Add script to download packages from GitHub

.gitignore

@@ -14,3 +14,4 @@ env?
 .vscode/
 /rel
 /wheels
+/packages

scripts/build/download_packages.py

@@ -0,0 +1,77 @@
+#!/usr/bin/env python
+"""Download packages from github actions artifacts
+"""
+
+import io
+import os
+import sys
+import logging
+from pathlib import Path
+from zipfile import ZipFile
+
+import requests
+
+logger = logging.getLogger()
+logging.basicConfig(
+    level=logging.INFO, format="%(asctime)s %(levelname)s %(message)s"
+)
+
+REPOS = "psycopg/psycopg2"
+WORKFLOW_NAME = "Build packages"
+
+
+class ScriptError(Exception):
+    """Controlled exception raised by the script."""
+
+
+def main():
+    try:
+        token = os.environ["GITHUB_TOKEN"]
+    except KeyError:
+        raise ScriptError("please set a GITHUB_TOKEN to download artifacts")
+
+    s = requests.Session()
+    s.headers["Accept"] = "application/vnd.github.v3+json"
+    s.headers["Authorization"] = f"token {token}"
+
+    logger.info("looking for recent runs")
+    resp = s.get(f"https://api.github.com/repos/{REPOS}/actions/runs?per_page=10")
+    resp.raise_for_status()
+    for run in resp.json()["workflow_runs"]:
+        if run["name"] == WORKFLOW_NAME:
+            break
+    else:
+        raise ScriptError(f"couldn't find {WORKFLOW_NAME!r} in recent runs")
+
+    logger.info(f"looking for run {run['id']} artifacts")
+    resp = s.get(f"{run['url']}/artifacts")
+    resp.raise_for_status()
+    artifacts = resp.json()["artifacts"]
+
+    dest = Path("packages")
+    if not dest.exists():
+        logger.info(f"creating dir {dest}")
+        dest.mkdir()
+
+    for artifact in artifacts:
+        logger.info(f"downloading {artifact['name']} archive")
+        zip_url = artifact["archive_download_url"]
+        resp = s.get(zip_url)
+        with ZipFile(io.BytesIO(resp.content)) as zf:
+            logger.info("extracting archive content")
+            zf.extractall(dest)
+
+    logger.info(f"now you can run: 'twine upload -s {dest}/*'")
+
+
+if __name__ == "__main__":
+    try:
+        sys.exit(main())
+
+    except ScriptError as e:
+        logger.error("%s", e)
+        sys.exit(1)
+
+    except KeyboardInterrupt:
+        logger.info("user interrupt")
+        sys.exit(1)