From 652e8b3478a75e67c97db2bc32fea13dbe5eb3ef Mon Sep 17 00:00:00 2001
From: Guillaume Boutry <guillaume.boutry@canonical.com>
Date: Mon, 29 Jan 2024 08:41:51 +0100
Subject: [PATCH] Add module to read metadata from downloaded artifact

Since charmcraft 2.5, all properties are to be written in
charmcraft.yaml. But when the charm is generated, the artifact will
still contain the metadata.yaml. Adding a module to read the artifact's
metadata.

Two benefits from this:
- don't have to check whether it's a charm with charmcraft.yaml or
  metadata.yaml
- upload oci images written in the artifact's resources section

Change-Id: I971973859d0ef76840b5c1d60098a31e55a8d28b
---
 ansible.cfg                            |  2 ++
 ansible_library/charm_metadata.py      | 48 ++++++++++++++++++++++++++
 roles/charm-publish/tasks/publish.yaml | 21 +++--------
 3 files changed, 54 insertions(+), 17 deletions(-)
 create mode 100644 ansible.cfg
 create mode 100644 ansible_library/charm_metadata.py

diff --git a/ansible.cfg b/ansible.cfg
new file mode 100644
index 00000000..135f10a1
--- /dev/null
+++ b/ansible.cfg
@@ -0,0 +1,2 @@
+[defaults]
+library = ./ansible_library
diff --git a/ansible_library/charm_metadata.py b/ansible_library/charm_metadata.py
new file mode 100644
index 00000000..f4c8e356
--- /dev/null
+++ b/ansible_library/charm_metadata.py
@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+# Copyright 2024 Canonical Ltd.
+
+import pathlib
+import zipfile
+
+import yaml
+from ansible.module_utils.basic import AnsibleModule
+
+DOCUMENTATION = r"""
+module: charm_metadata
+author: Canonical
+description: Read charm metadata from a charm artifact
+
+options:
+  path:
+    description: path to charm artifact
+    required: yes
+"""
+
+EXAMPLES = r"""
+- name: Read charm metadata
+  charm_metadata:
+    charm: /tmp/keystone.charm
+"""
+
+
+def run_module():
+    module = AnsibleModule(
+        argument_spec=dict(
+            path=dict(type="str", required=True),
+        )
+    )
+
+    path: str = module.params["path"]  # type: ignore
+    charm_path = pathlib.Path(path)
+    if not charm_path.exists():
+        module.fail_json(msg=f"charm {path} not found on disk")
+
+    with zipfile.ZipFile(charm_path, "r") as charm_zip:
+        metadata = charm_zip.read("metadata.yaml")
+    metadata_dict = yaml.safe_load(metadata)
+
+    module.exit_json(changed=False, metadata=metadata_dict)
+
+
+if __name__ == "__main__":
+    run_module()
diff --git a/roles/charm-publish/tasks/publish.yaml b/roles/charm-publish/tasks/publish.yaml
index 1206cedf..8c6642cf 100644
--- a/roles/charm-publish/tasks/publish.yaml
+++ b/roles/charm-publish/tasks/publish.yaml
@@ -20,27 +20,14 @@
         name: ensure-docker
 
     - name: Get metadata.yaml information
-      stat:
-        path: "{{ zuul.executor.work_root+'/'+zuul.project.src_dir+'/charms/'+charm_build_name+'/metadata.yaml' }}"
-      register: metadata_file
-
-    - name: Get charmcraft.yaml information
-      stat:
-        path: "{{ zuul.executor.work_root+'/'+zuul.project.src_dir+'/charms/'+charm_build_name+'/charmcraft.yaml' }}"
-      register: charmcraft_file
-
-    - name: Register resource file
-      set_fact:
-        resource_file: "{{ metadata_file.stat.exists | ternary(metadata_file.stat.path, charmcraft_file.stat.path) }}"
-
-    - name: Which metadata file is used
-      debug:
-        msg: "{{ resource_file }}"
+      charm_metadata:
+        path: "{{ zuul.project.src_dir }}/{{ charm_build_name }}.charm"
+      register: charm_metadata
 
     - name: Upload oci-image to charmhub
       register: upload_oci_image_output
       vars:
-        metadata: "{{ lookup('file', resource_file) | from_yaml }}"
+        metadata: "{{ charm_metadata['metadata'] }}"
       args:
         executable: /bin/bash
       shell: |