Merge ~jocave/checkbox-support:snap-utils-system into checkbox-support:master

[Jonathan Cave]

Add some functions that use snapd API to get information about the running system. Mostly assertion parsing code I think shouldn't be copied around our test code base.

Tested using the new resource job that will follow in a p-p-resource MR.

[Sylvain Pineau (sylvain-pineau)]

+1

review: Approve

diff --git a/checkbox_support/snap_utils/system.py b/checkbox_support/snap_utils/system.py
 new file mode 100644
index 0000000..8e3e80c
--- /dev/null
+++ b/checkbox_support/snap_utils/system.py
@@ -0,0 +1,54 @@
+# Copyright 2019 Canonical Ltd.
+# All rights reserved.
+#
+# Written by:
+#    Jonathan Cave <[e-mail]>
+
+import io
+import yaml
+
+from checkbox_support.snap_utils.snapd import Snapd
+
+
+def get_kernel_snap():
+    snap = None
+    assertion_stream = Snapd().get_assertions('model')
+    count = int(assertion_stream.headers['X-Ubuntu-Assertions-Count'])
+    if count > 0:
+        for line in io.StringIO(assertion_stream.text):
+            if line.count(':') == 1:
+                key, val = [x.strip() for x in line.split(':')]
+                if key == 'kernel':
+                    if '=' in val:
+                        snap, _ = [x.strip() for x in val.split('=')]
+                    else:
+                        snap = val
+                    break
+    return snap
+
+
+def get_gadget_snap():
+    snap = None
+    assertion_stream = Snapd().get_assertions('model')
+    count = int(assertion_stream.headers['X-Ubuntu-Assertions-Count'])
+    if count > 0:
+        for line in io.StringIO(assertion_stream.text):
+            if line.count(':') == 1:
+                key, val = [x.strip() for x in line.split(':')]
+                if key == 'gadget':
+                    if '=' in val:
+                        snap, _ = [x.strip() for x in val.split('=')]
+                    else:
+                        snap = val
+                    break
+    return snap
+
+
+def get_bootloader():
+    bootloader = None
+    gadget_yaml = '/snap/{}/current/meta/gadget.yaml'.format(get_gadget_snap())
+    with open(gadget_yaml) as f:
+        data = yaml.load(f)
+        for k in data['volumes'].keys():
+            bootloader = data['volumes'][k]['bootloader']
+    return bootloader