如何通过Gradle运行Protractor测试并内置启动Selenium服务？

Absolutely! You can totally decouple your Gradle setup from local machine dependencies by leveraging npm packages directly within your project and using Gradle's built-in tools to manage the process—no more relying on system-wide command line calls. Here's a step-by-step refactor to make this work:

First, use the com.github.node-gradle.node plugin to handle Node.js installation and npm package management directly in your project. This plugin will auto-download Node.js if it's not present locally, eliminating local setup dependencies. Add this to your build.gradle:

plugins {
    id 'com.github.node-gradle.node' version '7.0.1' // Use the latest stable version
}

node {
    download = true // Auto-download Node.js if missing
    version = '20.10.0' // Specify your required Node.js version
    npmVersion = '10.2.3' // Match with a compatible npm version
}

Create or update a package.json in your project root to define your E2E dependencies:

{
  "devDependencies": {
    "protractor": "~7.0.0",
    "webdriver-manager": "~12.1.9"
  }
}

Then add a Gradle task to install these dependencies locally:

task installProtractor(type: NpmTask) {
    args = ['install']
}

Instead of calling the global webdriver-manager, use the locally installed binary from node_modules. We'll add a task to start the server, wait for it to be ready, and a cleanup task to stop it after tests:

import java.net.HttpURLConnection
import java.net.URL

task startSeleniumServer(type: NpmTask, dependsOn: installProtractor) {
    args = ['run', 'webdriver-manager', 'start']
    ignoreExitValue = true // Let the server run in the background
    doFirst {
        // Ensure webdriver binaries are up-to-date before starting the server
        project.exec {
            commandLine 'npm', 'run', 'webdriver-manager', 'update'
        }
    }
    doLast {
        // Wait for Selenium server to be ready (adjust timeout as needed)
        def seleniumUrl = new URL('http://localhost:4444/wd/hub/status')
        def timeout = 30000 // 30 seconds
        def startTime = System.currentTimeMillis()
        boolean serverReady = false
        
        while (!serverReady && (System.currentTimeMillis() - startTime) < timeout) {
            try {
                HttpURLConnection connection = seleniumUrl.openConnection()
                connection.setRequestMethod('GET')
                serverReady = (connection.responseCode == 200)
                connection.disconnect()
            } catch (Exception e) {
                // Server not ready yet, wait and retry
                Thread.sleep(1000)
            }
        }
        
        if (!serverReady) {
            throw new GradleException("Selenium server failed to start within ${timeout}ms")
        }
    }
}

// Cleanup task to stop Selenium server after tests
task stopSeleniumServer(type: Exec) {
    // Linux/macOS command; replace with `taskkill /F /IM node.exe /FI "WINDOWTITLE eq webdriver-manager start"` for Windows
    commandLine 'pkill', '-f', 'webdriver-manager start'
    ignoreExitValue = true // Ignore error if server isn't running
}

Modify your runProtractor task to use the local Protractor binary, and link it to the server lifecycle tasks:

task runProtractor(type: NpmTask, dependsOn: [installProtractor, startSeleniumServer]) {
    args = ['run', 'protractor', 'src/test/javascript/e2e/conf.js']
    finalizedBy stopSeleniumServer // Ensure server stops even if tests fail
}

• Protractor Config Tweak: In your conf.js, make sure directConnect: false and seleniumAddress: 'http://localhost:4444/wd/hub' are set to use the local server.
• Cross-Platform Compatibility: Adjust the stopSeleniumServer command for Windows (as noted in the code comment) or use a small Node script to kill the server cross-platform.
• Caching: The Node plugin caches the downloaded Node.js version, so subsequent builds will be faster.

内容的提问来源于stack exchange，提问作者Joe