Issue 2443 - Honour SKIP_DEPENDENCY_UPDATES environment variable

ensure_dependencies.py

 #!/usr/bin/env python
 # coding: utf-8
 
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import sys
 import os
 import posixpath
@@ skipping 208 matching lines @@
     return
 
   if type in revisions:
     revision = revisions[type]
   elif "*" in revisions:
     revision = revisions["*"]
   else:
     logging.warning("No revision specified for repository %s (type %s), skipping update" % (target, type))
     return
 
   resolved_revision = repo_types[type].get_revision_id(target, revision)

[Wladimir Palant, 2015/05/06 18:17:32]

For reference, I think the check belongs here:

if resolved_revision != current_revision and
os.environ.get("SKIP_ENSURE_DEPENDENCIES", "").lower() not in ("", "0",
"false"):
  logging.warning(...)
  sys.exit()

The repository will still be created if it doesn't exist yet - that's typically
a one-time thing when the build is created for the first time. I don't see any
use case where that would be an issue.

[kzar, 2015/05/07 13:02:38]

OK I've done this, I have some reservations though. The sys.exit here would
cause nested dependencies to be treated differently depending on the checked out
revision of the parent dependency, so instead I return.

Thing is I'm still not convinced about my latest patchset, it seems weird that
the script clones all the dependencies but then doesn't check out the
appropriate revision for them. I can't help but feel patch set 2 would have been
easier to reason with, but I'm happy to go with whatever the consensus is, I
don't expect to use this feature myself.

[Sebastian Noack, 2015/05/07 13:17:19]

Yeah, I'm pretty sure Wladimir meant to return here.
Patchset 2 certainly was a footgun. I really don't want to start over that
discussion. But I see your point about the kinda unexpected behavior with newly
cloned repos. It's not a very common case, but if you think it would be better
to either perform the update regardless of SKIP_DEPENDENCY_UPDATES  for freshly
cloned repos, or to skip cloning repos as well, fine with me.

[kzar, 2015/05/07 13:44:29]

Done.

   if not resolved_revision:
     logging.info("Revision %s is unknown, downloading remote changes" % revision)
     repo_types[type].pull(target)
     resolved_revision = repo_types[type].get_revision_id(target, revision)
     if not resolved_revision:
       raise Exception("Failed to resolve revision %s" % revision)
 
   current_revision = repo_types[type].get_revision_id(target)
   if resolved_revision != current_revision:
     logging.info("Updating repository %s to revision %s" % (target, resolved_revision))
@@ skipping 50 matching lines @@
     if not pattern in file_content:
       file_content.append(pattern)
       f.seek(0, os.SEEK_SET)
       f.truncate()
       for l in file_content:
         print >>f, l
 
 if __name__ == "__main__":
   logging.basicConfig(format='%(levelname)s: %(message)s', level=logging.INFO)
 
+  if os.environ.get("SKIP_ENSURE_DEPENDENCIES", "").lower() not in ("", "0", "false"):
+    logging.warning("SKIP_ENSURE_DEPENDENCIES environment variable set, skipping.")
+    sys.exit()
+
   parser = argparse.ArgumentParser(description="Verify dependencies for a set of repositories, by default the repository of this script.")
   parser.add_argument("repos", metavar="repository", type=str, nargs="*", help="Repository path")
   parser.add_argument("-q", "--quiet", action="store_true", help="Suppress informational output")
   args = parser.parse_args()
 
   if args.quiet:
     logging.disable(logging.INFO)
 
   repos = args.repos
   if not len(repos):
     repos = [os.path.dirname(__file__)]
   for repo in repos:
     resolve_deps(repo)