Allow extracting koji event from another compose

When multiple composes are chained, they should reuse the same event.
However it is tricky as the value would have to be passed by hand. This
patch makes it possible to read the value from another compose (the
first one in the chain).

JIRA: COMPOSE-2571
Signed-off-by: Lubomír Sedlář <lsedlar@redhat.com>

bin/pungi-koji

@@ -23,7 +23,7 @@ if here != '/usr/bin':
     sys.path[0] = os.path.dirname(here)
 
 from pungi.phases import PHASES_NAMES
-from pungi import get_full_version
+from pungi import get_full_version, util
 
 
 # force C locales
@@ -130,8 +130,9 @@ def main():
     parser.add_argument(
         "--koji-event",
         metavar="ID",
-        type=int,
-        help="specify a koji event for populating package set",
+        type=util.parse_koji_event,
+        help="specify a koji event for populating package set, either as event ID "
+             "or a path to a compose from which to reuse the event",
     )
     parser.add_argument(
         "--version",

pungi/util.py

@@ -13,8 +13,9 @@
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, see <https://gnu.org/licenses/>.
 
-
+import argparse
 import fnmatch
+import json
 import subprocess
 import os
 import shutil
@@ -836,3 +837,21 @@ def get_tz_offset():
     hours = offset / 3600
     minutes = (offset / 60) % 60
     return "%+03d:%02d" % (hours, minutes)
+
+
+def parse_koji_event(event):
+    """Process event specification. If event looks like a number, it will be
+    used as is. If a string is given, it will be interpreted as a path to the
+    topdir of another compose, from which an even it will be extracted.
+    """
+    try:
+        return int(event)
+    except ValueError:
+        pass
+    try:
+        with open(os.path.join(event, "work/global/koji-event")) as f:
+            return json.load(f)["id"]
+    except (IOError, OSError, KeyError):
+        raise argparse.ArgumentTypeError(
+            "%s is not a number or path to compose with valid Koji event" % event
+        )

tests/test_util.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python2
 # -*- coding: utf-8 -*-
 
+import argparse
 import mock
 import os
 import sys
@@ -685,5 +686,23 @@ class TestTZOffset(unittest.TestCase):
         self.assertEqual(util.get_tz_offset(), "+00:00")
 
 
+class TestParseKojiEvent(PungiTestCase):
+
+    def test_number(self):
+        self.assertEqual(util.parse_koji_event("1234"), 1234)
+
+    def test_correct_path(self):
+        touch(
+            os.path.join(self.topdir, 'work/global/koji-event'),
+            '{"id": 19769058, "ts": 1527641311.22855}'
+        )
+
+        self.assertEqual(util.parse_koji_event(self.topdir), 19769058)
+
+    def test_bad_path(self):
+        with self.assertRaises(argparse.ArgumentTypeError):
+            util.parse_koji_event(self.topdir)
+
+
 if __name__ == "__main__":
     unittest.main()