Add support to kolla_docker for tmpfs mounts

Partial-Bug: #1897276

Change-Id: Ia06da456a7f26f0f2ceebc35eb88c0da0767e1c6

3 files changed, 83 insertions, 1 deletions

diff --git a/ansible/library/kolla_docker.py b/ansible/library/kolla_docker.py
index 224c42458..c76392eda 100644
--- a/ansible/library/kolla_docker.py
+++ b/ansible/library/kolla_docker.py
@@ -176,6 +176,11 @@ options:
       - How many times to attempt a restart if 'on-failure' policy is set
     type: int
     default: 10
+  tmpfs:
+    description:
+      - List of paths to mount as tmpfs.
+    required: False
+    type: list
   volumes:
     description:
       - Set volumes for docker to use
@@ -342,6 +347,7 @@ class DockerWorker(object):
             self.compare_labels(container_info) or
             self.compare_privileged(container_info) or
             self.compare_pid_mode(container_info) or
+            self.compare_tmpfs(container_info) or
             self.compare_volumes(container_info) or
             self.compare_volumes_from(container_info) or
             self.compare_environment(container_info) or
@@ -433,6 +439,17 @@ class DockerWorker(object):
         if new_labels != current_labels:
             return True
 
+    def compare_tmpfs(self, container_info):
+        new_tmpfs = self.generate_tmpfs()
+        current_tmpfs = container_info['HostConfig'].get('Tmpfs')
+        if not new_tmpfs:
+            new_tmpfs = []
+        if not current_tmpfs:
+            current_tmpfs = []
+
+        if set(current_tmpfs).symmetric_difference(set(new_tmpfs)):
+            return True
+
     def compare_volumes_from(self, container_info):
         new_vols_from = self.params.get('volumes_from')
         current_vols_from = container_info['HostConfig'].get('VolumesFrom')
@@ -637,6 +654,13 @@ class DockerWorker(object):
                 if self.check_container():
                     raise
 
+    def generate_tmpfs(self):
+        tmpfs = self.params.get('tmpfs')
+        if tmpfs:
+            # NOTE(mgoddard): Filter out any empty strings.
+            tmpfs = [t for t in tmpfs if t]
+        return tmpfs
+
     def generate_volumes(self):
         volumes = self.params.get('volumes')
         if not volumes:
@@ -711,6 +735,7 @@ class DockerWorker(object):
             'security_opt': self.params.get('security_opt'),
             'pid_mode': self.params.get('pid_mode'),
             'privileged': self.params.get('privileged'),
+            'tmpfs': self.generate_tmpfs(),
             'volumes_from': self.params.get('volumes_from')
         }
 
@@ -1066,6 +1091,7 @@ def generate_module():
         tls_cert=dict(required=False, type='str'),
         tls_key=dict(required=False, type='str'),
         tls_cacert=dict(required=False, type='str'),
+        tmpfs=dict(required=False, type='list'),
         volumes=dict(required=False, type='list'),
         volumes_from=dict(required=False, type='list'),
         dimensions=dict(required=False, type='dict', default=dict()),
diff --git a/releasenotes/notes/docker-tmpfs-2599b2785edeecd2.yaml b/releasenotes/notes/docker-tmpfs-2599b2785edeecd2.yaml
new file mode 100644
index 000000000..a82aac14b
--- /dev/null
+++ b/releasenotes/notes/docker-tmpfs-2599b2785edeecd2.yaml
@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Adds support to the ``kolla_docker`` module for creating ``tmpfs`` mounts
+    for containers.
diff --git a/tests/test_kolla_docker.py b/tests/test_kolla_docker.py
index c8dca3572..fb724aad8 100644
--- a/tests/test_kolla_docker.py
+++ b/tests/test_kolla_docker.py
@@ -88,6 +88,7 @@ class ModuleArgsTest(base.BaseTestCase):
             tls_cert=dict(required=False, type='str'),
             tls_key=dict(required=False, type='str'),
             tls_cacert=dict(required=False, type='str'),
+            tmpfs=dict(required=False, type='list'),
             volumes=dict(required=False, type='list'),
             volumes_from=dict(required=False, type='list'),
             dimensions=dict(required=False, type='dict', default=dict()),
@@ -136,6 +137,7 @@ FAKE_DATA = {
             'security_opt': None,
             'pid_mode': '',
             'privileged': False,
+            'tmpfs': None,
             'volumes_from': None,
             'restart_policy': 'unless-stopped',
             'restart_retries': 10},
@@ -276,7 +278,7 @@ class TestContainer(base.BaseTestCase):
             **{k: self.fake_data['params'][k] for k in expected_args})
         self.dw.dc.create_host_config.assert_called_with(
             cap_add=None, network_mode='host', ipc_mode=None,
-            pid_mode=None, volumes_from=None, blkio_weight=10,
+            pid_mode=None, tmpfs=None, volumes_from=None, blkio_weight=10,
             security_opt=None, privileged=None)
 
     def test_create_container_wrong_dimensions(self):
@@ -303,6 +305,25 @@ class TestContainer(base.BaseTestCase):
         self.dw.dc.create_container.assert_called_once_with(
             **{k: self.fake_data['params'][k] for k in expected_args})
 
+    def test_create_container_with_tmpfs(self):
+        self.fake_data['params']['tmpfs'] = ['/tmp']  # nosec: B108
+        self.dw = get_DockerWorker(self.fake_data['params'])
+        self.dw.dc.create_host_config = mock.MagicMock(
+            return_value=self.fake_data['params']['host_config'])
+        self.dw.create_container()
+        self.assertTrue(self.dw.changed)
+        self.assertEqual(['/tmp'],  # nosec: B108
+                         self.dw.dc.create_host_config.call_args[1]['tmpfs'])
+
+    def test_create_container_with_tmpfs_empty_string(self):
+        self.fake_data['params']['tmpfs'] = ['']
+        self.dw = get_DockerWorker(self.fake_data['params'])
+        self.dw.dc.create_host_config = mock.MagicMock(
+            return_value=self.fake_data['params']['host_config'])
+        self.dw.create_container()
+        self.assertTrue(self.dw.changed)
+        self.assertFalse(self.dw.dc.create_host_config.call_args[1]['tmpfs'])
+
     def test_start_container_without_pull(self):
         self.fake_data['params'].update({'auth_username': 'fake_user',
                                          'auth_password': 'fake_psw',
@@ -979,6 +1000,36 @@ class TestAttrComp(base.BaseTestCase):
             Labels={'kolla_version': '1.0.1'}))
         self.assertTrue(self.dw.compare_labels(container_info))
 
+    def test_compare_tmpfs_neg(self):
+        container_info = {'HostConfig': dict(Tmpfs=['foo'])}
+        self.dw = get_DockerWorker({'tmpfs': ['foo']})
+
+        self.assertFalse(self.dw.compare_tmpfs(container_info))
+
+    def test_compare_tmpfs_neg_empty_string(self):
+        container_info = {'HostConfig': dict()}
+        self.dw = get_DockerWorker({'tmpfs': ['']})
+
+        self.assertFalse(self.dw.compare_tmpfs(container_info))
+
+    def test_compare_tmpfs_pos_different(self):
+        container_info = {'HostConfig': dict(Tmpfs=['foo'])}
+        self.dw = get_DockerWorker({'tmpfs': ['bar']})
+
+        self.assertTrue(self.dw.compare_tmpfs(container_info))
+
+    def test_compare_tmpfs_pos_empty_new(self):
+        container_info = {'HostConfig': dict(Tmpfs=['foo'])}
+        self.dw = get_DockerWorker({})
+
+        self.assertTrue(self.dw.compare_tmpfs(container_info))
+
+    def test_compare_tmpfs_pos_empty_current(self):
+        container_info = {'HostConfig': dict()}
+        self.dw = get_DockerWorker({'tmpfs': ['bar']})
+
+        self.assertTrue(self.dw.compare_tmpfs(container_info))
+
     def test_compare_volumes_from_neg(self):
         container_info = {'HostConfig': dict(VolumesFrom=['777f7dc92da7'])}
         self.dw = get_DockerWorker({'volumes_from': ['777f7dc92da7']})