Merge pull request #106 from projectsyn/feat/post-gen-project-hook-pa…

…ckage-rules

Generate component `renovate.json` in post-gen-project hook

README.md

@@ -12,3 +12,11 @@ See https://syn.tools/syn/how-tos/prepare_for_component_sync.html
 * Push or merge to `main`
 * Via workflow dispatch (https://github.com/projectsyn/commodore-component-template/actions/workflows/sync.yaml)
 You can provide a regex to only sync selected components via workflow dispatch.
+
+## Notes regarding the template
+
+The base template is stored in `{{ cookiecutter.slug }}`.
+However, a part of the template is managed by a custom Python hook in `hooks/post_gen_project.py`
+
+Notably, the Python hook will generate a suitable `renovate.json` for the rendered template.
+We've switched to this approach since the logic that defines the contents of the `renovate.json` has become complex enough that templating JSON with Jinja2 isn't readable anymore.

hooks/post_gen_project.py

@@ -1,3 +1,4 @@
+import json
 import os
 import shutil
 
@@ -7,6 +8,9 @@
 
 create_lib = "{{ cookiecutter.add_lib }}" == "y"
 add_golden = "{{ cookiecutter.add_golden }}" == "y"
+add_matrix = "{{ cookiecutter.add_matrix }}" == "y"
+automerge_patch = "{{ cookiecutter.automerge_patch }}" == "y"
+automerge_patch_v0 = "{{ cookiecutter.automerge_patch_v0 }}" == "y"
 
 if not create_lib:
     shutil.rmtree("lib")
@@ -35,5 +39,62 @@
 if not add_golden:
     shutil.rmtree("tests/golden")
 
+renovatejson = {
+    "extends": [
+        "config:base",
+        ":gitSignOff",
+        ":disableDependencyDashboard",
+    ],
+    "ignorePaths": [".github/**"],
+    "labels": ["dependency"],
+    "separateMinorPatch": True,
+}
+
+if add_golden:
+    if add_matrix:
+        cmd = "make gen-golden-all"
+    else:
+        cmd = "make gen-golden"
+
+    # Add postUpgradeTask to run make gen-golden(-all) if golden tests are enabled.
+    renovatejson["postUpgradeTasks"] = {
+        "commands": [cmd],
+        "fileFilters": ["tests/golden/**"],
+        "executionMode": "update",
+    }
+    # suppress artifact error notifications if postUpgradeTask is configured, since upstream hosted
+    # renovate will complain when any postUpgradeTasks are present.
+    renovatejson["suppressNotifications"] = ["artifactErrors"]
+
+# We always add an empty package rules list
+renovatejson["packageRules"] = []
+
+if automerge_patch:
+    # automerge patch PRs
+    patch_rule = {
+        "matchUpdateTypes": ["patch"],
+        # negative match: do not match versions that match regex `^v?0\.`
+        "matchCurrentVersion": "!/^v?0\\./",
+        "automerge": True,
+        # NOTE: We can't use Platform Automerge because the repositories are configured manually,
+        # so we can't be sure the "require status checks" option is always enabled, and without
+        # that, platformAutomerge does not wait for tests to pass.
+        "platformAutomerge": False,
+        # NOTE: We need to add all the labels we want here, renovate doesn't inherit globally
+        # specified labels for package rules
+        "labels": ["dependency", "automerge"],
+    }
+    if automerge_patch_v0:
+        # remove match current version if we want v0.x patch automerge
+        del patch_rule["matchCurrentVersion"]
+
+    renovatejson["packageRules"].append(patch_rule)
+
+# NOTE: Later rules in `packageRules` take precedence
+
+with open("renovate.json", "w", encoding="utf-8") as f:
+    json.dump(renovatejson, f, indent=2)
+    f.write("\n")
+
 if Path(".sync.yml").is_file():
     os.unlink(Path(".sync.yml"))