Add support for docker run --tmpfs flag.

Signed-off-by: Philip Walls <pawalls@rabidgeek.com>

compose/config/config.py

@@ -591,7 +591,7 @@ def process_service(service_config):
     if 'extra_hosts' in service_dict:
         service_dict['extra_hosts'] = parse_extra_hosts(service_dict['extra_hosts'])
 
-    for field in ['dns', 'dns_search']:
+    for field in ['dns', 'dns_search', 'tmpfs']:
         if field in service_dict:
             service_dict[field] = to_list(service_dict[field])
 
@@ -730,7 +730,7 @@ def merge_service_dicts(base, override, version):
     ]:
         md.merge_field(field, operator.add, default=[])
 
-    for field in ['dns', 'dns_search', 'env_file']:
+    for field in ['dns', 'dns_search', 'env_file', 'tmpfs']:
         md.merge_field(field, merge_list_or_string)
 
     for field in set(ALLOWED_KEYS) - set(md):

compose/config/config_schema_v1.json

@@ -104,6 +104,7 @@
         "shm_size": {"type": ["number", "string"]},
         "stdin_open": {"type": "boolean"},
         "stop_signal": {"type": "string"},
+        "tmpfs": {"$ref": "#/definitions/string_or_list"},
         "tty": {"type": "boolean"},
         "ulimits": {
           "type": "object",

compose/config/config_schema_v2.0.json

@@ -184,6 +184,7 @@
         "shm_size": {"type": ["number", "string"]},
         "stdin_open": {"type": "boolean"},
         "stop_signal": {"type": "string"},
+        "tmpfs": {"$ref": "#/definitions/string_or_list"},
         "tty": {"type": "boolean"},
         "ulimits": {
           "type": "object",

compose/service.py

@@ -668,6 +668,7 @@ class Service(object):
             cgroup_parent=options.get('cgroup_parent'),
             cpu_quota=options.get('cpu_quota'),
             shm_size=options.get('shm_size'),
+            tmpfs=options.get('tmpfs'),
         )
 
     def build(self, no_cache=False, pull=False, force_rm=False):

docs/compose-file.md

@@ -226,6 +226,15 @@ Custom DNS search domains. Can be a single value or a list.
       - dc1.example.com
       - dc2.example.com
 
+### tmpfs
+
+Mount a temporary file system inside the container. Can be a single value or a list.
+
+    tmpfs: /run
+    tmpfs:
+      - /run
+      - /tmp
+
 ### entrypoint
 
 Override the default entrypoint.

docs/extends.md

@@ -302,8 +302,8 @@ replaces the old value.
 > This is because `build` and `image` cannot be used together in a version 1
 > file.
 
-For the **multi-value options** `ports`, `expose`, `external_links`, `dns` and
-`dns_search`, Compose concatenates both sets of values:
+For the **multi-value options** `ports`, `expose`, `external_links`, `dns`,
+`dns_search`, and `tmpfs`, Compose concatenates both sets of values:
 
     # original service
     expose:

requirements.txt

@@ -3,7 +3,7 @@ cached-property==1.2.0
 dockerpty==0.4.1
 docopt==0.6.1
 enum34==1.0.4
-git+https://github.com/docker/docker-py.git@d8be3e0fce60fbe25be088b64bccbcee83effdb1#egg=docker-py
+git+https://github.com/docker/docker-py.git@8c4546f8c8f52bb2923834783a17beb5bb89a724#egg=docker-py
 jsonschema==2.5.1
 requests==2.7.0
 six==1.7.3

tests/integration/service_test.py

@@ -875,6 +875,11 @@ class ServiceTest(DockerClientTestCase):
         container = create_and_start_container(service)
         self.assertEqual(container.get('HostConfig.DnsSearch'), ['dc1.example.com', 'dc2.example.com'])
 
+    def test_tmpfs(self):
+        service = self.create_service('web', tmpfs=['/run'])
+        container = create_and_start_container(service)
+        self.assertEqual(container.get('HostConfig.Tmpfs'), {'/run': ''})
+
     def test_working_dir_param(self):
         service = self.create_service('container', working_dir='/working/dir/sample')
         container = service.create_container()

tests/unit/config/config_test.py

@@ -1194,6 +1194,21 @@ class ConfigTest(unittest.TestCase):
             }
         ]
 
+    def test_tmpfs_option(self):
+        actual = config.load(build_config_details({
+            'web': {
+                'image': 'alpine',
+                'tmpfs': '/run',
+            }
+        }))
+        assert actual.services == [
+            {
+                'name': 'web',
+                'image': 'alpine',
+                'tmpfs': ['/run'],
+            }
+        ]
+
     def test_merge_service_dicts_from_files_with_extends_in_base(self):
         base = {
             'volumes': ['.:/app'],