Fix passing volumes to run with no host path

Technically we shouldn't be passing them as binds, but the daemon
doesn't seem to mind.

Fixes #1380
Signed-off-by: Ben Firshman <ben@firshman.co.uk>

docker/models/containers.py

@@ -885,5 +885,15 @@ def _create_container_args(kwargs):
                                   for p in sorted(port_bindings.keys())]
     binds = create_kwargs['host_config'].get('Binds')
     if binds:
-        create_kwargs['volumes'] = [v.split(':')[1] for v in binds]
+        create_kwargs['volumes'] = [_host_volume_from_bind(v) for v in binds]
     return create_kwargs
+
+
+def _host_volume_from_bind(bind):
+    bits = bind.split(':')
+    if len(bits) == 1:
+        return bits[0]
+    elif len(bits) == 2 and bits[1] in ('ro', 'rw'):
+        return bits[0]
+    else:
+        return bits[1]

tests/unit/models_containers_test.py

@@ -101,6 +101,8 @@ class ContainerCollectionTest(unittest.TestCase):
                 '/home/user1/:/mnt/vol2',
                 '/var/www:/mnt/vol1:ro',
                 'volumename:/mnt/vol3',
+                '/volumewithnohostpath',
+                '/anothervolumewithnohostpath:ro',
             ],
             volumes_from=['container'],
             working_dir='/code'
@@ -118,6 +120,8 @@ class ContainerCollectionTest(unittest.TestCase):
                     '/home/user1/:/mnt/vol2',
                     '/var/www:/mnt/vol1:ro',
                     'volumename:/mnt/vol3',
+                    '/volumewithnohostpath',
+                    '/anothervolumewithnohostpath:ro'
                 ],
                 'BlkioDeviceReadBps': [{'Path': 'foo', 'Rate': 3}],
                 'BlkioDeviceReadIOps': [{'Path': 'foo', 'Rate': 3}],
@@ -183,7 +187,13 @@ class ContainerCollectionTest(unittest.TestCase):
             tty=True,
             user='bob',
             volume_driver='some_driver',
-            volumes=['/mnt/vol2', '/mnt/vol1', '/mnt/vol3'],
+            volumes=[
+                '/mnt/vol2',
+                '/mnt/vol1',
+                '/mnt/vol3',
+                '/volumewithnohostpath',
+                '/anothervolumewithnohostpath'
+            ],
             working_dir='/code'
         )