Auto merge of #6133 - jgraham:servodriver, r=Ms2ger

This runs tests using the WebDriver protocol without restarting
the browser each time, and is currently enabled with
--product servodriver on the command line

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tests/wpt/config.ini

@@ -1,5 +1,6 @@
 [products]
 servo =
+servodriver =
 
 [web-platform-tests]
 remote_url = https://github.com/w3c/web-platform-tests.git

tests/wpt/config_css.ini

@@ -1,5 +1,6 @@
 [products]
 servo =
+servodriver =
 
 [web-platform-tests]
 name = CSS tests

tests/wpt/harness/wptrunner/browsers/__init__.py

@@ -29,4 +29,5 @@ module global scope.
 product_list = ["b2g",
                 "chrome",
                 "firefox",
-                "servo"]
+                "servo",
+                "servodriver"]

tests/wpt/harness/wptrunner/browsers/firefox.py

@@ -4,6 +4,7 @@
 
 import os
 import subprocess
+import sys
 
 import mozinfo
 from mozprocess import ProcessHandler
@@ -70,7 +71,6 @@ class FirefoxBrowser(Browser):
         self.binary = binary
         self.prefs_root = prefs_root
         self.marionette_port = None
-        self.used_ports.add(self.marionette_port)
         self.runner = None
         self.debug_info = debug_info
         self.profile = None
@@ -81,6 +81,7 @@ class FirefoxBrowser(Browser):
 
     def start(self):
         self.marionette_port = get_free_port(2828, exclude=self.used_ports)
+        self.used_ports.add(self.marionette_port)
 
         env = os.environ.copy()
         env["MOZ_DISABLE_NONLOCAL_CONNECTIONS"] = "1"
@@ -191,7 +192,8 @@ class FirefoxBrowser(Browser):
 
 
         env[env_var] = (os.path.pathsep.join([certutil_dir, env[env_var]])
-                        if env_var in env else certutil_dir)
+                        if env_var in env else certutil_dir).encode(
+                                sys.getfilesystemencoding() or 'utf-8', 'replace')
 
         def certutil(*args):
             cmd = [self.certutil_binary] + list(args)

tests/wpt/harness/wptrunner/browsers/servodriver.py

@@ -0,0 +1,141 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import os
+import subprocess
+import tempfile
+
+from mozprocess import ProcessHandler
+
+from .base import Browser, require_arg, get_free_port, browser_command, ExecutorBrowser
+from ..executors import executor_kwargs as base_executor_kwargs
+from ..executors.executorservodriver import (ServoWebDriverTestharnessExecutor,
+                                             ServoWebDriverRefTestExecutor)
+
+here = os.path.join(os.path.split(__file__)[0])
+
+__wptrunner__ = {"product": "servodriver",
+                 "check_args": "check_args",
+                 "browser": "ServoWebDriverBrowser",
+                 "executor": {"testharness": "ServoWebDriverTestharnessExecutor",
+                              "reftest": "ServoWebDriverRefTestExecutor"},
+                 "browser_kwargs": "browser_kwargs",
+                 "executor_kwargs": "executor_kwargs",
+                 "env_options": "env_options"}
+
+hosts_text = """127.0.0.1 web-platform.test
+127.0.0.1 www.web-platform.test
+127.0.0.1 www1.web-platform.test
+127.0.0.1 www2.web-platform.test
+127.0.0.1 xn--n8j6ds53lwwkrqhv28a.web-platform.test
+127.0.0.1 xn--lve-6lad.web-platform.test
+"""
+
+
+def check_args(**kwargs):
+    require_arg(kwargs, "binary")
+
+
+def browser_kwargs(**kwargs):
+    return {"binary": kwargs["binary"],
+            "debug_info": kwargs["debug_info"]}
+
+
+def executor_kwargs(test_type, server_config, cache_manager, **kwargs):
+    rv = base_executor_kwargs(test_type, server_config,
+                              cache_manager, **kwargs)
+    return rv
+
+
+def env_options():
+    return {"host": "web-platform.test",
+            "bind_hostname": "true",
+            "testharnessreport": "testharnessreport-servodriver.js",
+            "supports_debugger": True}
+
+
+def make_hosts_file():
+    hosts_fd, hosts_path = tempfile.mkstemp()
+    with os.fdopen(hosts_fd, "w") as f:
+        f.write(hosts_text)
+    return hosts_path
+
+
+class ServoWebDriverBrowser(Browser):
+    used_ports = set()
+
+    def __init__(self, logger, binary, debug_info=None, webdriver_host="127.0.0.1"):
+        Browser.__init__(self, logger)
+        self.binary = binary
+        self.webdriver_host = webdriver_host
+        self.webdriver_port = None
+        self.proc = None
+        self.debug_info = debug_info
+        self.hosts_path = make_hosts_file()
+        self.command = None
+
+    def start(self):
+        self.webdriver_port = get_free_port(4444, exclude=self.used_ports)
+        self.used_ports.add(self.webdriver_port)
+
+        env = os.environ.copy()
+        env["HOST_FILE"] = self.hosts_path
+
+        debug_args, command = browser_command(self.binary,
+                                              ["--cpu", "--hard-fail",
+                                               "--webdriver", str(self.webdriver_port),
+                                               "about:blank"],
+                                              self.debug_info)
+
+        self.command = command
+
+        self.command = debug_args + self.command
+
+        if not self.debug_info or not self.debug_info.interactive:
+            self.proc = ProcessHandler(self.command,
+                                       processOutputLine=[self.on_output],
+                                       env=env,
+                                       storeOutput=False)
+            self.proc.run()
+        else:
+            self.proc = subprocess.Popen(self.command, env=env)
+
+        self.logger.debug("Servo Started")
+
+    def stop(self):
+        self.logger.debug("Stopping browser")
+        if self.proc is not None:
+            try:
+                self.proc.kill()
+            except OSError:
+                # This can happen on Windows if the process is already dead
+                pass
+
+    def pid(self):
+        if self.proc is None:
+            return None
+
+        try:
+            return self.proc.pid
+        except AttributeError:
+            return None
+
+    def on_output(self, line):
+        """Write a line of output from the process to the log"""
+        self.logger.process_output(self.pid(),
+                                   line.decode("utf8", "replace"),
+                                   command=" ".join(self.command))
+
+    def is_alive(self):
+        if self.runner:
+            return self.runner.is_running()
+        return False
+
+    def cleanup(self):
+        self.stop()
+
+    def executor_browser(self):
+        assert self.webdriver_port is not None
+        return ExecutorBrowser, {"webdriver_host": self.webdriver_host,
+                                 "webdriver_port": self.webdriver_port}

tests/wpt/harness/wptrunner/executors/executormarionette.py

@@ -157,20 +157,19 @@ class MarionetteProtocol(Protocol):
             let prefInterface = Components.classes["@mozilla.org/preferences-service;1"]
                                           .getService(Components.interfaces.nsIPrefBranch);
             let pref = '%s';
-            let value = '%s';
             let type = prefInterface.getPrefType(pref);
             switch(type) {
                 case prefInterface.PREF_STRING:
-                    prefInterface.setCharPref(pref, value);
+                    prefInterface.setCharPref(pref, '%s');
                     break;
                 case prefInterface.PREF_BOOL:
-                    prefInterface.setBoolPref(pref, value);
+                    prefInterface.setBoolPref(pref, %s);
                     break;
                 case prefInterface.PREF_INT:
-                    prefInterface.setIntPref(pref, value);
+                    prefInterface.setIntPref(pref, %s);
                     break;
             }
-            """ % (name, value)
+            """ % (name, value, value, value)
         self.marionette.execute_script(script)
         self.marionette.set_context(self.marionette.CONTEXT_CONTENT)
 

tests/wpt/harness/wptrunner/executors/executorservodriver.py

@@ -0,0 +1,229 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import json
+import os
+import socket
+import threading
+import time
+import traceback
+
+from .base import (Protocol,
+                   RefTestExecutor,
+                   RefTestImplementation,
+                   TestharnessExecutor,
+                   strip_server)
+import webdriver
+from ..testrunner import Stop
+
+here = os.path.join(os.path.split(__file__)[0])
+
+extra_timeout = 5
+
+
+class ServoWebDriverProtocol(Protocol):
+    def __init__(self, executor, browser, capabilities, **kwargs):
+        Protocol.__init__(self, executor, browser)
+        self.capabilities = capabilities
+        self.host = browser.webdriver_host
+        self.port = browser.webdriver_port
+        self.session = None
+
+    def setup(self, runner):
+        """Connect to browser via WebDriver."""
+        self.runner = runner
+
+        session_started = False
+        try:
+            self.session = webdriver.Session(self.host, self.port)
+            self.session.start()
+        except:
+            self.logger.warning(
+                "Connecting with WebDriver failed:\n%s" % traceback.format_exc())
+        else:
+            self.logger.debug("session started")
+            session_started = True
+
+        if not session_started:
+            self.logger.warning("Failed to connect via WebDriver")
+            self.executor.runner.send_message("init_failed")
+        else:
+            self.executor.runner.send_message("init_succeeded")
+
+    def teardown(self):
+        self.logger.debug("Hanging up on WebDriver session")
+        try:
+            self.session.end()
+        except:
+            pass
+
+    def is_alive(self):
+        try:
+            # Get a simple property over the connection
+            self.session.handle
+        # TODO what exception?
+        except Exception:
+            return False
+        return True
+
+    def after_connect(self):
+        pass
+
+    def wait(self):
+        while True:
+            try:
+                self.session.execute_async_script("")
+            except webdriver.TimeoutException:
+                pass
+            except (socket.timeout, IOError):
+                break
+            except Exception as e:
+                self.logger.error(traceback.format_exc(e))
+                break
+
+
+class ServoWebDriverRun(object):
+    def __init__(self, func, session, url, timeout):
+        self.func = func
+        self.result = None
+        self.session = session
+        self.url = url
+        self.timeout = timeout
+        self.result_flag = threading.Event()
+
+    def run(self):
+        timeout = self.timeout
+
+        try:
+            self.session.timeouts.script = timeout + extra_timeout
+        except IOError:
+            self.logger.error("Lost webdriver connection")
+            return Stop
+
+        executor = threading.Thread(target=self._run)
+        executor.start()
+
+        flag = self.result_flag.wait(timeout + 2 * extra_timeout)
+        if self.result is None:
+            assert not flag
+            self.result = False, ("EXTERNAL-TIMEOUT", None)
+
+        return self.result
+
+    def _run(self):
+        try:
+            self.result = True, self.func(self.session, self.url, self.timeout)
+        except webdriver.TimeoutException:
+            self.result = False, ("EXTERNAL-TIMEOUT", None)
+        except (socket.timeout, IOError):
+            self.result = False, ("CRASH", None)
+        except Exception as e:
+            message = getattr(e, "message", "")
+            if message:
+                message += "\n"
+            message += traceback.format_exc(e)
+            self.result = False, ("ERROR", e)
+        finally:
+            self.result_flag.set()
+
+
+def timeout_func(timeout):
+    if timeout:
+        t0 = time.time()
+        return lambda: time.time() - t0 > timeout + extra_timeout
+    else:
+        return lambda: False
+
+
+class ServoWebDriverTestharnessExecutor(TestharnessExecutor):
+    def __init__(self, browser, server_config, timeout_multiplier=1,
+                 close_after_done=True, capabilities=None, debug_info=None):
+        TestharnessExecutor.__init__(self, browser, server_config, timeout_multiplier=1,
+                                     debug_info=None)
+        self.protocol = ServoWebDriverProtocol(self, browser, capabilities=capabilities)
+        with open(os.path.join(here, "testharness_servodriver.js")) as f:
+            self.script = f.read()
+
+    def on_protocol_change(self, new_protocol):
+        pass
+
+    def is_alive(self):
+        return self.protocol.is_alive()
+
+    def do_test(self, test):
+        url = self.test_url(test)
+
+        success, data = ServoWebDriverRun(self.do_testharness,
+                                          self.protocol.session,
+                                          url,
+                                          test.timeout * self.timeout_multiplier).run()
+
+        if success:
+            return self.convert_result(test, data)
+
+        return (test.result_cls(*data), [])
+
+    def do_testharness(self, session, url, timeout):
+        session.url = url
+        result = json.loads(
+            session.execute_async_script(
+                self.script % {"abs_url": url,
+                               "url": strip_server(url),
+                               "timeout_multiplier": self.timeout_multiplier,
+                               "timeout": timeout * 1000}))
+        if "test" not in result:
+            result["test"] = strip_server(url)
+        return result
+
+
+class TimeoutError(Exception):
+    pass
+
+
+class ServoWebDriverRefTestExecutor(RefTestExecutor):
+    def __init__(self, browser, server_config, timeout_multiplier=1,
+                 screenshot_cache=None, capabilities=None, debug_info=None):
+        """Selenium WebDriver-based executor for reftests"""
+        RefTestExecutor.__init__(self,
+                                 browser,
+                                 server_config,
+                                 screenshot_cache=screenshot_cache,
+                                 timeout_multiplier=timeout_multiplier,
+                                 debug_info=debug_info)
+        self.protocol = ServoWebDriverProtocol(self, browser,
+                                               capabilities=capabilities)
+        self.implementation = RefTestImplementation(self)
+
+        with open(os.path.join(here, "reftest-wait_servodriver.js")) as f:
+            self.wait_script = f.read()
+
+    def is_alive(self):
+        return self.protocol.is_alive()
+
+    def do_test(self, test):
+        try:
+            result = self.implementation.run_test(test)
+            return self.convert_result(test, result)
+        except IOError:
+            return test.result_cls("CRASH", None), []
+        except TimeoutError:
+            return test.result_cls("TIMEOUT", None), []
+        except Exception as e:
+            message = getattr(e, "message", "")
+            if message:
+                message += "\n"
+            message += traceback.format_exc(e)
+            return test.result_cls("ERROR", message), []
+
+    def screenshot(self, test):
+        timeout = test.timeout * self.timeout_multiplier if self.debug_info is None else None
+        return ServoWebDriverRun(self._screenshot,
+                                 self.protocol.session,
+                                 self.test_url(test),
+                                 timeout).run()
+
+    def _screenshot(self, session, url, timeout):
+        session.url = url
+        session.execute_async_script(self.wait_script)
+        return session.screenshot()

tests/wpt/harness/wptrunner/executors/reftest-wait_servodriver.js

@@ -0,0 +1,20 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+callback = arguments[arguments.length - 1];
+
+function check_done() {
+    if (!document.body.classList.contains('reftest-wait')) {
+        callback();
+    } else {
+        setTimeout(check_done, 50);
+    }
+}
+
+if (document.readyState === 'complete') {
+    check_done();
+} else {
+    addEventListener("load", check_done);
+}

tests/wpt/harness/wptrunner/executors/testharness_servodriver.js

@@ -0,0 +1,6 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+window.__wd_results_callback__ = arguments[arguments.length - 1];
+window.__wd_results_timer__ = setTimeout(timeout, %(timeout)s);

tests/wpt/harness/wptrunner/executors/webdriver.py

@@ -0,0 +1,587 @@
+import errno
+import httplib
+import json
+import socket
+import time
+import urlparse
+from collections import defaultdict
+
+element_key = "element-6066-11e4-a52e-4f735466cecf"
+
+
+class WebDriverException(Exception):
+    http_status = None
+    status_code = None
+
+    def __init__(self, message):
+        self.message = message
+
+
+class ElementNotSelectableException(WebDriverException):
+    http_status = 400
+    status_code = "element not selectable"
+
+
+class ElementNotVisibleException(WebDriverException):
+    http_status = 400
+    status_code = "element not visible"
+
+
+class InvalidArgumentException(WebDriverException):
+    http_status = 400
+    status_code = "invalid argument"
+
+
+class InvalidCookieDomainException(WebDriverException):
+    http_status = 400
+    status_code = "invalid cookie domain"
+
+
+class InvalidElementCoordinatesException(WebDriverException):
+    http_status = 400
+    status_code = "invalid element coordinates"
+
+
+class InvalidElementStateException(WebDriverException):
+    http_status = 400
+    status_code = "invalid cookie domain"
+
+
+class InvalidSelectorException(WebDriverException):
+    http_status = 400
+    status_code = "invalid selector"
+
+
+class InvalidSessionIdException(WebDriverException):
+    http_status = 404
+    status_code = "invalid session id"
+
+
+class JavascriptErrorException(WebDriverException):
+    http_status = 500
+    status_code = "javascript error"
+
+
+class MoveTargetOutOfBoundsException(WebDriverException):
+    http_status = 500
+    status_code = "move target out of bounds"
+
+
+class NoSuchAlertException(WebDriverException):
+    http_status = 400
+    status_code = "no such alert"
+
+
+class NoSuchElementException(WebDriverException):
+    http_status = 404
+    status_code = "no such element"
+
+
+class NoSuchFrameException(WebDriverException):
+    http_status = 400
+    status_code = "no such frame"
+
+
+class NoSuchWindowException(WebDriverException):
+    http_status = 400
+    status_code = "no such window"
+
+
+class ScriptTimeoutException(WebDriverException):
+    http_status = 408
+    status_code = "script timeout"
+
+
+class SessionNotCreatedException(WebDriverException):
+    http_status = 500
+    status_code = "session not created"
+
+
+class StaleElementReferenceException(WebDriverException):
+    http_status = 400
+    status_code = "stale element reference"
+
+
+class TimeoutException(WebDriverException):
+    http_status = 408
+    status_code = "timeout"
+
+
+class UnableToSetCookieException(WebDriverException):
+    http_status = 500
+    status_code = "unable to set cookie"
+
+
+class UnexpectedAlertOpenException(WebDriverException):
+    http_status = 500
+    status_code = "unexpected alert open"
+
+
+class UnknownErrorException(WebDriverException):
+    http_status = 500
+    status_code = "unknown error"
+
+
+class UnknownCommandException(WebDriverException):
+    http_status = (404, 405)
+    status_code = "unknown command"
+
+
+class UnsupportedOperationException(WebDriverException):
+    http_status = 500
+    status_code = "unsupported operation"
+
+
+def group_exceptions():
+    exceptions = defaultdict(dict)
+    for item in _objs:
+        if type(item) == type and issubclass(item, WebDriverException):
+            if not isinstance(item.http_status, tuple):
+                statuses = (item.http_status,)
+            else:
+                statuses = item.http_status
+
+            for status in statuses:
+                exceptions[status][item.status_code] = item
+    return exceptions
+
+
+_objs = locals().values()
+_exceptions = group_exceptions()
+del _objs
+del group_exceptions
+
+
+def wait_for_port(host, port, timeout=60):
+    """ Wait for the specified Marionette host/port to be available."""
+    starttime = time.time()
+    poll_interval = 0.1
+    while time.time() - starttime < timeout:
+        sock = None
+        try:
+            sock = socket.socket()
+            sock.connect((host, port))
+            return True
+        except socket.error as e:
+            if e[0] != errno.ECONNREFUSED:
+                raise
+        finally:
+            if sock:
+                sock.close()
+        time.sleep(poll_interval)
+    return False
+
+
+class Transport(object):
+    def __init__(self, host, port, url_prefix="", port_timeout=60):
+        self.host = host
+        self.port = port
+        self.port_timeout = port_timeout
+        if url_prefix == "":
+            self.path_prefix = "/"
+        else:
+            self.path_prefix = "/%s/" % url_prefix.strip("/")
+        self._connection = None
+
+    def connect(self):
+        wait_for_port(self.host, self.port, self.port_timeout)
+        self._connection = httplib.HTTPConnection(self.host, self.port)
+
+    def close_connection(self):
+        if self._connection:
+            self._connection.close()
+        self._connection = None
+
+    def url(self, suffix):
+        return urlparse.urljoin(self.url_prefix, suffix)
+
+    def send(self, method, url, body=None, headers=None, key=None):
+        if not self._connection:
+            self.connect()
+
+        if body is None and method == "POST":
+            body = {}
+
+        if isinstance(body, dict):
+            body = json.dumps(body)
+
+        if isinstance(body, unicode):
+            body = body.encode("utf-8")
+
+        if headers is None:
+            headers = {}
+
+        url = self.path_prefix + url
+
+        self._connection.request(method, url, body, headers)
+
+        try:
+            resp = self._connection.getresponse()
+        except Exception:
+            # This should probably be more specific
+            raise IOError
+        body = resp.read()
+
+        try:
+            data = json.loads(body)
+        except:
+            raise
+            raise WebDriverException("Could not parse response body as JSON: %s" % body)
+
+        if resp.status != 200:
+            cls = _exceptions.get(resp.status, {}).get(data.get("status", None), WebDriverException)
+            raise cls(data.get("message", ""))
+
+        if key is not None:
+            data = data[key]
+
+        if not data:
+            data = None
+
+        return data
+
+
+def command(func):
+    def inner(self, *args, **kwargs):
+        if hasattr(self, "session"):
+            session_id = self.session.session_id
+        else:
+            session_id = self.session_id
+
+        if session_id is None:
+            raise SessionNotCreatedException("Session not created")
+        return func(self, *args, **kwargs)
+
+    inner.__name__ = func.__name__
+    inner.__doc__ = func.__doc__
+
+    return inner
+
+
+class Timeouts(object):
+    def __init__(self, session):
+        self.session = session
+        self._script = 30
+        self._load = 0
+        self._implicit_wait = 0
+
+    def _set_timeouts(self, name, value):
+        body = {"type": name,
+                "ms": value * 1000}
+        return self.session.send_command("POST", "timeouts", body)
+
+    @property
+    def script(self):
+        return self._script
+
+    @script.setter
+    def script(self, value):
+        self._set_timeouts("script", value)
+        self._script = value
+
+    @property
+    def load(self):
+        return self._load
+
+    @load.setter
+    def set_load(self, value):
+        self._set_timeouts("page load", value)
+        self._script = value
+
+    @property
+    def implicit_wait(self):
+        return self._implicit_wait
+
+    @implicit_wait.setter
+    def implicit_wait(self, value):
+        self._set_timeouts("implicit wait", value)
+        self._implicit_wait = value
+
+
+class Window(object):
+    def __init__(self, session):
+        self.session = session
+
+    @property
+    @command
+    def size(self):
+        return self.session.send_command("GET", "window/size")
+
+    @size.setter
+    @command
+    def size(self, (height, width)):
+        body = {"width": width,
+                "height": height}
+
+        return self.session.send_command("POST", "window/size", body)
+
+    @property
+    @command
+    def maximize(self):
+        return self.session.send_command("POST", "window/maximize")
+
+
+class Find(object):
+    def __init__(self, session):
+        self.session = session
+
+    @command
+    def css(self, selector, all=True):
+        return self._find_element("css selector", selector, all)
+
+    def _find_element(self, strategy, selector, all):
+        route = "elements" if all else "element"
+
+        body = {"using": strategy,
+                "value": selector}
+
+        data = self.session.send_command("POST", route, body, key="value")
+
+        if all:
+            rv = [self.session._element(item) for item in data]
+        else:
+            rv = self.session._element(data)
+
+        return rv
+
+
+class Session(object):
+    def __init__(self, host, port, url_prefix="", desired_capabilities=None, port_timeout=60):
+        self.transport = Transport(host, port, url_prefix, port_timeout)
+        self.desired_capabilities = desired_capabilities
+        self.session_id = None
+        self.timeouts = None
+        self.window = None
+        self.find = None
+        self._element_cache = {}
+
+    def start(self):
+        desired_capabilities = self.desired_capabilities if self.desired_capabilities else {}
+        body = {"capabilities": {"desiredCapabilites": desired_capabilities}}
+
+        rv = self.transport.send("POST", "session", body=body)
+        self.session_id = rv["sessionId"]
+
+        self.timeouts = Timeouts(self)
+        self.window = Window(self)
+        self.find = Find(self)
+
+        return rv["value"]
+
+    @command
+    def end(self):
+        url = "session/%s" % self.session_id
+        self.transport.send("DELETE", url)
+        self.session_id = None
+        self.timeouts = None
+        self.window = None
+        self.find = None
+        self.transport.close_connection()
+
+    def __enter__(self):
+        resp = self.start()
+        if resp.error:
+            raise Exception(resp)
+        return self
+
+    def __exit__(self, *args, **kwargs):
+        resp = self.end()
+        if resp.error:
+            raise Exception(resp)
+
+    def send_command(self, method, url, body=None, key=None):
+        url = urlparse.urljoin("session/%s/" % self.session_id, url)
+        return self.transport.send(method, url, body, key=key)
+
+    @property
+    @command
+    def url(self):
+        return self.send_command("GET", "url", key="value")
+
+    @url.setter
+    @command
+    def url(self, url):
+        if urlparse.urlsplit(url).netloc is None:
+            return self.url(url)
+        body = {"url": url}
+        return self.send_command("POST", "url", body)
+
+    @command
+    def back(self):
+        return self.send_command("POST", "back")
+
+    @command
+    def forward(self):
+        return self.send_command("POST", "forward")
+
+    @command
+    def refresh(self):
+        return self.send_command("POST", "refresh")
+
+    @property
+    @command
+    def title(self):
+        return self.send_command("GET", "title", key="value")
+
+    @property
+    @command
+    def handle(self):
+        return self.send_command("GET", "window_handle", key="value")
+
+    @handle.setter
+    @command
+    def handle(self, handle):
+        body = {"handle": handle}
+        return self.send_command("POST", "window", body=body)
+
+    def switch_frame(self, frame):
+        if frame == "parent":
+            url = "frame/parent"
+            body = None
+        else:
+            url = "frame"
+            if isinstance(frame, Element):
+                body = {"id": frame.json()}
+            else:
+                body = {"id": frame}
+        print body
+        return self.send_command("POST", url, body)
+
+    @command
+    def close(self):
+        return self.send_command("DELETE", "window_handle")
+
+    @property
+    @command
+    def handles(self):
+        return self.send_command("GET", "window_handles", key="value")
+
+    @property
+    @command
+    def active_element(self):
+        data = self.send_command("GET", "element/active", key="value")
+        if data is not None:
+            return self._element(data)
+
+    def _element(self, data):
+        elem_id = data[element_key]
+        assert elem_id
+        if elem_id in self._element_cache:
+            return self._element_cache[elem_id]
+        return Element(self, elem_id)
+
+    @command
+    def cookies(self, name=None):
+        if name is None:
+            url = "cookie"
+        else:
+            url = "cookie/%s" % name
+        return self.send_command("GET", url, {}, key="value")
+
+    @command
+    def set_cookie(self, name, value, path=None, domain=None, secure=None, expiry=None):
+        body = {"name": name,
+                "value": value}
+        if path is not None:
+            body["path"] = path
+        if domain is not None:
+            body["domain"] = domain
+        if secure is not None:
+            body["secure"] = secure
+        if expiry is not None:
+            body["expiry"] = expiry
+        self.send_command("POST", "cookie", body)
+
+    def delete_cookie(self, name=None):
+        if name is None:
+            url = "cookie"
+        else:
+            url = "cookie/%s" % name
+        self.send_command("DELETE", url, {}, key="value")
+
+    #[...]
+
+    @command
+    def execute_script(self, script, args=None):
+        if args is None:
+            args = []
+
+        body = {
+            "script": script,
+            "args": args
+        }
+        return self.send_command("POST", "execute", body, key="value")
+
+    @command
+    def execute_async_script(self, script, args=None):
+        if args is None:
+            args = []
+
+        body = {
+            "script": script,
+            "args": args
+        }
+        return self.send_command("POST", "execute_async", body, key="value")
+
+    #[...]
+
+    @command
+    def screenshot(self):
+        return self.send_command("GET", "screenshot", key="value")
+
+
+class Element(object):
+    def __init__(self, session, id):
+        self.session = session
+        self.id = id
+        assert id not in self.session._element_cache
+        self.session._element_cache[self.id] = self
+
+    def json(self):
+        return {element_key: self.id}
+
+    @property
+    def session_id(self):
+        return self.session.session_id
+
+    def url(self, suffix):
+        return "element/%s/%s" % (self.id, suffix)
+
+    @command
+    def find_element(self, strategy, selector):
+        body = {"using": strategy,
+                "value": selector}
+
+        elem = self.session.send_command("POST", self.url("element"), body, key="value")
+        return self.session.element(elem)
+
+    @command
+    def click(self):
+        self.session.send_command("POST", self.url("click"), {})
+
+    @command
+    def tap(self):
+        self.session.send_command("POST", self.url("tap"), {})
+
+    @command
+    def clear(self):
+        self.session.send_command("POST", self.url("clear"), {})
+
+    @command
+    def send_keys(self, keys):
+        if isinstance(keys, (str, unicode)):
+            keys = [char for char in keys]
+
+        body = {"value": keys}
+
+        return self.session.send_command("POST", self.url("value"), body)
+
+    @property
+    @command
+    def text(self):
+        return self.session.send_command("GET", self.url("text"), key="value")
+
+    @property
+    @command
+    def name(self):
+        return self.session.send_command("GET", self.url("name"), key="value")

tests/wpt/harness/wptrunner/testharnessreport-servodriver.js

@@ -0,0 +1,25 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+setup({output:%(output)d});
+
+add_completion_callback(function() {
+    add_completion_callback(function (tests, status) {
+        var test_results = tests.map(function(x) {
+            return {name:x.name, status:x.status, message:x.message, stack:x.stack}
+        });
+        var results = JSON.stringify({tests:test_results,
+                                      status: status.status,
+                                      message: status.message,
+                                      stack: status.stack});
+        (function done() {
+            if (window.__wd_results_callback__) {
+                clearTimeout(__wd_results_timer__);
+                __wd_results_callback__(results)
+            } else {
+                setTimeout(done, 20);
+            }
+        })()
+    })
+});