Remove selenium dependency when not using selenium tests

Closes-Bug: 1377372
Change-Id: I6a493989d7280eaa2a1c999a9d1be4365aa77d52
(cherry picked from commit aad4565d9f64a97f10a9528f2c0efc5039343f2c)

1 files changed, 60 insertions, 43 deletions

diff --git a/horizon/test/webdriver.py b/horizon/test/webdriver.py
index 0974e91fe..8750c9dcf 100644
--- a/horizon/test/webdriver.py
+++ b/horizon/test/webdriver.py
@@ -17,62 +17,79 @@
 #   limitations under the License.
 #
 
+import logging
+import os
 import platform
 import shutil
 import subprocess
 
-from selenium.common import exceptions as selenium_exceptions
-from selenium.webdriver import firefox
+LOG = logging.getLogger(__name__)
 
+try:
+    # NOTE: Several distribution can't ship selenium due to its
+    # non-free license. So they have to patch it out of test-requirements.txt
+    # Avoid import failure and force not running selenium tests.
+    # The entire file is encapsulated in the try block because the classes
+    # inherit from the firefox class contained in selenium.webdriver, and
+    # python will throw a NameError if the import is skipped.
+    from selenium.common import exceptions as selenium_exceptions
+    from selenium.webdriver import firefox
 
-class FirefoxBinary(firefox.firefox_binary.FirefoxBinary):
-    """Workarounds selenium firefox issues.
+    class FirefoxBinary(firefox.firefox_binary.FirefoxBinary):
+        """Workarounds selenium firefox issues.
 
-    There is race condition in the way firefox is spawned. The exact cause
-    hasn't been properly diagnosed yet but it's around:
+        There is race condition in the way firefox is spawned. The exact cause
+        hasn't been properly diagnosed yet but it's around:
 
-    - getting a free port from the OS with selenium.webdriver.common.utils
-      free_port(),
+        - getting a free port from the OS with selenium.webdriver.common.utils
+        free_port(),
 
-    - release the port immediately but record it in ff prefs so that ff can
-      listen on that port for the internal http server.
+        - release the port immediately but record it in ff prefs so that ff can
+        listen on that port for the internal http server.
 
-    It has been observed that this leads to hanging processes for 'firefox
-    -silent'.
-    """
+        It has been observed that this leads to hanging processes for 'firefox
+        -silent'.
+        """
 
-    def _start_from_profile_path(self, path):
-        self._firefox_env["XRE_PROFILE_PATH"] = path
+        def _start_from_profile_path(self, path):
+            self._firefox_env["XRE_PROFILE_PATH"] = path
 
-        if platform.system().lower() == 'linux':
-            self._modify_link_library_path()
-        command = [self._start_cmd, "-silent"]
-        if self.command_line is not None:
-            for cli in self.command_line:
-                command.append(cli)
+            if platform.system().lower() == 'linux':
+                self._modify_link_library_path()
+            command = [self._start_cmd, "-silent"]
+            if self.command_line is not None:
+                for cli in self.command_line:
+                    command.append(cli)
 
-# The following exists upstream and is known to create hanging firefoxes,
-# leading to zombies.
-#        subprocess.Popen(command, stdout=self._log_file,
-#              stderr=subprocess.STDOUT,
-#              env=self._firefox_env).communicate()
-        command[1] = '-foreground'
-        self.process = subprocess.Popen(
-            command, stdout=self._log_file, stderr=subprocess.STDOUT,
-            env=self._firefox_env)
+    # The following exists upstream and is known to create hanging firefoxes,
+    # leading to zombies.
+    #        subprocess.Popen(command, stdout=self._log_file,
+    #              stderr=subprocess.STDOUT,
+    #              env=self._firefox_env).communicate()
+            command[1] = '-foreground'
+            self.process = subprocess.Popen(
+                command, stdout=self._log_file, stderr=subprocess.STDOUT,
+                env=self._firefox_env)
 
+    class WebDriver(firefox.webdriver.WebDriver):
+        """Workarounds selenium firefox issues."""
 
-class WebDriver(firefox.webdriver.WebDriver):
-    """Workarounds selenium firefox issues."""
+        def __init__(self, firefox_profile=None, firefox_binary=None,
+                     timeout=30, capabilities=None, proxy=None):
+            try:
+                super(WebDriver, self).__init__(
+                    firefox_profile, FirefoxBinary(), timeout, capabilities,
+                    proxy)
+            except selenium_exceptions.WebDriverException:
+                # If we can't start, cleanup profile
+                shutil.rmtree(self.profile.path)
+                if self.profile.tempfolder is not None:
+                    shutil.rmtree(self.profile.tempfolder)
+                raise
 
-    def __init__(self, firefox_profile=None, firefox_binary=None, timeout=30,
-                 capabilities=None, proxy=None):
-        try:
-            super(WebDriver, self).__init__(
-                firefox_profile, FirefoxBinary(), timeout, capabilities, proxy)
-        except selenium_exceptions.WebDriverException:
-            # If we can't start, cleanup profile
-            shutil.rmtree(self.profile.path)
-            if self.profile.tempfolder is not None:
-                shutil.rmtree(self.profile.tempfolder)
-            raise
+except ImportError as e:
+    # NOTE(saschpe): Several distribution can't ship selenium due to its
+    # non-free license. So they have to patch it out of test-requirements.txt
+    # Avoid import failure and force not running selenium tests.
+    LOG.warning("{0}, force WITH_SELENIUM=False".format(str(e)))
+    os.environ['WITH_SELENIUM'] = ''