Add support for multiple images

This patch adds support for running tests on multiple images. Instead of
parsing just 1 image, it attempts to always parse multiple images from
config files and/or CLI.

To run dox on multiple images from the CLI, you'll have to:

    $ dox -i infra/trusty,infra/f20

The tox.ini `docker:images` option is now a comma-separated list of
images, whereas the dox.yml one is an array of images.

Change-Id: I124c299b208be5c31c63187af754705c48de5693

dox.yml

@@ -1,4 +1,5 @@
-image: infra/trusty
+images:
+    - infra/trusty
 add:
   - requirements.txt
   - test-requirements.txt

dox/cmd.py

@@ -14,6 +14,7 @@
 # limitations under the License.
 
 import argparse
+import functools
 import logging
 
 import dox.commands
@@ -46,8 +47,8 @@ def parse_args():
     parser.add_argument(dest='extra_args', nargs='*',
                         help='args to append to command, or command to run'
                              ' if -c is given')
-    parser.add_argument('-i', '--image', dest='image',
+    parser.add_argument('-i', '--images', dest='images',
-                        help='Base image to use')
+                        help='Base images to use')
     parser.add_argument('-c', '--command', dest='command', default=False,
                         action='store_true',
                         help='Treat arguments as the entire command to run')
@@ -77,9 +78,10 @@ def main():
 def run_dox(args):
 
     # Get Image
-    image = args.image
+    if args.images is None:
-    if args.image is None:
+        images = dox.images.get_images()
-        image = dox.images.get_image()
+    else:
+        images = args.images.split(',')
 
     # Get Command
     if args.command:
@@ -89,7 +91,9 @@ def run_dox(args):
 
     # Run
     try:
-        return dox.runner.Runner(args).run(image, command)
+        run = functools.partial(dox.runner.Runner(args).run,
+                                command=command)
+        map(run, images)
     except Exception:
         logger.error(
             "Operation failed, aborting dox.", exc_info=args.debug)

dox/config/dox_yaml.py

@@ -43,8 +43,8 @@ class DoxYaml(object):
     def exists(self):
         return os.path.exists('dox.yml')
 
-    def get_image(self, image):
+    def get_images(self):
-        return self._open_dox_yaml().get('image', image)
+        return self._open_dox_yaml().get('images', [])
 
     def get_commands(self, extra_args):
         return " ".join([self._open_dox_yaml().get('commands')] + extra_args)

dox/config/tox_ini.py

@@ -43,11 +43,10 @@ class ToxIni(object):
     def exists(self):
         return os.path.exists('tox.ini')
 
-    def get_image(self, image):
+    def get_images(self):
         ini = self._open_tox_ini()
-        if ini.has_option('docker', 'image'):
+        if ini.has_option('docker', 'images'):
-            image = ini.get('docker', 'image')
+            return ini.get('docker', 'images', '').split(',')
-        return image
 
     def get_commands(self, extra_args):
         ini = self._open_tox_ini()

dox/images.py

@@ -14,7 +14,7 @@
 # limitations under the License.
 
 __all__ = [
-    'get_image',
+    'get_images',
 ]
 
 import dox.config.dockerfile
@@ -22,21 +22,24 @@ import dox.config.dox_yaml
 import dox.config.tox_ini
 
 
-def get_image():
+def get_images():
     '''Examine the local environment and figure out where we should run.'''
 
     dockerfile = dox.config.dockerfile.get_dockerfile()
     dox_yaml = dox.config.dox_yaml.get_dox_yaml()
     tox_ini = dox.config.tox_ini.get_tox_ini()
 
-    # Set default image value
     if dockerfile.exists():
-        image = None
+        default_images = []
     else:
-        image = 'ubuntu'
+        # NOTE(flaper87): We should probably raise
+        # `RuntimeError` if no image was specified
+        default_images = ['ubuntu']
 
+    images = []
     if dox_yaml.exists():
-        image = dox_yaml.get_image(image)
+        images = dox_yaml.get_images()
     elif tox_ini.exists():
-        image = tox_ini.get_image(image)
+        images = tox_ini.get_images()
-    return image
+
+    return images or default_images

dox/tests/test_images.py

@@ -29,12 +29,12 @@ from dox.tests import base
 
 
 def get_fake_image(value):
-    if value:
+    if value is not None:
-        def fake_value(self, image):
+        def fake_value(self):
             return value
     else:
-        def fake_value(self, image):
+        def fake_value(self):
-            return image
+            return ['ubuntu']
     return fake_value
 
 
@@ -43,37 +43,38 @@ class TestImages(base.TestCase):
     scenarios = [
         ('have_dockerfile', dict(
             dockerfile=True, tox_ini=False, dox_yaml=False,
-            tox_value=None, dox_value=None, image=None)),
+            tox_value=[], dox_value=[], images=[])),
         ('no_dockerfile', dict(
             dockerfile=False, tox_ini=False, dox_yaml=False,
-            tox_value=None, dox_value=None, image='ubuntu')),
+            tox_value=[], dox_value=[], images=['ubuntu'])),
         ('tox_no_docker', dict(
             dockerfile=False, tox_ini=True, dox_yaml=False,
-            tox_value=None, dox_value=None, image='ubuntu')),
+            tox_value=[], dox_value=[], images=['ubuntu'])),
         ('tox_docker', dict(
             dockerfile=False, tox_ini=True, dox_yaml=False,
-            tox_value='tox_docker', dox_value=None, image='tox_docker')),
+            tox_value=['tox_docker'], dox_value=[], images=['tox_docker'])),
         ('dox_image', dict(
             dockerfile=False, tox_ini=False, dox_yaml=True,
-            tox_value=None, dox_value=None, image='ubuntu')),
+            tox_value=[], dox_value=[], images=['ubuntu'])),
         ('dox_no_image', dict(
             dockerfile=False, tox_ini=False, dox_yaml=True,
-            tox_value=None, dox_value='dox_value', image='dox_value')),
+            tox_value=[], dox_value=['dox_value'], images=['dox_value'])),
         ('both_dox_wins', dict(
             dockerfile=False, tox_ini=True, dox_yaml=True,
-            tox_value='tox_wins', dox_value='dox_wins', image='dox_wins')),
+            tox_value=['tox_wins'], dox_value=['dox_wins'],
+            images=['dox_wins'])),
         ('both_no_dox', dict(
             dockerfile=False, tox_ini=True, dox_yaml=True,
-            tox_value='tox_wins', dox_value=None, image='ubuntu')),
+            tox_value=['tox_wins'], dox_value=[], images=['ubuntu'])),
         ('both_dockerfile_passthru', dict(
             dockerfile=True, tox_ini=True, dox_yaml=True,
-            tox_value=None, dox_value=None, image=None)),
+            tox_value=[], dox_value=[], images=[])),
         ('all_dockerfile_dox_override', dict(
             dockerfile=True, tox_ini=True, dox_yaml=True,
-            tox_value=None, dox_value='dox_wins', image='dox_wins')),
+            tox_value=[], dox_value=['dox_wins'], images=['dox_wins'])),
         ('all_dockerfile_tox_loses', dict(
             dockerfile=True, tox_ini=True, dox_yaml=True,
-            tox_value='tox_wins', dox_value=None, image=None)),
+            tox_value=['tox_wins'], dox_value=[], images=[])),
     ]
 
     def setUp(self):
@@ -88,15 +89,15 @@ class TestImages(base.TestCase):
             'dox.config.tox_ini.ToxIni.exists',
             base.bool_to_fake(self.tox_ini)))
         self.useFixture(fixtures.MonkeyPatch(
-            'dox.config.dox_yaml.DoxYaml.get_image',
+            'dox.config.dox_yaml.DoxYaml.get_images',
             get_fake_image(self.dox_value)))
         self.useFixture(fixtures.MonkeyPatch(
-            'dox.config.tox_ini.ToxIni.get_image',
+            'dox.config.tox_ini.ToxIni.get_images',
             get_fake_image(self.tox_value)))
 
     def test_images(self):
-        image = images.get_image()
+        image = images.get_images()
-        self.assertEqual(image, self.image)
+        self.assertEqual(image, self.images)
 
 
 def load_tests(loader, in_tests, pattern):

tox.ini

@@ -30,4 +30,4 @@ builtins = _
 exclude=.venv,.git,.tox,dist,doc,*lib/python*,*egg,build
 
 [docker]
-image = infra/trusty
+images = infra/trusty