feat: dokku_checks module (#136)

Add ` dokku_checks` module that allows disabling the zero-downtime checks for dokku apps.

Note: This module currently only allows to disable or enable *all* checks of a given app.
It is not suitable for managing apps where checks should be disabled only for individual processes.

Co-authored-by: Leopold Talirz <[email protected]>

README.md

@@ -245,6 +245,31 @@ Manages ssl configuration for an app.
     state: absent
 ```
 
+### dokku_checks
+
+Manage the Zero Downtime checks for a dokku app
+
+#### Parameters
+
+|Parameter|Choices/Defaults|Comments|
+|---------|----------------|--------|
+|app<br /><sup>*required*</sup>||The name of the app|
+|state|*Choices:* <ul><li>**present** (default)</li><li>absent</li></ul>|The state of the checks functionality|
+
+#### Example
+
+```yaml
+- name: Disable the zero downtime deployment
+  dokku_checks:
+    app: hello-world
+    state: absent
+
+- name: Re-enable the zero downtime deployment (enabled by default)
+  dokku_checks:
+    app: hello-world
+    state: present
+```
+
 ### dokku_clone
 
 Clone a git repository and deploy app.

library/dokku_checks.py

@@ -0,0 +1,133 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+import subprocess
+
+from ansible.module_utils.basic import AnsibleModule
+from ansible.module_utils.dokku_utils import subprocess_check_output
+
+DOCUMENTATION = """
+---
+module: dokku_checks
+short_description: Manage the Zero Downtime checks for a dokku app
+options:
+  app:
+    description:
+      - The name of the app
+    required: True
+    default: null
+    aliases: []
+  state:
+    description:
+      - The state of the checks functionality
+    required: False
+    default: present
+    choices: [ "present", "absent" ]
+    aliases: []
+author: Simo Aleksandrov
+"""
+
+EXAMPLES = """
+- name: Disable the zero downtime deployment
+  dokku_checks:
+    app: hello-world
+    state: absent
+
+- name: Re-enable the zero downtime deployment (enabled by default)
+  dokku_checks:
+    app: hello-world
+    state: present
+"""
+
+
+def dokku_checks_enabled(data):
+    command = "dokku --quiet checks:report {0}"
+    response, error = subprocess_check_output(command.format(data["app"]))
+
+    if error:
+        return None, error
+
+    report = response[0].split(":")[1]
+    return report.strip() != "_all_", error
+
+
+def dokku_checks_present(data):
+    is_error = True
+    has_changed = False
+    meta = {"present": False}
+
+    enabled, error = dokku_checks_enabled(data)
+    if error:
+        meta["error"] = error
+        return (is_error, has_changed, meta)
+
+    if enabled:
+        is_error = False
+        meta["present"] = True
+        return (is_error, has_changed, meta)
+
+    command = "dokku --quiet checks:enable {0}".format(data["app"])
+    try:
+        subprocess.check_call(command, shell=True)
+        is_error = False
+        has_changed = True
+        meta["present"] = True
+    except subprocess.CalledProcessError as e:
+        meta["error"] = str(e)
+
+    return (is_error, has_changed, meta)
+
+
+def dokku_checks_absent(data=None):
+    is_error = True
+    has_changed = False
+    meta = {"present": True}
+
+    enabled, error = dokku_checks_enabled(data)
+    if error:
+        meta["error"] = error
+        return (is_error, has_changed, meta)
+
+    if enabled is False:
+        is_error = False
+        meta["present"] = False
+        return (is_error, has_changed, meta)
+
+    command = "dokku --quiet checks:disable {0}".format(data["app"])
+    try:
+        subprocess.check_call(command, shell=True)
+        is_error = False
+        has_changed = True
+        meta["present"] = False
+    except subprocess.CalledProcessError as e:
+        meta["error"] = str(e)
+
+    return (is_error, has_changed, meta)
+
+
+def main():
+    fields = {
+        "app": {"required": True, "type": "str"},
+        "state": {
+            "required": False,
+            "default": "present",
+            "choices": ["present", "absent"],
+            "type": "str",
+        },
+    }
+    choice_map = {
+        "present": dokku_checks_present,
+        "absent": dokku_checks_absent,
+    }
+
+    module = AnsibleModule(argument_spec=fields, supports_check_mode=False)
+    is_error, has_changed, result = choice_map.get(module.params["state"])(
+        module.params
+    )
+
+    if is_error:
+        module.fail_json(msg=result["error"], meta=result)
+    module.exit_json(changed=has_changed, meta=result)
+
+
+if __name__ == "__main__":
+    main()

molecule/default/verify.yml

@@ -245,3 +245,38 @@
       msg: |-
         'false' not found in output of 'dokku http-auth:report':
         {{ dokku_http_auth_off.stdout }}
+
+  # Testing dokku_checks
+  - name: Disabling the Zero Downtime deployment
+    dokku_checks:
+      app: example-app
+      state: absent
+
+  - name: Get checks output # noqa 301
+    command: dokku checks:report example-app
+    register: dokku_checks
+
+  - name: Check that the checks were disabled
+    assert:
+      that:
+      - "'_all_' in dokku_checks.stdout"
+      msg: |-
+        checks were not disabled in output of 'dokku checks':
+        {{ dokku_checks.stdout }}
+
+  - name: Re-enabling the Zero Downtime deployment
+    dokku_checks:
+      app: example-app
+      state: present
+
+  - name: Get checks output # noqa 301
+    command: dokku checks:report example-app
+    register: dokku_checks
+
+  - name: Check that the checks were re-enabled
+    assert:
+      that:
+      - "'none' in dokku_checks.stdout"
+      msg: |-
+        checks were not enabled in output of 'dokku checks':
+        {{ dokku_checks.stdout }}