Serve releases.json from GitHub Pages to fix publishing race

Meson fetches releases.json directly from the repo, via a redirect from
wrapdb.mesonbuild.com.  When a PR lands, releases.json is updated
immediately but the GitHub release (with the wrap file, source mirror, and
patch zip) is updated after a delay, which can be lengthy if CI is heavily
loaded or down.  During this time, `meson wrap install` and
`meson wrap update` fail on the newly-updated wraps.

Maintain a second copy of releases.json that lags the one in Git, updating
it only after all the releases it describes have been published.  Publish
it via GitHub Pages: have create_release.py generate a static site, then
publish that in the release workflow.  Because of how GitHub Pages works
with custom domains, the new file will be available from
https://mesonbuild.com/wrapdb/releases.json.  Update the
wrapdb.mesonbuild.com nginx config to redirect there instead.

While we're here, minify the published releases.json.

Author: bgilbert

.github/workflows/release.yml

@@ -25,11 +25,29 @@ jobs:
       - name: Upload release assets
         run: |
           ./tools/create_release.py ${{ github.repository }} ${{ secrets.GITHUB_TOKEN }}
+      - name: Upload releases.json
+        uses: actions/upload-pages-artifact@v4
+
+  update_index:
+    needs: create_release
+    runs-on: ubuntu-latest
+    permissions:
+      pages: write
+      id-token: write
+    environment:
+      name: github-pages
+      url: ${{ steps.deploy.outputs.page_url }}releases.json
+    steps:
+      - name: Deploy releases.json
+        id: deploy
+        uses: actions/deploy-pages@v4
 
   # Ideally we should trigger Meson's CI to update the website, but unfortunately
   # it requires a Personal Access Token. Instead clone meson and do it ourself.
   # This job is copied from Meson's workflows.
   update_website:
+    # the site builder reads releases.json, so update that first
+    needs: update_index
     env:
       HAS_SSH_KEY: ${{ secrets.WEBSITE_PRIV_KEY != '' }}
     runs-on: ubuntu-latest

nginx/default

@@ -10,7 +10,7 @@
 
 server {
   location /v2 {
-    rewrite ^.*/v2/releases.json https://raw.githubusercontent.com/mesonbuild/wrapdb/master/releases.json permanent;
+    rewrite ^.*/v2/releases.json https://mesonbuild.com/wrapdb/releases.json permanent;
     rewrite ^.*/v2/([^/]+)/get_patch https://github.com/mesonbuild/wrapdb/releases/download/$1/$1_patch.zip permanent;
     rewrite ^.*/v2/([^/]+)/([^/]+).wrap https://github.com/mesonbuild/wrapdb/releases/download/$1/$2.wrap permanent;
   }

tools/create_release.py

@@ -193,6 +193,13 @@ def finalize(self) -> None:
         response.raise_for_status()
         print('Published release:', self.upload_url)
 
+def generate_site(releases: Releases) -> None:
+    site = Path('_site')  # default path for actions/upload-pages-artifact
+    if site.exists():
+        shutil.rmtree(site)
+    site.mkdir()
+    releases.save(dir=site, compact=True)
+
 def run(repo: T.Optional[str], token: T.Optional[str]) -> None:
     releases = Releases.load()
     stdout = subprocess.check_output(['git', 'tag'])
@@ -202,6 +209,7 @@ def run(repo: T.Optional[str], token: T.Optional[str]) -> None:
         latest_tag = f'{name}_{versions[0]}'
         if latest_tag not in tags:
             CreateRelease(repo, token, latest_tag)
+    generate_site(releases)
 
 if __name__ == '__main__':
     # Support local testing when passing no arguments

tools/utils.py

@@ -118,13 +118,18 @@ def load(cls) -> T.Self:
         with open(cls.FILENAME, encoding='utf-8') as f:
             return cls(json.load(f))
 
-    def encode(self) -> str:
-        return json.dumps(self, indent=2, sort_keys=True) + '\n'
-
-    def save(self) -> None:
-        with open(f'{self.FILENAME}.new', 'w', encoding='utf-8') as f:
-            f.write(self.encode())
-        os.rename(f'{self.FILENAME}.new', self.FILENAME)
+    def encode(self, *, compact: bool = False) -> str:
+        if compact:
+            kwargs: dict[str, T.Any] = dict(separators=(',', ':'))
+        else:
+            kwargs = dict(indent=2)
+        return json.dumps(self, sort_keys=True, **kwargs) + '\n'
+
+    def save(self, *, dir: Path = Path('.'), compact: bool = False) -> None:
+        temp = dir / f'{self.FILENAME}.new'
+        with temp.open('w', encoding='utf-8') as f:
+            f.write(self.encode(compact=compact))
+        temp.rename(dir / self.FILENAME)
 
     @classmethod
     def format(cls, *, check: bool = False) -> None: