[v2,3/5] toaster: Store recipe variable snapshots

diff --git a/lib/bb/ui/buildinfohelper.py b/lib/bb/ui/buildinfohelper.py
index 4ee45d67a..679f016bd 100644
--- a/lib/bb/ui/buildinfohelper.py
+++ b/lib/bb/ui/buildinfohelper.py
@@ -8,8 +8,10 @@ 
 
 import sys
 import bb
+import json
 import re
 import os
+import zlib
 
 import django
 from django.utils import timezone
@@ -31,7 +33,7 @@  from orm.models import Target_Image_File, TargetKernelFile, TargetSDKFile
 from orm.models import Variable, VariableHistory
 from orm.models import Package, Package_File, Target_Installed_Package, Target_File
 from orm.models import Task_Dependency, Package_Dependency
-from orm.models import Recipe_Dependency, Provides
+from orm.models import Recipe_Dependency, RecipeVariable, Provides
 from orm.models import Project, CustomImagePackage
 from orm.models import signal_runbuilds
 
@@ -1459,6 +1461,23 @@  class BuildInfoHelper(object):
                         t.save()
             self.internal_state['recipes'][pn] = recipe
 
+        if any('recipe_variables' in recipe_data
+               for recipe_data in event._depgraph['pn'].values()):
+            recipe_variables = []
+            for pn, recipe_data in event._depgraph['pn'].items():
+                variables = recipe_data.get('recipe_variables')
+                if variables is None:
+                    continue
+                recipe_variables.append(RecipeVariable(
+                    build=self.internal_state['build'],
+                    recipe=self.internal_state['recipes'][pn],
+                    variables=variables,
+                    variable_count=len(json.loads(zlib.decompress(variables)))))
+            with transaction.atomic():
+                RecipeVariable.objects.filter(
+                    build=self.internal_state['build']).delete()
+                RecipeVariable.objects.bulk_create(recipe_variables)
+
         # we'll not get recipes for key w/ values listed in ASSUME_PROVIDED
 
         assume_provided = self.server.runCommand(["getVariable", "ASSUME_PROVIDED"])[0].split()
diff --git a/lib/toaster/tests/db/test_db.py b/lib/toaster/tests/db/test_db.py
index 072ab9436..7c48b1de3 100644
--- a/lib/toaster/tests/db/test_db.py
+++ b/lib/toaster/tests/db/test_db.py
@@ -24,6 +24,10 @@ 
 
 import sys
 import pytest
+from types import SimpleNamespace
+from unittest.mock import Mock, patch
+import json
+import zlib
 
 try:
     from StringIO import StringIO
@@ -34,6 +38,11 @@  from contextlib import contextmanager
 
 from django.core import management
 from django.test import TestCase
+from django.utils import timezone
+
+from bb.ui.buildinfohelper import BuildInfoHelper, ORMWrapper
+from orm.models import Build, Layer, Layer_Version, Project, Recipe
+from orm.models import RecipeVariable
 
 
 @contextmanager
@@ -56,3 +65,95 @@  class MigrationTest(TestCase):
 
         with capture(makemigrations) as output:
             self.assertEqual(output, "No changes detected\n")
+
+
+class RecipeVariableTest(TestCase):
+
+    def setUp(self):
+        now = timezone.now()
+        project = Project.objects.get_or_create_default_project()
+        self.build = Build.objects.create(
+            project=project, machine='', distro='', distro_version='',
+            started_on=now, completed_on=now, cooker_log_path='',
+            bitbake_version='', progress_item='')
+        layer = Layer.objects.create(name='test', layer_index_url='')
+        self.layer_version = Layer_Version.objects.create(
+            build=self.build, layer=layer, branch='', commit='',
+            local_path='/layer')
+
+    def _store(self, recipe_data):
+        if 'recipe_variables' in recipe_data:
+            recipe_data = dict(recipe_data)
+            recipe_data['recipe_variables'] = zlib.compress(json.dumps(
+                recipe_data['recipe_variables'], separators=(',', ':')
+            ).encode('utf-8'))
+        helper = BuildInfoHelper.__new__(BuildInfoHelper)
+        helper.internal_state = {'build': self.build, 'targets': []}
+        helper.orm_wrapper = ORMWrapper()
+        helper.server = Mock()
+        helper.server.runCommand.return_value = ['', None]
+        helper._get_layer_version_for_path = Mock(return_value=self.layer_version)
+        event = SimpleNamespace(_depgraph={
+            'layer-priorities': [],
+            'pn': {'test': dict({'filename': '/layer/test.bb'}, **recipe_data)},
+            'depends': {'test': []},
+            'tdepends': {},
+        })
+
+        helper.store_dependency_information(event)
+
+        return helper.internal_state['recipes']['test']
+
+    def test_dependency_information_stores_recipe_variables(self):
+        recipe = self._store({'recipe_variables': {'EMPTY': '', 'FOO': 'bar'}})
+
+        snapshot = RecipeVariable.objects.get(build=self.build, recipe=recipe)
+        self.assertEqual(
+            json.loads(zlib.decompress(snapshot.variables)),
+            {'EMPTY': '', 'FOO': 'bar'})
+        self.assertEqual(snapshot.variable_count, 2)
+
+    def test_old_payload_does_not_delete_recipe_variables(self):
+        recipe = self._store({'recipe_variables': {'FOO': 'bar'}})
+        self._store({})
+
+        snapshot = RecipeVariable.objects.get(build=self.build, recipe=recipe)
+        self.assertEqual(
+            json.loads(zlib.decompress(snapshot.variables)), {'FOO': 'bar'})
+
+    def test_dependency_information_replaces_recipe_variables(self):
+        recipe = self._store({'recipe_variables': {'FOO': 'old'}})
+        self._store({'recipe_variables': {'BAR': 'new'}})
+
+        snapshot = RecipeVariable.objects.get(build=self.build, recipe=recipe)
+        self.assertEqual(
+            json.loads(zlib.decompress(snapshot.variables)), {'BAR': 'new'})
+        self.assertEqual(snapshot.variable_count, 1)
+
+    def test_dependency_information_removes_stale_recipe_snapshot(self):
+        stale_recipe = Recipe.objects.create(
+            name='stale', version='', layer_version=self.layer_version,
+            file_path='stale.bb')
+        RecipeVariable.objects.create(
+            build=self.build, recipe=stale_recipe,
+            variables=zlib.compress(b'{"STALE":"value"}'))
+
+        current_recipe = self._store({'recipe_variables': {'FOO': 'bar'}})
+
+        self.assertFalse(RecipeVariable.objects.filter(
+            build=self.build, recipe=stale_recipe).exists())
+        self.assertTrue(RecipeVariable.objects.filter(
+            build=self.build, recipe=current_recipe).exists())
+
+    def test_dependency_information_rolls_back_failed_bulk_create(self):
+        recipe = self._store({'recipe_variables': {'FOO': 'old'}})
+        with patch.object(RecipeVariable.objects, 'bulk_create',
+                          side_effect=RuntimeError('injected failure')):
+            with self.assertRaisesRegex(RuntimeError, 'injected failure'):
+                self._store({'recipe_variables': {'FOO': 'new'}})
+
+        snapshots = RecipeVariable.objects.filter(build=self.build)
+        self.assertEqual(snapshots.count(), 1)
+        snapshot = snapshots.get(recipe=recipe)
+        self.assertEqual(
+            json.loads(zlib.decompress(snapshot.variables)), {'FOO': 'old'})