From f830aaa90c5ca008cde90d95d95719e809abde21 Mon Sep 17 00:00:00 2001
From: Liam Young <liam.young@canonical.com>
Date: Mon, 30 Jul 2018 07:32:18 +0000
Subject: [PATCH] Allow charms to override local overlay

The local overlay ('local-charm-overlay.yaml') is generated on the
fly during deploy time and it assumes that the application name
will match the charm name. However this is not always the case so
allow charms to override the deploy time generated template with
one from the local tests/bundle/overlay directory.

This is really another stop-gap until the whole bundle generation
piece is rewritten.
---
 .../test_zaza_charm_lifecycle_deploy.py       | 27 +++++++++++++++++++
 zaza/charm_lifecycle/deploy.py                |  9 ++++---
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/unit_tests/test_zaza_charm_lifecycle_deploy.py b/unit_tests/test_zaza_charm_lifecycle_deploy.py
index 235f6be..a547cad 100644
--- a/unit_tests/test_zaza_charm_lifecycle_deploy.py
+++ b/unit_tests/test_zaza_charm_lifecycle_deploy.py
@@ -118,6 +118,33 @@ class TestCharmLifecycleDeploy(ut_utils.BaseTestCase):
         self.get_template.return_value = None
         self.assertIsNone(lc_deploy.render_overlay('mybundle.yaml', '/tmp/'))
 
+    def test_render_local_overlay(self):
+        self.patch_object(lc_deploy.jinja2, 'Environment')
+        self.patch_object(lc_deploy, 'get_template', return_value='atemplate')
+        self.patch_object(lc_deploy, 'render_template')
+        self.assertEqual(
+            lc_deploy.render_local_overlay('/target'),
+            '/target/local-charm-overlay.yaml')
+        self.assertFalse(self.Environment.called)
+        self.render_template.assert_called_once_with(
+            'atemplate',
+            '/target/local-charm-overlay.yaml')
+
+    def test_render_local_overlay_default(self):
+        jenv_mock = mock.MagicMock()
+        jenv_mock.from_string.return_value = 'atemplate'
+        self.patch_object(lc_deploy.jinja2, 'Environment',
+                          return_value=jenv_mock)
+        self.patch_object(lc_deploy, 'get_template', return_value=None)
+        self.patch_object(lc_deploy, 'render_template')
+        self.assertEqual(
+            lc_deploy.render_local_overlay('/target'),
+            '/target/local-charm-overlay.yaml')
+        jenv_mock.from_string.assert_called_once_with(mock.ANY)
+        self.render_template.assert_called_once_with(
+            'atemplate',
+            '/target/local-charm-overlay.yaml')
+
     def test_render_overlays(self):
         RESP = {
             'mybundles/mybundle.yaml': '/tmp/mybundle.yaml'}
diff --git a/zaza/charm_lifecycle/deploy.py b/zaza/charm_lifecycle/deploy.py
index 7a72f7c..96ae68d 100755
--- a/zaza/charm_lifecycle/deploy.py
+++ b/zaza/charm_lifecycle/deploy.py
@@ -24,6 +24,7 @@ applications:
   {{ charm_name }}:
     charm: {{ charm_location }}
 """
+LOCAL_OVERLAY_TEMPLATE_NAME = 'local-charm-overlay.yaml'
 
 
 def is_valid_env_key(key):
@@ -169,11 +170,13 @@ def render_local_overlay(target_dir):
     :returns: Path to rendered overlay
     :rtype: str
     """
-    template = jinja2.Environment(loader=jinja2.BaseLoader).from_string(
-        LOCAL_OVERLAY_TEMPLATE)
+    template = get_template(LOCAL_OVERLAY_TEMPLATE_NAME)
+    if not template:
+        template = jinja2.Environment(loader=jinja2.BaseLoader).from_string(
+            LOCAL_OVERLAY_TEMPLATE)
     rendered_template_file = os.path.join(
         target_dir,
-        os.path.basename('local-charm-overlay.yaml'))
+        os.path.basename(LOCAL_OVERLAY_TEMPLATE_NAME))
     render_template(template, rendered_template_file)
     return rendered_template_file