Merge ~blake-rouse/maas:fix-snap-version-git into maas:master

[Blake Rouse]

Use new version-script in snapcraft YAML to calculate a nice version string for the MAAS snap.

[Blake Rouse (blake-rouse)]

Self-approving as this just fixes the version string.

review: Approve

diff --git a/.gitignore b/.gitignore
index f75bc00..789a2e1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,6 +2,7 @@
 *.egg
 *.egg-info
 *.log
+*.snap
 /.bzr
 /.coverage
 /.coverage.*
@@ -38,8 +39,11 @@
 /media/demo/*
 /media/development
 /parts
+/prime
 /services/*/supervise
+/snap/.snapcraft
 /src/maasserver/static/js/enums.js
+/stage
 /TAGS
 /tags
 /xunit.*.xml
diff --git a/snap/plugins/bzr_version.py b/snap/plugins/bzr_version.py
deleted file mode 100644
index 630bc84..0000000
--- a/snap/plugins/bzr_version.py
+++ /dev/null
@@ -1,34 +0,0 @@
-# Copyright 2017 Canonical Ltd.  This software is licensed under the
-# GNU Affero General Public License version 3 (see the file LICENSE).
-
-import os
-import subprocess
-
-import snapcraft
-
-
-class BZRVersionPlugin(snapcraft.BasePlugin):
-    """Plugin that patches snapcraft to append the version of the branch
-    to the version string in the snapcraft.yaml."""
-
-    def __init__(self, *args, **kwargs):
-        super(BZRVersionPlugin, self).__init__(*args, **kwargs)
-        # Patch snapcraft so the bzr revno is attached to the version
-        # of the snap. This really should be built inside of snapcraft.
-        create_packaging = snapcraft.internal.meta.create_snap_packaging
-
-        def wrap_create_packaging(config_data, project_options):
-            try:
-                revno = subprocess.check_output([
-                    'bzr', 'revno',
-                    os.path.abspath(os.path.dirname(self.project.parts_dir))])
-            except subprocess.CalledProcessError:
-                # This can fail when using 'cleanbuild'. This is because the
-                # bazaar branch can depend on a parent that is not copied into
-                # the container.
-                revno = b'UNKNOWN'
-            config_data['version'] += (
-                '+bzr%s-snap' % revno.decode('utf-8').strip())
-            return create_packaging(config_data, project_options)
-
-        snapcraft.internal.meta.create_snap_packaging = wrap_create_packaging
diff --git a/snap/snapcraft.yaml b/snap/snapcraft.yaml
index d059db1..8e72e25 100644
--- a/snap/snapcraft.yaml
+++ b/snap/snapcraft.yaml
@@ -1,5 +1,6 @@
 name: maas
-version: trunk
+version: git
+version-script: utilities/calc-snap-version  
 summary: Metal as a Service
 description: |
   Total automation of you physical servers for amazing data center
@@ -132,9 +133,3 @@ parts:
       - -conf
       - -plugins
       - -snapcraft.yaml
-  version:
-    plugin: bzr-version
-    stage:
-      - -*
-    prime:
-      - -*
diff --git a/src/maasserver/__init__.py b/src/maasserver/__init__.py
index fb0a0fb..cd6b4d6 100644
--- a/src/maasserver/__init__.py
+++ b/src/maasserver/__init__.py
@@ -14,7 +14,7 @@ import logging
 from os import environ
 
 
-__version__ = '2.2.0'
+__version__ = '2.3.0'
 
 default_app_config = 'maasserver.apps.MAASConfig'
 
diff --git a/utilities/calc-snap-version b/utilities/calc-snap-version
new file mode 100755
index 0000000..5c73d48
--- /dev/null
+++ b/utilities/calc-snap-version
@@ -0,0 +1,49 @@
+#!/usr/bin/env python3
+# Copyright 2017 Canonical Ltd.  This software is licensed under the
+# GNU Affero General Public License version 3 (see the file LICENSE).
+
+"""
+Calculates the version of the snap using git and the version defined in
+src/maasserver/__init__.py.
+"""
+
+import ast
+import os
+import sys
+import subprocess
+
+
+# Get the path to the src/maasserver/__init__.py.
+repo_path = os.path.dirname(
+    os.path.dirname(os.path.abspath(os.path.realpath(__file__))))
+init_path = os.path.join(repo_path, 'src', 'maasserver', '__init__.py')
+
+# Get the syntax tree for the file, since we don't want to actually import
+# that file into this script.
+with open(init_path, 'r') as stream:
+    init_ast = ast.parse(stream.read())
+
+# Get the version from the parsed ast tree.
+version = None
+for node in ast.walk(init_ast):
+    if isinstance(node, ast.Assign):
+        if node.targets:
+            if node.targets[0].id == '__version__':
+                version = node.value.s
+                break
+
+# Unable to get the version then just set it to 'master'.
+if not version:
+    version = 'master'
+
+# Describe number of commits in git.
+revno = subprocess.check_output(
+    ['git', '-C', repo_path, 'rev-list', '--count', 'HEAD'],
+    stderr=subprocess.DEVNULL).decode(sys.getfilesystemencoding()).strip()
+
+# Describe commit hash from git.
+commit = subprocess.check_output(
+    ['git', '-C', repo_path, 'describe', '--abbrev=7', '--always', '--dirty'],
+    stderr=subprocess.DEVNULL).decode(sys.getfilesystemencoding()).strip()
+
+print('%s-%s-%s-snap' % (version, revno, commit))