Feature/execute script asyncronously (#141)

* execute script asyncronously in order to effectively use promises
* added travis configuration
* added chromedriver to path on travis
* changed chromedriver to point to executable
* downloading chromedriver on travis
* changed chromedriver version to env var

Author: neverstew

.travis.yml

@@ -18,8 +18,12 @@ jobs:
       node_js: stable
       addons:
         firefox: latest-nightly
-      env: TOXENV=py36 MOZ_HEADLESS=1 GECKODRIVER=0.22.0
+        chrome: stable
+      env: TOXENV=py36 MOZ_HEADLESS=1 GECKODRIVER=0.22.0 CHROMEDRIVER=2.40
       before_install:
+        - wget -O /tmp/chromedriver.zip http://chromedriver.storage.googleapis.com/$CHROMEDRIVER/chromedriver_linux64.zip
+        - mkdir $HOME/chromedriver && unzip /tmp/chromedriver.zip -d $HOME/chromedriver
+        - export PATH=$HOME/chromedriver:$PATH
         - wget -O /tmp/geckodriver.tar.gz https://github.com/mozilla/geckodriver/releases/download/v$GECKODRIVER/geckodriver-v$GECKODRIVER-linux64.tar.gz
         - mkdir $HOME/geckodriver && tar xvf /tmp/geckodriver.tar.gz -C $HOME/geckodriver
         - export PATH=$HOME/geckodriver:$PATH
@@ -36,8 +40,12 @@ jobs:
       node_js: stable
       addons:
         firefox: latest-nightly
-      env: TOXENV=py27 MOZ_HEADLESS=1 GECKODRIVER=0.22.0
+        chrome: stable
+      env: TOXENV=py27 MOZ_HEADLESS=1 GECKODRIVER=0.22.0 CHROMEDRIVER=2.40
       before_install:
+        - wget -O /tmp/chromedriver.zip http://chromedriver.storage.googleapis.com/$CHROMEDRIVER/chromedriver_linux64.zip
+        - mkdir $HOME/chromedriver && unzip /tmp/chromedriver.zip -d $HOME/chromedriver
+        - export PATH=$HOME/chromedriver:$PATH
         - wget -O /tmp/geckodriver.tar.gz https://github.com/mozilla/geckodriver/releases/download/v$GECKODRIVER/geckodriver-v$GECKODRIVER-linux64.tar.gz
         - mkdir $HOME/geckodriver && tar xvf /tmp/geckodriver.tar.gz -C $HOME/geckodriver
         - export PATH=$HOME/geckodriver:$PATH

README.rst

@@ -73,7 +73,11 @@ Contributing
 ------------
 
 Fork the repository and submit PRs with bug fixes and enhancements;
-contributions are very welcome. You can run the tests using
+contributions are very welcome.
+
+Node dependencies must be installed by running `npm install` inside the axe-selenium-python directory.
+
+You can run the tests using
 `tox <https://tox.readthedocs.io/en/latest/>`_:
 
 .. code-block:: bash

axe_selenium_python/axe.py

@@ -33,7 +33,8 @@ def execute(self, context=None, options=None):
         :param context: which page part(s) to analyze and/or what to exclude.
         :param options: dictionary of aXe options.
         """
-        template = "return axe.run(%s).then(function(result){return result;});"
+        template = "var callback = arguments[arguments.length - 1];" \
+                   "axe.run(%s).then(results => callback(results))"
         args = ""
 
         # If context parameter is passed, add to args
@@ -47,7 +48,7 @@ def execute(self, context=None, options=None):
             args += "%s" % options
 
         command = template % args
-        response = self.selenium.execute_script(command)
+        response = self.selenium.execute_async_script(command)
         return response
 
     def report(self, violations):

axe_selenium_python/tests/test_axe.py

@@ -2,7 +2,7 @@
 # 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/.
 
-from os import path
+from os import path, getenv
 
 import pytest
 from selenium import webdriver
@@ -13,21 +13,49 @@
 
 
 @pytest.fixture
-def driver():
+def firefox_driver():
     driver = webdriver.Firefox()
     yield driver
     driver.close()
 
 
+@pytest.fixture
+def chrome_driver():
+    opts = webdriver.ChromeOptions()
+    opts.headless = True
+    opts.add_argument('--no-sandbox')
+    driver_path = getenv('CHROMEDRIVER_PATH')
+    driver = webdriver.Chrome(options=opts, executable_path=driver_path) \
+        if driver_path else webdriver.Chrome(options=opts)
+    yield driver
+    driver.close()
+
+
 @pytest.mark.nondestructive
-def test_run_axe_sample_page(driver):
+def test_run_axe_sample_page_firefox(firefox_driver):
     """Run axe against sample page and verify JSON output is as expected."""
-    driver.get("file://" + _DEFAULT_TEST_FILE)
-    axe = Axe(driver)
-    axe.inject()
-    data = axe.execute()
+    data = _perform_axe_run(firefox_driver)
+
+    assert len(data["inapplicable"]) == 50
+    assert len(data["incomplete"]) == 0
+    assert len(data["passes"]) == 7
+    assert len(data["violations"]) == 8
+
+
+@pytest.mark.nondestructive
+def test_run_axe_sample_page_chrome(chrome_driver):
+    """Run axe against sample page and verify JSON output is as expected."""
+    data = _perform_axe_run(chrome_driver)
 
     assert len(data["inapplicable"]) == 50
     assert len(data["incomplete"]) == 0
     assert len(data["passes"]) == 7
     assert len(data["violations"]) == 8
+
+
+def _perform_axe_run(driver):
+    driver.get("file://" + _DEFAULT_TEST_FILE)
+    axe = Axe(driver)
+    axe.inject()
+    data = axe.execute()
+    return data