Generate systemd service files for containers (#298)

plugins/module_utils/podman/podman_container_lib.py

@@ -54,6 +54,7 @@ ARGUMENTS_SPEC_CONTAINER = dict(
                 'exposed', 'exposed_ports']),
     force_restart=dict(type='bool', default=False,
                        aliases=['restart']),
+    generate_systemd=dict(type='dict', default={}),
     gidmap=dict(type='list', elements='str'),
     group_add=dict(type='list', elements='str', aliases=['groups']),
     healthcheck=dict(type='str'),
@@ -1510,6 +1511,56 @@ class PodmanManager:
         self.container = PodmanContainer(
             self.module, self.name, self.module_params)
 
+    def generate_systemd(self):
+        """Generate systemd unit file."""
+        command = [self.module_params['executable'], 'generate', 'systemd',
+                   self.name, '--format', 'json']
+        sysconf = self.module_params['generate_systemd']
+        empty = {'name': '', 'text': ''}
+        if sysconf.get('restart_policy'):
+            if sysconf.get('restart_policy') not in [
+                "no", "on-success", "on-failure", "on-abnormal", "on-watchdog",
+                    "on-abort", "always"]:
+                self.module.fail_json(
+                    'Restart policy for systemd unit file is "%s" and must be one of: '
+                    '"no", "on-success", "on-failure", "on-abnormal", "on-watchdog", "on-abort", or "always"' %
+                    sysconf.get('restart_policy'))
+            command.extend([
+                '--restart-policy',
+                sysconf['restart_policy']])
+        if sysconf.get('time'):
+            command.extend(['--time', str(sysconf['time'])])
+        if sysconf.get('no_header'):
+            command.extend(['--no-header'])
+        if sysconf.get('names', True):
+            command.extend(['--name'])
+        if sysconf.get('container_prefix'):
+            command.extend(['--container-prefix=%s' % sysconf['container_prefix']])
+        if sysconf.get('pod_prefix'):
+            command.extend(['--pod-prefix=%s' % sysconf['pod_prefix']])
+        if sysconf.get('separator'):
+            command.extend(['--separator=%s' % sysconf['separator']])
+        if self.module.params['debug'] or self.module_params['debug']:
+            self.module.log("PODMAN-CONTAINER-DEBUG: systemd command: %s" % " ".join(command))
+        rc, systemd, err = self.module.run_command(command)
+        if rc != 0:
+            self.module.log(
+                "PODMAN-CONTAINER-DEBUG: Error generating systemd: %s" % err)
+            return empty
+        else:
+            try:
+                systemd_text = list(json.loads(systemd).values())[0]
+                systemd_name = list(json.loads(systemd).keys())[0]
+                if sysconf.get('file'):
+                    with open(sysconf['file'], 'w') as f:
+                        f.write(systemd_text)
+                return {'name': systemd_name,
+                        'text': systemd_text}
+            except Exception as e:
+                self.module.log(
+                    "PODMAN-CONTAINER-DEBUG: Error writing systemd: %s" % e)
+                return empty
+
     def update_container_result(self, changed=True):
         """Inspect the current container, update results with last info, exit.
 
@@ -1526,6 +1577,8 @@ class PodmanManager:
             self.results.update({'diff': self.container.diff})
         if self.module.params['debug'] or self.module_params['debug']:
             self.results.update({'podman_version': self.container.version})
+        self.results.update(
+            {'podman_systemd': self.generate_systemd()})
 
     def make_started(self):
         """Run actions if desired state is 'started'."""

plugins/modules/podman_container.py

@@ -291,6 +291,65 @@ options:
     default: False
     aliases:
       - restart
+  generate_systemd:
+    description:
+      - Generate systemd unit file for container.
+    type: dict
+    default: {}
+    suboptions:
+      file:
+        description:
+          - Specify a path to the service file to be generated.
+        type: str
+        required: false
+      restart_policy:
+        description:
+          - Specify a restart policy for the service.  The restart-policy must be one of
+            "no", "on-success", "on-failure", "on-abnormal", "on-watchdog", "on-abort", or "always".
+            The default policy is "on-failure".
+        type: str
+        required: false
+        choices:
+            - 'no'
+            - 'on-success'
+            - 'on-failure'
+            - 'on-abnormal'
+            - 'on-watchdog'
+            - 'on-abort'
+            - 'always'
+      time:
+        description:
+          - Override the default stop timeout for the container with the given value.
+        type: int
+        required: false
+      no_header:
+        description:
+          - Do not generate the header including meta data such as the Podman version and the timestamp.
+            From podman version 3.1.0.
+        type: bool
+        default: false
+      names:
+        description:
+          - Use names of the containers for the start, stop, and description in the unit file.
+            Default is true.
+        type: bool
+        default: true
+      container_prefix:
+        description:
+          - Set the systemd unit name prefix for containers. The default is "container".
+        type: str
+        required: false
+      pod_prefix:
+        description:
+          - Set the systemd unit name prefix for pods. The default is "pod".
+        type: str
+        required: false
+      separator:
+        description:
+          - Set the systemd unit name separator between the name/id of a
+            container/pod and the prefix. The default is "-" (dash).
+        type: str
+        required: false
   gidmap:
     description:
       - Run the container in a new user namespace using the supplied mapping.

tests/integration/targets/podman_container/tasks/main.yml

@@ -7,7 +7,9 @@
       loop:
         - "alpine:3.7"
         - "container"
+        - "container1"
         - "container2"
+        - "testidem-pod"
 
     - name: Test no image with default action
       containers.podman.podman_container:
@@ -531,13 +533,42 @@
       assert:
         that:
           - idem4 is changed
+          - idem4.podman_systemd.name != ''
+          - idem4.podman_systemd.text != ''
+
+    - name: Run container with systemd generation parameters
+      containers.podman.podman_container:
+        name: container1
+        image: alpine
+        state: started
+        command: sleep 20m
+        generate_systemd:
+          file: /tmp/my.service
+          restart_policy: always
+          time: 120
+          no_header: true
+          names: true
+          pod_prefix: whocares
+          separator: zzzz
+          container_prefix: contain
+      register: system1
+
+    - name: Check that container is recreated when changed
+      assert:
+        that:
+          - system1.podman_systemd.name == 'containzzzzcontainer1'
+          - system1.podman_systemd.text != ''
+          - "'stop -t 120 container1' in system1.podman_systemd.text"
+          - "'Restart=always' in system1.podman_systemd.text"
+          - "'autogenerated by Podman' not in system1.podman_systemd.text"
+
+  always:
 
     - name: Remove container
       containers.podman.podman_container:
         name: testidem-pod
         state: absent
 
-  always:
     - name: Delete all container leftovers from tests
       containers.podman.podman_container:
         name: "{{ item }}"
@@ -545,7 +576,10 @@
       loop:
         - "alpine:3.7"
         - "container"
+        - "container1"
         - "container2"
+        - "testidem-pod"
 
     - name: Remove pod
       shell: podman pod rm -f testidempod
+      ignore_errors: true