Allow overriding user on the command line

fig/cli/main.py

@@ -276,6 +276,7 @@ def run(self, project, options):
                                   new container name.
             --entrypoint CMD      Override the entrypoint of the image.
             -e KEY=VAL            Set an environment variable (can be used multiple times)
+            -u --user USER        Run as specified user.
             --no-deps             Don't start linked services.
             --rm                  Remove container after run. Ignored in detached mode.
             -T                    Disable pseudo-tty allocation. By default `fig run`
@@ -320,6 +321,10 @@ def run(self, project, options):
 
         if options['--entrypoint']:
             container_options['entrypoint'] = options.get('--entrypoint')
+
+        if options['--user']:
+            container_options['user'] = options.get('--user')
+
         container = service.create_container(
             one_off=True,
             insecure_registry=insecure_registry,

tests/fixtures/user-figfile/fig.yml

@@ -0,0 +1,3 @@
+service:
+  image: busybox:latest
+  command: id

tests/integration/cli_test.py

@@ -1,13 +1,15 @@
 from __future__ import absolute_import
 import sys
 
+from docker.errors import APIError
 from six import StringIO
 from mock import patch
 
 from .testcases import DockerClientTestCase
 from fig.cli.main import TopLevelCommand
 
 
+
 class CLITestCase(DockerClientTestCase):
     def setUp(self):
         super(CLITestCase, self).setUp()
@@ -217,6 +219,21 @@ def test_run_service_with_entrypoint_overridden(self, _):
             u'/bin/echo helloworld'
         )
 
+    @patch('dockerpty.start')
+    def test_run_service_with_user_overridden(self, _):
+        name = 'service'
+        self.command.base_dir = 'tests/fixtures/user-figfile'
+        # NOTE(chmou): available in default busybox and has a shell
+        user = 'sshd'
+        args = ['run', '--user', user, name]
+
+        self.command.dispatch(args, None)
+
+        service = self.project.get_service(name)
+        container = service.containers(stopped=True, one_off=True)[0]
+        container.inspect()
+        self.assertEqual(user, container.dictionary['Config']['User'])
+
     @patch('dockerpty.start')
     def test_run_service_with_environement_overridden(self, _):
         name = 'service'