Add podman logout module (#134)

* Add podman logout module
* Add more tests
* Fix output string comparison (due to podman inconsistency)
* Fix copy and paste error
* Use full module path and name
Fix #94

plugins/modules/podman_logout.py

@@ -0,0 +1,126 @@
+#!/usr/bin/python
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import absolute_import, division, print_function
+__metaclass__ = type
+
+DOCUMENTATION = r'''
+module: podman_logout
+author:
+  - "Clemens Lange (@clelange)"
+short_description: Log out of a container registry using podman
+notes: []
+description:
+  - Log out of a container registry server using the podman logout command
+    by deleting the cached credentials stored in the `auth.json` file.
+    If the registry is not specified, the first registry under
+    `[registries.search]` from `registries.conf `will be used. The path of
+    the authentication file can be overridden by the user by setting the
+    `authfile` flag. The default path used is
+    `${XDG_RUNTIME_DIR}/containers/auth.json`.
+    All the cached credentials can be removed by setting the `all` flag.
+requirements:
+  - "Podman installed on host"
+options:
+  registry:
+    description:
+      - Registry server. If the registry is not specified,
+        the first registry under `[registries.search]` from
+        `registries.conf` will be used.
+    type: str
+  authfile:
+    description:
+      - Path of the authentication file. Default is
+        ``${XDG_RUNTIME_DIR}/containers/auth.json``
+        You can also override the default path of the authentication
+        file by setting the ``REGISTRY_AUTH_FILE`` environment
+        variable. ``export REGISTRY_AUTH_FILE=path``
+    type: path
+  all:
+    description:
+      - Remove the cached credentials for all registries in the auth file
+    type: bool
+  executable:
+    description:
+      - Path to C(podman) executable if it is not in the C($PATH) on the
+        machine running C(podman)
+    default: 'podman'
+    type: str
+'''
+
+EXAMPLES = r"""
+- name: Log out of default registry
+  podman_logout:
+
+- name: Log out of quay.io
+  podman_logout:
+    registry: quay.io
+
+- name: Log out of all registries in auth file
+  podman_logout:
+    all: yes
+
+- name: Log out of all registries in specified auth file
+  podman_logout:
+    authfile: $HOME/.docker/config.json
+    all: yes
+"""
+# noqa: F402
+
+import json  # noqa: F402
+from ansible.module_utils.basic import AnsibleModule
+
+
+def logout(module, executable, registry, authfile, all_registries):
+    command = [executable, 'logout']
+    changed = False
+    if authfile:
+        command.extend(['--authfile', authfile])
+    if registry:
+        command.append(registry)
+    if all_registries:
+        command.append("--all")
+    rc, out, err = module.run_command(command)
+    if rc != 0:
+        if 'Error: Not logged into' not in err:
+            module.fail_json(msg="Unable to gather info for %s: %s" % (registry, err))
+    else:
+        # If the command is successful, we managed to log out
+        # Mind: This also applied if --all flag is used, while in this case
+        # there is no check whether one has been logged into any registry
+        changed = True
+    return changed, out, err
+
+
+def main():
+    module = AnsibleModule(
+        argument_spec=dict(
+            executable=dict(type='str', default='podman'),
+            registry=dict(type='str'),
+            authfile=dict(type='path'),
+            all=dict(type='bool'),
+        ),
+        supports_check_mode=True,
+        mutually_exclusive=(
+            ['registry', 'all'],
+        ),
+    )
+
+    registry = module.params['registry']
+    authfile = module.params['authfile']
+    all_registries = module.params['all']
+    executable = module.get_bin_path(module.params['executable'], required=True)
+
+    changed, out, err = logout(module, executable, registry, authfile, all_registries)
+
+    results = {
+        "changed": changed,
+        "stdout": out,
+        "stderr": err,
+    }
+
+    module.exit_json(**results)
+
+
+if __name__ == '__main__':
+    main()