Adding workflow parameters validation

Change-Id: I55b4a03296ddbd1468c2a7dd1cc7b7e2d867351d

mistral/engine1/default_engine.py

@@ -51,6 +51,8 @@ class DefaultEngine(base.Engine):
 
             wf_spec = spec_parser.get_workflow_spec(wf_db.spec)
 
+            utils.validate_workflow_input(wf_db, wf_spec, workflow_input)
+
             exec_db = self._create_db_execution(
                 wf_db,
                 wf_spec,
@@ -69,7 +71,6 @@ class DefaultEngine(base.Engine):
 
     @u.log_exec(LOG)
     def on_task_result(self, task_id, raw_result):
-
         with db_api.transaction():
             task_db = db_api.get_task(task_id)
             exec_db = db_api.get_execution(task_db.execution_id)

mistral/engine1/utils.py

@@ -12,6 +12,8 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
+import copy
+
 from mistral.db.v2 import api as db_api
 from mistral import exceptions as exc
 from mistral import expressions as expr
@@ -22,6 +24,35 @@ from mistral.workflow import utils as wf_utils
 LOG = logging.getLogger(__name__)
 
 
+def validate_workflow_input(wf_db, wf_spec, wf_input):
+    input_param_names = copy.copy((wf_input or {}).keys())
+    missing_param_names = []
+
+    for p_name in wf_spec.get_parameters():
+        if p_name not in input_param_names:
+            missing_param_names.append(p_name)
+        else:
+            input_param_names.remove(p_name)
+
+    if missing_param_names or input_param_names:
+        msg = 'Invalid workflow input [workflow=%s'
+        msg_props = [wf_db.name]
+
+        if missing_param_names:
+            msg += ', missing=%s'
+            msg_props.append(missing_param_names)
+
+        if input_param_names:
+            msg += ', unexpected=%s'
+            msg_props.append(input_param_names)
+
+        msg += ']'
+
+        raise exc.WorkflowInputException(
+            msg % tuple(msg_props)
+        )
+
+
 def resolve_action(wf_name, wf_spec_name, action_spec_name):
     action_db = None
 

mistral/exceptions.py

@@ -85,6 +85,10 @@ class WorkflowException(MistralException):
     http_code = 400
 
 
+class WorkflowInputException(MistralException):
+    http_code = 400
+
+
 class ApplicationContextNotFoundException(MistralException):
     http_code = 400
     message = "Application context not found"

mistral/tests/unit/engine1/test_default_engine.py

@@ -19,6 +19,7 @@ from oslo.config import cfg
 from mistral.db.v2 import api as db_api
 from mistral.db.v2.sqlalchemy import models
 from mistral.engine1 import default_engine as d_eng
+from mistral import exceptions as exc
 from mistral.openstack.common import log as logging
 from mistral.services import workbooks as wb_service
 from mistral.tests import base
@@ -39,6 +40,10 @@ version: '2.0'
 workflows:
   wf1:
     type: reverse
+    parameters:
+      - param1
+      - param2
+
     tasks:
       task1:
         action: std.echo output="{$.param1}"
@@ -48,6 +53,7 @@ workflows:
       task2:
         action: std.echo output="{$.param2}"
         requires: [task1]
+
 """
 
 # TODO(rakhmerov): Add more advanced tests including various capabilities.
@@ -105,6 +111,24 @@ class DefaultEngineTest(base.DbTestCase):
         self.assertIn('__execution', task_db.in_context)
         self.assertDictEqual({'output': 'Hey'}, task_db.parameters)
 
+    def test_start_workflow_missing_parameters(self):
+        self.assertRaises(
+            exc.WorkflowInputException,
+            self.engine.start_workflow,
+            '%s.wf1' % self.wb_name,
+            None,
+            task_name='task2'
+        )
+
+    def test_start_workflow_unexpected_parameters(self):
+        self.assertRaises(
+            exc.WorkflowInputException,
+            self.engine.start_workflow,
+            '%s.wf1' % self.wb_name,
+            {'param1': 'Hey', 'param2': 'Hi', 'unexpected_param': 'val'},
+            task_name='task2'
+        )
+
     def test_on_task_result(self):
         wf_input = {
             'param1': 'Hey',