Find an existing Safari WebDriver process or launch a new one

The old code only ever launched a new WebDriver process. The new code
has been refactored to launch a new instance of the web driver if an
existing process cannot be used.

It's also using `async`/`await` and `const` so it will require a fairly
new version of Node now.

index.js

@@ -3,22 +3,14 @@ var http = require('http');
 var url = require('url');
 
 /**
- * The `safaridriver` does not always start accepting incoming connections immediately. As a result we have to "ping"
- * the driver to figure out when it is safe to start sending commands. This method pings the server, in a callback loop,
- * to determine when the server starts accepting incoming connections.
+ * Use `async`/`await` to provide a `sleep` capability.
  *
- * @param {*} options The options to send to `http.get`.
- * @param {number} limit The maximum number of attempts to make before quitting.
- * @param {Function} done The callback performed when the Safari WebDriver is accepting connections.
+ * @see https://stackoverflow.com/a/39914235/247730
+ * @param {number} ms The time, in milliseconds, to block the event queue.
+ * @returns {Promise} A promise to be resolved when the timeout finishes.
  */
-function ping(options, limit, done) {
- var attempts = 0;
- function error(e) {
- if (attempts <= limit) {
- http.get(options, done).on('error', error);
- }
- }
- http.get(options, done).on('error', error);
+function sleep(ms) {
+ return new Promise(resolve => setTimeout(resolve, ms));
 }
 
 var SafariBrowser = function(baseBrowserDecorator, args, logger) {
@@ -35,24 +27,73 @@ var SafariBrowser = function(baseBrowserDecorator, args, logger) {
  this.name = 'Safari via WebDriver at ' + webDriver;
  var log = logger.create(this.name);
 
+ this.driver = wd.promiseChainRemote(config);
+
+ this.driver.on('status', (info) => {
+ log.debug(info);
+ });
+
+ this.driver.on('command', (eventType, command, response) => {
+ log.debug(`${eventType} ${command} ${response || ''}`);
+ });
+
+ this.driver.on('http', (meth, path, data) => {
+ log.debug(`${meth} ${path} ${data || ''}`);
+ });
+
  this._getOptions = function() {
  return [
  "-p", config.port.toString()
  ];
  }
 
+ /**
+ * This launcher works by checking to see if there is a `/usr/bin/safaridriver` instance running.
+ * It is determined to be running if the web driver API can be reached on the configured host and port.
+ * If it is then it it launches the Karma test runner in a new session. If it is not, it then attempts
+ * to start its own new instance of `/usr/bin/safaridriver` and then connect the Karma test runner in
+ * a new session.
+ *
+ * @param {string} url The URL that the Karma server is listening on.
+ */
  this._start = function(url) {
  var self = this;
 
- log.debug(url);
- // self._execCommand(self._getCommand(), self._getOptions(url));
- ping(config, 100, function() {
- self.driver = wd.remote(config, 'promiseChain');
- self.browser = self.driver.init({});
+ var attempts = 0;
+ // TODO: It would be nice if this was configurable
+ const MAX_ATTEMPTS = 3;
+ async function attachKarma(error) {
+ attempts += 1;
+ if (error && attempts === 1) {
+ log.debug(`attachKarma ${attempts} of ${MAX_ATTEMPTS}`);
+ log.debug(`${self._getCommand()} is not running.`);
+ log.debug(`Attempting to start ${self._getCommand()} ${self._getOptions(url).join(' ')}`);
+ self._execCommand(self._getCommand(), self._getOptions(url));
+ self.browser = self.driver.init({}, attachKarma);
+ } else if (error && attempts <= MAX_ATTEMPTS) {
+ log.debug(`attachKarma ${attempts} of ${MAX_ATTEMPTS}`);
+ // TODO: It would be nice if this was configurable
+ const sleepDuration = 4000;
+ log.debug(`Going to give the driver time to start-up. Sleeping for ${sleepDuration}ms.`);
+ await sleep(sleepDuration);
+ self.browser = self.driver.init({}, attachKarma);
+ } else if (error) {
+ log.error('Could not connect to Safari.');
+ } else {
+ log.debug('Connected to Safari WebDriver');
+ log.debug(`Connecting to ${url}`);
+ self.browser.get(url).done();
+ }
+ }
 
- self.browser.get(url).done();
- });
+ self.browser = self.driver.init({}, attachKarma);
  };
+
+ this.on('kill', (done) => {
+ if (this.browser) {
+ this.browser.quit(() => done());
+ }
+ });
 };
 
 SafariBrowser.prototype = {