add postgres service helper

plugins/modules/postgres.py

@@ -0,0 +1,95 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# Copyright: (c) 2024, Luca Bilke <luca@bil.ke>
+# MIT License (see LICENSE)
+
+# TODO: write ansible sections
+
+DOCUMENTATION = r"""
+"""
+
+EXAMPLES = r"""
+"""
+
+RETURN = r"""
+"""
+
+from __future__ import annotations  # pyright: ignore[reportGeneralTypeIssues]
+
+import shlex
+
+from ansible_collections.snailed.ez_compose.plugins.module_utils.common import (
+    State,
+    run_service,
+    update_service,
+)
+
+
+def helper(state: State) -> State:
+    backup = state.module.params.get("backup", True)
+    database = state.module.params["database"]
+    username = state.module.params["username"]
+    password = state.module.params["password"]
+    name = state.module.params["name"]
+    project_name = state.module.params["project_name"]
+
+    volumes = [
+        {
+            "source": name,
+            "target": "/var/lib/postgresql/data",
+            "type": "volume",
+        }
+    ]
+
+    environment = {
+        "POSTGRES_DB": database,
+        "POSTGRES_USER": username,
+        "POSTGRES_PASSWORD": password,
+    }
+
+    labels: dict[str, str] = {}
+
+    if backup:
+        labels.update(
+            {
+                "docker-volume-backup.archive-pre": (
+                    "/bin/sh -c '"
+                    f"PGPASSWORD={shlex.quote(password)} "
+                    "pg_dumpall "
+                    f"-U {shlex.quote(username)} "
+                    f"-f /backup/{shlex.quote(project_name)}.sql"
+                    "'"
+                )
+            }
+        )
+
+        volumes.append(
+            {
+                "type": "volume",
+                "source": f"{name}_backup",
+                "target": "/backup",
+            }
+        )
+
+    update = {
+        "environment": environment,
+        "volumes": volumes,
+        "labels": labels,
+    }
+
+    return update_service(state, update)
+
+
+def main():
+    extra_args = {
+        "archive": {"type": "bool"},
+        "database": {"type": "str", "required": True},
+        "username": {"type": "str", "required": True},
+        "password": {"type": "str", "required": True},
+    }
+    run_service(extra_args, helper)
+
+
+if __name__ == "__main__":
+    main()