Generate default execution id

When execution id is not sent by the client, the api
will generate source execution id

Change-Id: Iae1ff327b5cb1af857d53ca53782d9fb30eefc27
Closes-Bug: #1774164

mistral/api/controllers/v2/execution.py

@@ -17,6 +17,7 @@
 #    limitations under the License.
 
 from oslo_log import log as logging
+from oslo_utils import uuidutils
 from pecan import rest
 from wsme import types as wtypes
 import wsmeext.pecan as wsme_pecan
@@ -36,7 +37,6 @@ from mistral.utils import merge_dicts
 from mistral.utils import rest_utils
 from mistral.workflow import states
 
-
 LOG = logging.getLogger(__name__)
 
 STATE_TYPES = wtypes.Enum(
@@ -228,19 +228,23 @@ class ExecutionsController(rest.RestController):
 
         exec_id = exec_dict.get('id')
 
-        source_execution_id = exec_dict.get('source_execution_id')
-
-        source_exec_dict = None
-
-        if exec_id:
+        if not exec_id:
+            exec_id = uuidutils.generate_uuid()
+            LOG.debug("Generated execution id [exec_id=%s]", exec_id)
+            exec_dict.update({'id': exec_id})
+            wf_ex = None
+        else:
             # If ID is present we need to check if such execution exists.
             # If yes, the method just returns the object. If not, the ID
             # will be used to create a new execution.
             wf_ex = _get_workflow_execution(exec_id, must_exist=False)
-
             if wf_ex:
                 return resources.Execution.from_db_model(wf_ex)
 
+        source_execution_id = exec_dict.get('source_execution_id')
+
+        source_exec_dict = None
+
         if source_execution_id:
             # If source execution is present we will perform a lookup for
             # previous workflow execution model and the information to start
@@ -267,7 +271,7 @@ class ExecutionsController(rest.RestController):
             result_exec_dict.get('workflow_id',
                                  result_exec_dict.get('workflow_name')),
             result_exec_dict.get('workflow_namespace', ''),
-            exec_id,
+            result_exec_dict.get('id'),
             result_exec_dict.get('input'),
             description=result_exec_dict.get('description', ''),
             **result_exec_dict.get('params', {})

mistral/tests/unit/api/v2/test_executions.py

@@ -496,19 +496,16 @@ class TestExecutionsController(base.APITest):
         self.assertIn(expected_fault, resp.json['faultstring'])
 
     @mock.patch.object(rpc_clients.EngineClient, 'start_workflow')
-    @mock.patch.object(db_api, 'load_workflow_execution')
-    def test_post_auto_id(self, load_wf_ex_func, start_wf_func):
+    def test_post_auto_id(self, start_wf_func):
         # NOTE: In fact, we use "white box" testing here to understand
         # if the REST controller calls other APIs as expected. This is
         # the only way of testing available with the current testing
         # infrastructure.
-        start_wf_func.return_value = WF_EX.to_dict()
+        wf_ex_dict = WF_EX.to_dict()
+        start_wf_func.return_value = wf_ex_dict
 
         json_body = WF_EX_JSON_WITH_DESC.copy()
 
-        # We don't want to pass execution ID in this case.
-        del json_body['id']
-
         expected_json = WF_EX_JSON_WITH_DESC
 
         resp = self.app.post_json('/v2/executions', json_body)
@@ -516,15 +513,13 @@ class TestExecutionsController(base.APITest):
         self.assertEqual(201, resp.status_int)
         self.assertDictEqual(expected_json, resp.json)
 
-        load_wf_ex_func.assert_not_called()
-
         kwargs = json.loads(expected_json['params'])
         kwargs['description'] = expected_json['description']
 
         start_wf_func.assert_called_once_with(
             expected_json['workflow_id'],
             '',
-            None,
+            wf_ex_dict['id'],
             json.loads(expected_json['input']),
             **kwargs
         )
@@ -630,10 +625,8 @@ class TestExecutionsController(base.APITest):
     @mock.patch.object(rpc_clients.EngineClient, 'start_workflow')
     def test_post_with_src_exec_id_without_exec_id(self, wf_exec_mock):
         source_wf_ex = copy.copy(SOURCE_WF_EX)
-        source_wf_ex.id = ""
 
         source_wf_ex_json = copy.copy(SOURCE_WF_EX_JSON_WITH_DESC)
-        source_wf_ex_json['id'] = ''
 
         wf_exec_mock.return_value = source_wf_ex.to_dict()
 
@@ -654,7 +647,7 @@ class TestExecutionsController(base.APITest):
         wf_exec_mock.assert_called_once_with(
             exec_dict['workflow_id'],
             '',
-            '',
+            exec_dict['id'],
             json.loads(exec_dict['input']),
             description=expected_description,
             **json.loads(exec_dict['params'])