Advanced publishing: add publishing of global variables

Partially implements: blueprint mistral-advanced-publishing-global-vars

Change-Id: I964e367063f7e9a846b86c1057116d202d62715a

mistral/tests/unit/engine/test_dataflow.py

@@ -713,7 +713,7 @@ class DataFlowEngineTest(engine_test_base.EngineTestCase):
 
         self.assertDictEqual(wf_input['a'], task1.published['published_a'])
 
-    def test_advanced_publishing_branch(self):
+    def test_branch_publishing_success(self):
         wf_text = """---
         version: 2.0
 
@@ -750,6 +750,88 @@ class DataFlowEngineTest(engine_test_base.EngineTestCase):
 
         self.assertDictEqual({"my_var": "my branch value"}, task1.published)
 
+    def test_global_publishing_success_access_via_root_context_(self):
+        wf_text = """---
+        version: '2.0'
+
+        wf:
+          tasks:
+            task1:
+              action: std.echo output="Hi"
+              on-success:
+                publish:
+                  global:
+                    my_var: <% task().result %>
+                next:
+                  - task2
+
+            task2:
+              action: std.echo output=<% $.my_var %>
+              publish:
+                result: <% task().result %>
+        """
+
+        wf_service.create_workflows(wf_text)
+
+        wf_ex = self.engine.start_workflow('wf', {})
+
+        self.await_workflow_success(wf_ex.id)
+
+        with db_api.transaction():
+            # Note: We need to reread execution to access related tasks.
+            wf_ex = db_api.get_workflow_execution(wf_ex.id)
+
+            tasks = wf_ex.task_executions
+
+        self._assert_single_item(tasks, name='task1')
+        task2 = self._assert_single_item(tasks, name='task2')
+
+        self.assertDictEqual({'result': 'Hi'}, task2.published)
+
+    def test_global_publishing_error_access_via_root_context(self):
+        wf_text = """---
+        version: '2.0'
+
+        wf:
+          tasks:
+            task1:
+              action: std.fail
+              on-success:
+                publish:
+                  global:
+                    my_var: "We got success"
+                next:
+                  - task2
+              on-error:
+                publish:
+                  global:
+                    my_var: "We got an error"
+                next:
+                  - task2
+
+            task2:
+              action: std.echo output=<% $.my_var %>
+              publish:
+                result: <% task().result %>
+        """
+
+        wf_service.create_workflows(wf_text)
+
+        wf_ex = self.engine.start_workflow('wf', {})
+
+        self.await_workflow_success(wf_ex.id)
+
+        with db_api.transaction():
+            # Note: We need to reread execution to access related tasks.
+            wf_ex = db_api.get_workflow_execution(wf_ex.id)
+
+            tasks = wf_ex.task_executions
+
+        self._assert_single_item(tasks, name='task1')
+        task2 = self._assert_single_item(tasks, name='task2')
+
+        self.assertDictEqual({'result': 'We got an error'}, task2.published)
+
 
 class DataFlowTest(test_base.BaseTest):
     def test_get_task_execution_result(self):

mistral/workflow/data_flow.py

@@ -203,12 +203,21 @@ def publish_variables(task_ex, task_spec):
     if not publish_spec:
         return
 
+    # Publish branch variables.
     branch_vars = publish_spec.get_branch()
 
     task_ex.published = expr.evaluate_recursively(branch_vars, expr_ctx)
 
+    # Publish global variables.
+    global_vars = publish_spec.get_global()
+
+    utils.merge_dicts(
+        task_ex.workflow_execution.context,
+        expr.evaluate_recursively(global_vars, expr_ctx)
+    )
+
     # TODO(rakhmerov):
-    # 1. Publish global and atomic variables.
+    # 1. Publish atomic variables.
     # 2. Add the field "publish" in TaskExecution model similar to "published"
     #    but containing info as
     #    {'branch': {vars}, 'global': {vars}, 'atomic': {vars}}