Creates a ChromeDriver for Selenium that uses authenticated proxy

ChromeDriverProxied.kt

import org.openqa.selenium.WebDriver
import org.openqa.selenium.chrome.ChromeDriver
import org.openqa.selenium.chrome.ChromeOptions
import java.net.URI
import java.nio.file.FileSystems
import java.nio.file.Files

object ChromeDriverProxied {

    operator fun get(
        proxyHost: String, proxyPort: Int,
        proxyUser: String, proxyPass: String
    ): WebDriver {
        val tempDir = Files.createTempDirectory("chrome-driver-proxied")

        val manifestJsonPath = tempDir.resolve("manifest.json")
        Files.writeString(manifestJsonPath, MANIFEST_JSON_TEMPLATE)

        val backgroundJsPath = tempDir.resolve("background.js")
        Files.writeString(backgroundJsPath, BACKGROUND_JS_TEMPLATE.format(proxyHost, proxyPort, proxyUser, proxyPass))

        val zipFile = tempDir.resolve("proxy_auth_plugin.zip")
        val zipFileUri = URI.create("jar:${zipFile.toUri()}")
        val env = mapOf(
            "create" to "true",
            "encoding" to "UTF-8"
        )
        FileSystems.newFileSystem(zipFileUri, env).use { fs ->
            Files.copy(manifestJsonPath, fs.getPath(manifestJsonPath.fileName.toString()))
            Files.copy(backgroundJsPath, fs.getPath(backgroundJsPath.fileName.toString()))
        }

        val options = ChromeOptions().addExtensions(zipFile.toFile())
        return ChromeDriver(options)
    }

    private const val MANIFEST_JSON_TEMPLATE = """{
  "version": "1.0.0",
  "manifest_version": 2,
  "name": "Chrome Proxy",
  "permissions": [
    "proxy",
    "tabs",
    "unlimitedStorage",
    "storage",
    "<all_urls>",
    "webRequest",
    "webRequestBlocking"
  ],
  "background": {
    "scripts": ["background.js"]
  },
  "minimum_chrome_version":"22.0.0"
}"""

    private const val BACKGROUND_JS_TEMPLATE = """var config = {
  mode: "fixed_servers",
  rules: {
    singleProxy: {
      scheme: "http",
      host: "%s",
      port: parseInt(%s)
    },
    bypassList: ["localhost"]
  }
};

chrome.proxy.settings.set({value: config, scope: "regular"}, function() {});

function callbackFn(details) {
return {
authCredentials: {
username: "%s",
password: "%s"
}
};
}

chrome.webRequest.onAuthRequired.addListener(
callbackFn,
{urls: ["<all_urls>"]},
['blocking']
);"""

}