require('../bidi')
 const { PinnedScript } = require('./pinnedScript')
 const JSZip = require('jszip')
+const Script = require('./script')
 
 // Capability names that are defined in the W3C spec.
 const W3C_CAPABILITY_NAMES = new Set([
@@ -654,6 +655,7 @@ function filterNonW3CCaps(capabilities) {
  * @implements {IWebDriver}
  */
 class WebDriver {
+  #script = undefined
   /**
    * @param {!(./session.Session|IThenable<!./session.Session>)} session Either
    *     a known session or a promise that will be resolved to a session.
@@ -1104,6 +1106,16 @@ class WebDriver {
     return new TargetLocator(this)
   }
 
+  script() {
+    // The Script calls the LogInspector which maintains state of the callbacks.
+    // Returning a new instance of the same driver will not work while removing callbacks.
+    if (this.#script === undefined) {
+      this.#script = new Script(this)
+    }
+
+    return this.#script
+  }
+
   validatePrintPageParams(keys, object) {
     let page = {}
     let margin = {}

javascript/node/selenium-webdriver/test/lib/webdriver_script_test.js

@@ -0,0 +1,91 @@
+// Licensed to the Software Freedom Conservancy (SFC) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The SFC licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+'use strict'
+
+const assert = require('node:assert')
+const { Browser } = require('../../')
+const { Pages, suite } = require('../../lib/test')
+const { until } = require('../../index')
+
+suite(
+  function (env) {
+    let driver
+
+    beforeEach(async function () {
+      driver = await env.builder().build()
+    })
+
+    afterEach(async function () {
+      await driver.quit()
+    })
+
+    function delay(ms) {
+      return new Promise((resolve) => setTimeout(resolve, ms))
+    }
+
+    describe('script()', function () {
+      it('can listen to console log', async function () {
+        let log = null
+        const handler = await driver.script().addConsoleMessageHandler((logEntry) => {
+          log = logEntry
+        })
+
+        await driver.get(Pages.logEntryAdded)
+        await driver.findElement({ id: 'consoleLog' }).click()
+
+        await delay(3000)
+
+        assert.equal(log.text, 'Hello, world!')
+        assert.equal(log.realm, null)
+        assert.equal(log.type, 'console')
+        assert.equal(log.level, 'info')
+        assert.equal(log.method, 'log')
+        assert.equal(log.args.length, 1)
+        await driver.script().removeConsoleMessageHandler(handler)
+      })
+
+      it('can listen to javascript error', async function () {
+        let log = null
+        const handler = await driver.script().addJavaScriptErrorHandler((logEntry) => {
+          log = logEntry
+        })
+
+        await driver.get(Pages.logEntryAdded)
+        await driver.findElement({ id: 'jsException' }).click()
+
+        await delay(3000)
+
+        assert.equal(log.text, 'Error: Not working')
+        assert.equal(log.type, 'javascript')
+        assert.equal(log.level, 'error')
+
+        await driver.script().removeJavaScriptErrorHandler(handler)
+      })
+
+      it('throws an error while removing a handler that does not exist', async function () {
+        try {
+          await driver.script().removeJavaScriptErrorHandler(10)
+          assert.fail('Expected error not thrown. Non-existent handler cannot be removed')
+        } catch (e) {
+          assert.strictEqual(e.message, 'Callback with id 10 not found')
+        }
+      })
+    })
+  },
+  { browsers: [Browser.FIREFOX, Browser.CHROME, Browser.EDGE] },
+)