Merge ~nacc/git-ubuntu:lp1741949-unset-SNAP-calling-lxc into git-ubuntu:master

[Nish Aravamudan]

Make jenkins happy.

[Robie Basak (racb)]

If this is a workaround, please could we have a Launchpad bug on the underlying issue and then refer to that bug in a comment?

[Nish Aravamudan (nacc)]

I mean we have a bug (it's linked to this MP). I'm happy to add a comment inline.

8b21c8e... by Nish Aravamudan on 2018-01-09

add launchpad bug reference in comment

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:769c6756610bc480c65d5127948b52381119b67a
https://jenkins.ubuntu.com/server/job/git-ubuntu-ci/234/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Style Check
    SUCCESS: Unit Tests
    FAILED: Integration Tests

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/git-ubuntu-ci/234/rebuild

review: Needs Fixing (continuous-integration)

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:8b21c8e7bcaaa22fcfcbf73526d4b916cf51606e
https://jenkins.ubuntu.com/server/job/git-ubuntu-ci/235/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Style Check
    SUCCESS: Unit Tests
    FAILED: Integration Tests

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/git-ubuntu-ci/235/rebuild

review: Needs Fixing (continuous-integration)

[Nish Aravamudan (nacc)]

Superseding with https://code.launchpad.net/~nacc/usd-importer/+git/usd-importer/+merge/335909

Unmerged commits

8b21c8e... by Nish Aravamudan on 2018-01-09

add launchpad bug reference in comment

769c675... by Nish Aravamudan on 2018-01-09

build: unset SNAP in lxc's env

Ever since lxc gained snap support, it assumed that if SNAP is set in
it's environment that lxc itself was running as a SNAP. This is not
necessarily the case when git-ubuntu itself is a classic snap (and thus
has SNAP set in its environment) but is calling lxc in the host. Unset
SNAP manually on lxc run() calls.

LP: #1741949

diff --git a/gitubuntu/build.py b/gitubuntu/build.py
index 072d3e7..a476702 100644
--- a/gitubuntu/build.py
+++ b/gitubuntu/build.py
@@ -946,6 +946,16 @@ def _run_in_lxd(container_name, args, user=None, **kwargs):
                 raise
         cmd.extend(['sudo', '-s', '-H', '-u', user,])
     cmd.extend(args)
+    # lxd assumes that if SNAP is set in the environment, that it is
+    # running as a snap. That is not necessarily true when git-ubuntu is
+    # the snapped application. So unset SNAP before we exec.
+    # LP: #1741949
+    try:
+        env = kwargs['env']
+    except KeyError:
+        env = dict()
+    env.update({'SNAP': ""})
+    kwargs['env'] = env
     return run(cmd, **kwargs)
 
 def do_build_lxd_exitstack(