snap - revamp + implementing enabled/disabled states (#2411)

* revamp of snap module

* added changelog fragment

* fixed description

* Update changelogs/fragments/2411-snap-revamp-enabled-disabled-states.yml

Co-authored-by: Felix Fontein <felix@fontein.de>

Co-authored-by: Felix Fontein <felix@fontein.de>

changelogs/fragments/2411-snap-revamp-enabled-disabled-states.yml

@@ -0,0 +1,2 @@
+minor_changes:
+  - snap - added ``enabled`` and ``disabled`` states (https://github.com/ansible-collections/community.general/issues/1990).

plugins/modules/packaging/os/snap.py

@@ -31,7 +31,7 @@ options:
             - Desired state of the package.
         required: false
         default: present
-        choices: [ absent, present ]
+        choices: [ absent, present, enabled, disabled ]
         type: str
     classic:
         description:
@@ -105,151 +105,184 @@ snaps_removed:
     returned: When any snaps have been removed
 '''
 
-import operator
 import re
 
-from ansible.module_utils.basic import AnsibleModule
+from ansible_collections.community.general.plugins.module_utils.module_helper import (
+    CmdStateModuleHelper, ArgFormat, ModuleHelperException
+)
 
 
-def validate_input_snaps(module):
+__state_map = dict(
-    """Ensure that all exist."""
+    present='install',
-    for snap_name in module.params['name']:
+    absent='remove',
-        if not snap_exists(module, snap_name):
+    info='info',  # not public
-            module.fail_json(msg="No snap matching '%s' available." % snap_name)
+    list='list',  # not public
+    enabled='enable',
+    disabled='disable',
+)
 
 
-def snap_exists(module, snap_name):
+def _state_map(value):
-    snap_path = module.get_bin_path("snap", True)
+    return __state_map[value]
-    cmd_parts = [snap_path, 'info', snap_name]
-    cmd = ' '.join(cmd_parts)
-    rc, out, err = module.run_command(cmd, check_rc=False)
-
-    return rc == 0
 
 
-def is_snap_installed(module, snap_name):
+class Snap(CmdStateModuleHelper):
-    snap_path = module.get_bin_path("snap", True)
+    __disable_re = re.compile(r'(?:\S+\s+){5}(?P<notes>\S+)')
-    cmd_parts = [snap_path, 'list', snap_name]
+    module = dict(
-    cmd = ' '.join(cmd_parts)
+        argument_spec={
-    rc, out, err = module.run_command(cmd, check_rc=False)
+            'name': dict(type='list', elements='str', required=True),
+            'state': dict(type='str', required=False, default='present',
+                          choices=['absent', 'present', 'enabled', 'disabled']),
+            'classic': dict(type='bool', required=False, default=False),
+            'channel': dict(type='str', required=False, default='stable'),
+        },
+        supports_check_mode=True,
+    )
+    command = "snap"
+    command_args_formats = dict(
+        actionable_snaps=dict(fmt=lambda v: v),
+        state=dict(fmt=_state_map),
+        classic=dict(fmt="--classic", style=ArgFormat.BOOLEAN),
+        channel=dict(fmt=lambda v: [] if v == 'stable' else ['--channel', '{0}']),
+    )
+    check_rc = False
 
-    return rc == 0
+    @staticmethod
+    def _first_non_zero(a):
+        for elem in a:
+            if elem != 0:
+                return elem
 
+        return 0
 
-def get_snap_for_action(module):
+    def _run_multiple_commands(self, commands):
-    """Construct a list of snaps to use for current action."""
+        outputs = [(c,) + self.run_command(params=c) for c in commands]
-    snaps = module.params['name']
+        results = ([], [], [], [])
+        for output in outputs:
+            for i in range(4):
+                results[i].append(output[i])
 
-    is_present_state = module.params['state'] == 'present'
+        return [
-    negation_predicate = operator.not_ if is_present_state else bool
+            '; '.join(results[0]),
+            self._first_non_zero(results[1]),
+            '\n'.join(results[2]),
+            '\n'.join(results[3]),
+        ]
 
-    def predicate(s):
+    def snap_exists(self, snap_name):
-        return negation_predicate(is_snap_installed(module, s))
+        return 0 == self.run_command(params=[{'state': 'info'}, {'name': [snap_name]}])[0]
 
-    return [s for s in snaps if predicate(s)]
+    def is_snap_installed(self, snap_name):
+        return 0 == self.run_command(params=[{'state': 'list'}, {'name': [snap_name]}])[0]
 
+    def is_snap_enabled(self, snap_name):
+        rc, out, err = self.run_command(params=[{'state': 'list'}, {'name': [snap_name]}])
+        if rc != 0:
+            return None
+        result = out.splitlines()[1]
+        match = self.__disable_re.match(result)
+        if not match:
+            raise ModuleHelperException(msg="Unable to parse 'snap list {0}' output:\n{1}".format(snap_name, out))
+        notes = match.group('notes')
+        return "disabled" not in notes.split(',')
 
-def get_base_cmd_parts(module):
+    def validate_input_snaps(self):
-    action_map = {
+        """Ensure that all exist."""
-        'present': 'install',
+        for snap_name in self.vars.name:
-        'absent': 'remove',
+            if not self.snap_exists(snap_name):
-    }
+                raise ModuleHelperException(msg="No snap matching '%s' available." % snap_name)
 
-    state = module.params['state']
+    def state_present(self):
+        self.validate_input_snaps()  # if snap doesnt exist, it will explode when trying to install
+        self.vars.meta('classic').set(output=True)
+        self.vars.meta('channel').set(output=True)
+        actionable_snaps = [s for s in self.vars.name if self.is_snap_installed(s)]
+        if not actionable_snaps:
+            return
+        self.changed = True
+        self.vars.snaps_installed = actionable_snaps
+        if self.module.check_mode:
+            return
+        params = ['classic', 'channel', 'state']  # get base cmd parts
+        has_one_pkg_params = bool(self.vars.classic) or self.vars.channel != 'stable'
+        has_multiple_snaps = len(actionable_snaps) > 1
+        if has_one_pkg_params and has_multiple_snaps:
+            commands = [params + [s] for s in actionable_snaps]
+        else:
+            commands = [params + actionable_snaps]
+        self.vars.cmd, rc, out, err = self._run_multiple_commands(commands)
+        if rc == 0:
+            return
 
-    classic = ['--classic'] if module.params['classic'] else []
+        classic_snap_pattern = re.compile(r'^error: This revision of snap "(?P<package_name>\w+)"'
-    channel = ['--channel', module.params['channel']] if module.params['channel'] and module.params['channel'] != 'stable' else []
+                                          r' was published using classic confinement')
+        match = classic_snap_pattern.match(err)
+        if match:
+            err_pkg = match.group('package_name')
+            msg = "Couldn't install {name} because it requires classic confinement".format(name=err_pkg)
+        else:
+            msg = "Ooops! Snap installation failed while executing '{cmd}', please examine logs and " \
+                  "error output for more details.".format(cmd=self.vars.cmd)
+        raise ModuleHelperException(msg=msg)
 
-    snap_path = module.get_bin_path("snap", True)
+    def state_absent(self):
-    snap_action = action_map[state]
+        self.validate_input_snaps()  # if snap doesnt exist, it will be absent by definition
+        actionable_snaps = [s for s in self.vars.name if not self.is_snap_installed(s)]
+        if not actionable_snaps:
+            return
+        self.changed = True
+        self.vars.snaps_removed = actionable_snaps
+        if self.module.check_mode:
+            return
+        params = ['classic', 'channel', 'state']  # get base cmd parts
+        commands = [params + actionable_snaps]
+        self.vars.cmd, rc, out, err = self._run_multiple_commands(commands)
+        if rc == 0:
+            return
+        msg = "Ooops! Snap removal failed while executing '{cmd}', please examine logs and " \
+              "error output for more details.".format(cmd=self.vars.cmd)
+        raise ModuleHelperException(msg=msg)
 
-    cmd_parts = [snap_path, snap_action]
+    def state_enabled(self):
-    if snap_action == 'install':
+        self.validate_input_snaps()
-        cmd_parts += classic + channel
+        actionable_snaps = [s for s in self.vars.name if self.is_snap_enabled(s) is False]
+        if not actionable_snaps:
+            return
+        self.changed = True
+        self.vars.snaps_enabled = actionable_snaps
+        if self.module.check_mode:
+            return
+        params = ['classic', 'channel', 'state']  # get base cmd parts
+        commands = [params + actionable_snaps]
+        self.vars.cmd, rc, out, err = self._run_multiple_commands(commands)
+        if rc == 0:
+            return
+        msg = "Ooops! Snap enabling failed while executing '{cmd}', please examine logs and " \
+              "error output for more details.".format(cmd=self.vars.cmd)
+        raise ModuleHelperException(msg=msg)
 
-    return cmd_parts
+    def state_disabled(self):
-
+        self.validate_input_snaps()
-
+        actionable_snaps = [s for s in self.vars.name if self.is_snap_enabled(s) is True]
-def get_cmd_parts(module, snap_names):
+        if not actionable_snaps:
-    """Return list of cmds to run in exec format."""
+            return
-    is_install_mode = module.params['state'] == 'present'
+        self.changed = True
-    has_multiple_snaps = len(snap_names) > 1
+        self.vars.snaps_enabled = actionable_snaps
-
+        if self.module.check_mode:
-    cmd_parts = get_base_cmd_parts(module)
+            return
-    has_one_pkg_params = '--classic' in cmd_parts or '--channel' in cmd_parts
+        params = ['classic', 'channel', 'state']  # get base cmd parts
-
+        commands = [params + actionable_snaps]
-    if not (is_install_mode and has_one_pkg_params and has_multiple_snaps):
+        self.vars.cmd, rc, out, err = self._run_multiple_commands(commands)
-        return [cmd_parts + snap_names]
+        if rc == 0:
-
+            return
-    return [cmd_parts + [s] for s in snap_names]
+        msg = "Ooops! Snap disabling failed while executing '{cmd}', please examine logs and " \
-
+              "error output for more details.".format(cmd=self.vars.cmd)
-
+        raise ModuleHelperException(msg=msg)
-def run_cmd_for(module, snap_names):
-    cmds_parts = get_cmd_parts(module, snap_names)
-    cmd = '; '.join(' '.join(c) for c in cmds_parts)
-    cmd = 'sh -c "{0}"'.format(cmd)
-
-    # Actually execute the snap command
-    return (cmd, ) + module.run_command(cmd, check_rc=False)
-
-
-def execute_action(module):
-    is_install_mode = module.params['state'] == 'present'
-    exit_kwargs = {
-        'classic': module.params['classic'],
-        'channel': module.params['channel'],
-    } if is_install_mode else {}
-
-    actionable_snaps = get_snap_for_action(module)
-    if not actionable_snaps:
-        module.exit_json(changed=False, **exit_kwargs)
-
-    changed_def_args = {
-        'changed': True,
-        'snaps_{result}'.
-        format(result='installed' if is_install_mode
-               else 'removed'): actionable_snaps,
-    }
-
-    if module.check_mode:
-        module.exit_json(**dict(changed_def_args, **exit_kwargs))
-
-    cmd, rc, out, err = run_cmd_for(module, actionable_snaps)
-    cmd_out_args = {
-        'cmd': cmd,
-        'rc': rc,
-        'stdout': out,
-        'stderr': err,
-    }
-
-    if rc == 0:
-        module.exit_json(**dict(changed_def_args, **dict(cmd_out_args, **exit_kwargs)))
-    else:
-        msg = "Ooops! Snap installation failed while executing '{cmd}', please examine logs and error output for more details.".format(cmd=cmd)
-        if is_install_mode:
-            m = re.match(r'^error: This revision of snap "(?P<package_name>\w+)" was published using classic confinement', err)
-            if m is not None:
-                err_pkg = m.group('package_name')
-                msg = "Couldn't install {name} because it requires classic confinement".format(name=err_pkg)
-        module.fail_json(msg=msg, **dict(cmd_out_args, **exit_kwargs))
 
 
 def main():
-    module_args = {
+    snap = Snap()
-        'name': dict(type='list', elements='str', required=True),
+    snap.run()
-        'state': dict(type='str', required=False, default='present', choices=['absent', 'present']),
-        'classic': dict(type='bool', required=False, default=False),
-        'channel': dict(type='str', required=False, default='stable'),
-    }
-    module = AnsibleModule(
-        argument_spec=module_args,
-        supports_check_mode=True,
-    )
-
-    validate_input_snaps(module)
-
-    # Apply changes to the snaps
-    execute_action(module)
 
 
 if __name__ == '__main__':