ostree: Add notification handler to wait for signature

This script can be used as a notification handler. For most messages it
does nothing, but when it sees a new commit in an ostree repo, it will
wait for a signature of the new commit to appear.

This is useful for building images later so that they include the
signature as well.

Fixes: https://pagure.io/pungi/issue/650
Signed-off-by: Lubomír Sedlář <lsedlar@redhat.com>

bin/pungi-wait-for-signed-ostree-handler

@@ -0,0 +1,37 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+from __future__ import print_function
+
+import argparse
+import datetime
+import json
+import os
+import sys
+import time
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser()
+    parser.add_argument('cmd')
+    opts = parser.parse_args()
+
+    if opts.cmd != 'ostree':
+        # Not an announcement of new ostree commit, nothing to do.
+        sys.exit()
+
+    try:
+        data = json.load(sys.stdin)
+    except ValueError:
+        print('Failed to decode data', file=sys.stderr)
+        sys.exit(1)
+
+    repo = data['local_repo_path']
+    commit = data['commitid']
+    path = '%s/objects/%s/%s.commitmeta' % (repo, commit[:2], commit[2:])
+
+    while not os.path.exists(path):
+        print('%s: Commit not signed yet, waiting...'
+              % datetime.datetime.utcnow())
+        time.sleep(5)
+
+    print('Found signature.')

setup.py

@@ -43,6 +43,7 @@ setup(
         'bin/pungi-koji',
         'bin/pungi-make-ostree',
         'bin/pungi-patch-iso',
+        'bin/pungi-wait-for-signed-ostree-handler',
 
         'contrib/yum-dnf-compare/pungi-compare-depsolving',
     ],