Support health check for Docker containers

The docker has supported healthcheck. It is useful for application
container.
Zun may integration these options.

  --health-cmd Command to run to check health
  --health-interval Time between running the check
  --health-retries Consecutive failures needed to report unhealthy
  --health-timeout Maximum time to allow one check to run
  In zun, the four parameter are cmd, interval, retries, timeout.

Partial-Implements: blueprint support-healthycheck

Change-Id: I1f4f6a5536a33ecb9ac9c032b119a9349e3616ee

zun/api/controllers/v1/containers.py

@@ -355,6 +355,12 @@ class ContainersController(base.Controller):
         pci_req = self._create_pci_requests_for_sriov_ports(context,
                                                             requested_networks)
 
+        healthcheck = container_dict.pop('healthcheck', {})
+        if healthcheck:
+            api_utils.version_check('healthcheck', '1.22')
+            healthcheck['test'] = healthcheck.pop('cmd', '')
+            container_dict['healthcheck'] = healthcheck
+
         mounts = container_dict.pop('mounts', [])
         if mounts:
             api_utils.version_check('mounts', '1.11')

zun/api/controllers/v1/schemas/containers.py

@@ -38,6 +38,7 @@ _legacy_container_properties = {
     'availability_zone': parameter_types.availability_zone,
     'auto_heal': parameter_types.boolean,
     'privileged': parameter_types.boolean,
+    'healthcheck': parameter_types.healthcheck,
 }
 
 legacy_container_create = {

zun/api/controllers/v1/schemas/parameter_types.py

@@ -172,6 +172,30 @@ availability_zone = {
     'maxLength': 255,
 }
 
+healthcheck = {
+    'type': ['object', 'null'],
+    'items': {
+        'type': 'object',
+        'properties': {
+            'cmd': {
+                'type': ['string'],
+                'minLength': 1,
+                'maxLength': 255
+            },
+            'interval': {
+                'type': ['integer', 'null']
+            },
+            'retries': {
+                'type': ['integer', 'null']
+            },
+            'timeout': {
+                'type': ['integer', 'null']
+            }
+        },
+        'additionalProperties': False
+    }
+}
+
 mounts = {
     'type': ['array', 'null'],
     'items': {

zun/api/controllers/v1/views/containers_view.py

@@ -48,6 +48,7 @@ _basic_keys = (
     'disk',
     'auto_heal',
     'privileged',
+    'healthcheck',
 )
 
 

zun/api/controllers/versions.py

@@ -51,13 +51,14 @@ REST_API_VERSION_HISTORY = """REST API Version History:
     * 1.16 - Modify restart_policy to capsule spec content
     * 1.17 - Add support for detaching ports
     * 1.18 - Modify the response of network list
-    * 1.19 - Intoduce container resize API
+    * 1.19 - Introduce container resize API
     * 1.20 - Convert type of 'command' from string to list
     * 1.21 - Add support privileged
+    * 1.22 - Add healthcheck to container create
 """
 
 BASE_VER = '1.1'
-CURRENT_MAX_VER = '1.21'
+CURRENT_MAX_VER = '1.22'
 
 
 class Version(object):

zun/api/rest_api_version_history.rst

@@ -177,3 +177,9 @@ user documentation.
 ----
 
   Support privileged container
+
+1.22
+----
+
+  Add healthcheck to container create
+

zun/container/docker/driver.py

@@ -301,6 +301,18 @@ class DockerDriver(driver.ContainerDriver):
             if container.disk:
                 disk_size = str(container.disk) + 'G'
                 host_config['storage_opt'] = {'size': disk_size}
+            # The time unit in docker of heath checking is us, and the unit
+            # of interval and timeout is seconds.
+            if container.healthcheck:
+                healthcheck = {}
+                healthcheck['test'] = container.healthcheck.get('test', '')
+                interval = container.healthcheck.get('interval', 0)
+                healthcheck['interval'] = interval * 10 ** 9
+                healthcheck['retries'] = int(container.healthcheck.
+                                             get('retries', 0))
+                timeout = container.healthcheck.get('timeout', 0)
+                healthcheck['timeout'] = timeout * 10 ** 9
+                kwargs['healthcheck'] = healthcheck
 
             kwargs['host_config'] = docker.create_host_config(**host_config)
             if image['tag']:

zun/db/sqlalchemy/alembic/versions/2fb377a5a519_add_healthcheck_to_container.py

@@ -0,0 +1,36 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""add healthcheck to containers
+
+Revision ID: 2fb377a5a519
+Revises: 105626c4f972
+Create Date: 2018-05-03 11:27:00.722445
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '2fb377a5a519'
+down_revision = '105626c4f972'
+branch_labels = None
+depends_on = None
+
+from alembic import op
+import sqlalchemy as sa
+import zun
+
+
+def upgrade():
+    with op.batch_alter_table('container', schema=None) as batch_op:
+        batch_op.add_column(sa.Column(
+            'healthcheck', zun.db.sqlalchemy.models.JSONEncodedDict(),
+            nullable=True))

zun/db/sqlalchemy/models.py

@@ -171,6 +171,7 @@ class Container(Base):
                         ForeignKey('capsule.id', ondelete='CASCADE'))
     started_at = Column(DateTime)
     privileged = Column(Boolean, default=False)
+    healthcheck = Column(JSONEncodedDict)
 
 
 class VolumeMapping(Base):

zun/objects/container.py

@@ -64,7 +64,8 @@ class Container(base.ZunPersistentObject, base.ZunObject):
     # Version 1.32: Add 'exec_instances' attribute
     # Version 1.33: Change 'command' to List type
     # Version 1.34: Add privileged to container
-    VERSION = '1.34'
+    # Version 1.35: Add 'healthcheck' attribute
+    VERSION = '1.35'
 
     fields = {
         'id': fields.IntegerField(),
@@ -107,6 +108,7 @@ class Container(base.ZunPersistentObject, base.ZunObject):
         'exec_instances': fields.ListOfObjectsField('ExecInstance',
                                                     nullable=True),
         'privileged': fields.BooleanField(nullable=True),
+        'healthcheck': z_fields.JsonField(nullable=True),
     }
 
     @staticmethod

zun/tests/unit/api/base.py

@@ -26,7 +26,7 @@ from zun.tests.unit.db import base
 
 
 PATH_PREFIX = '/v1'
-CURRENT_VERSION = "container 1.21"
+CURRENT_VERSION = "container 1.22"
 
 
 class FunctionalTest(base.DbTestCase):

zun/tests/unit/api/controllers/test_root.py

@@ -28,7 +28,7 @@ class TestRootController(api_base.FunctionalTest):
             'default_version':
             {'id': 'v1',
              'links': [{'href': 'http://localhost/v1/', 'rel': 'self'}],
-             'max_version': '1.21',
+             'max_version': '1.22',
              'min_version': '1.1',
              'status': 'CURRENT'},
             'description': 'Zun is an OpenStack project which '
@@ -37,7 +37,7 @@ class TestRootController(api_base.FunctionalTest):
             'versions': [{'id': 'v1',
                           'links': [{'href': 'http://localhost/v1/',
                                      'rel': 'self'}],
-                          'max_version': '1.21',
+                          'max_version': '1.22',
                           'min_version': '1.1',
                           'status': 'CURRENT'}]}
 

zun/tests/unit/api/controllers/v1/test_containers.py

@@ -121,6 +121,16 @@ class TestContainerController(api_base.FunctionalTest):
                       params=params, content_type='application/json',
                       headers=headers)
 
+    def test_run_container_healthcheck_wrong_value(self):
+        params = ('{"name": "MyDocker", "image": "ubuntu",'
+                  '"command": ["env"], "memory": "512",'
+                  '"environment": {"key1": "val1", "key2": "val2"},'
+                  '"healthcheck": "test"}')
+        with self.assertRaisesRegex(AppError,
+                                    "Invalid input for field"):
+            self.post('/v1/containers?run=true',
+                      params=params, content_type='application/json')
+
     @patch('zun.network.neutron.NeutronAPI.get_available_network')
     @patch('zun.compute.api.API.container_create')
     @patch('zun.compute.api.API.image_search')

zun/tests/unit/container/docker/test_docker_driver.py

@@ -117,6 +117,7 @@ class TestDockerDriver(base.DriverTestCase):
         image = {'path': '', 'image': '', 'repo': 'test', 'tag': 'test'}
         mock_container = self.mock_default_container
         mock_container.status = 'Creating'
+        mock_container.healthcheck = {}
         networks = [{'network': 'fake-network'}]
         volumes = []
         fake_port = {'mac_address': 'fake_mac'}
@@ -183,6 +184,7 @@ class TestDockerDriver(base.DriverTestCase):
         image = {'path': '', 'image': '', 'repo': 'test', 'tag': 'test'}
         mock_container = self.mock_default_container
         mock_container.status = 'Creating'
+        mock_container.healthcheck = {}
         networks = [{'network': 'fake-network'}]
         volumes = []
         fake_port = {'mac_address': 'fake_mac'}
@@ -251,6 +253,7 @@ class TestDockerDriver(base.DriverTestCase):
         image = {'path': '', 'image': '', 'repo': 'test', 'tag': 'test'}
         mock_container = self.mock_default_container
         mock_container.status = 'Creating'
+        mock_container.healthcheck = {}
         mock_container.runtime = None
         networks = [{'network': 'fake-network'}]
         volumes = []

zun/tests/unit/db/utils.py

@@ -103,6 +103,10 @@ def get_test_container(**kwargs):
         'capsule_id': kwargs.get('capsule_id', 42),
         'started_at': kwargs.get('started_at'),
         'privileged': kwargs.get('privileged', False),
+        'healthcheck': kwargs.get('healthcheck',
+                                  {"retries": "2", "timeout": 3,
+                                   "test": "stat /etc/passwd || exit 1",
+                                   "interval": 3}),
     }
 
 

zun/tests/unit/objects/test_objects.py

@@ -344,7 +344,7 @@ class TestObject(test_base.TestCase, _TestObject):
 # For more information on object version testing, read
 # https://docs.openstack.org/zun/latest/
 object_data = {
-    'Container': '1.34-22c46c6ae571b83295c3dac74fe8772f',
+    'Container': '1.35-7cadf071bb6865a6da6b7be581ce76f6',
     'VolumeMapping': '1.1-50df6202f7846a136a91444c38eba841',
     'Image': '1.1-330e6205c80b99b59717e1cfc6a79935',
     'MyObj': '1.0-34c4b1aadefd177b13f9a2f894cc23cd',