tests: Collect script output as binary, collect systemd journal, fix lxd.

This adds collection a gzip compressed systemd journal on systemd systems.
The file can later be reviewed with:
  zcat system.journal.gz > system.journal
  journalctl --file=system.journal [-o short-monotonic ..]

To support this:
  * modify test harness infrastructure to not assume content is utf-8.
  * fix lxd platform to support make '_execute' return bytes rather
    than a string. https://github.com/lxc/pylxd/issues/268

Also switched the base collectors to use /bin/sh as others already did.

1 files changed, 4 insertions, 2 deletions

diff --git a/tests/cloud_tests/testcases/base.py b/tests/cloud_tests/testcases/base.py
index 1c5b5405..20e95955 100644
--- a/tests/cloud_tests/testcases/base.py
+++ b/tests/cloud_tests/testcases/base.py
@@ -30,12 +30,14 @@ class CloudTestCase(unittest.TestCase):
             raise AssertionError('Key "{}" not in cloud config'.format(name))
         return self.cloud_config[name]
 
-    def get_data_file(self, name):
+    def get_data_file(self, name, decode=True):
         """Get data file failing test if it is not present."""
         if name not in self.data:
             raise AssertionError('File "{}" missing from collect data'
                                  .format(name))
-        return self.data[name]
+        if not decode:
+            return self.data[name]
+        return self.data[name].decode('utf-8')
 
     def get_instance_id(self):
         """Get recorded instance id."""