Adding some more constraints to cron trigger

* User was able to create some triggers
   with different names but the same first-time
   and count. Now it is fixed.

Closes-Bug: #1449514

Change-Id: Ifde94b2f183faad8c9a5bb8723f11945da5bc08a

mistral/db/sqlalchemy/migration/alembic_migrations/versions/003_cron_trigger_constraints.py

@@ -0,0 +1,46 @@
+# Copyright 2015 OpenStack Foundation.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""cron_trigger_constraints
+
+Revision ID: 003
+Revises: 002
+Create Date: 2015-05-25 13:09:50.190136
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '003'
+down_revision = '002'
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def upgrade():
+    op.add_column(
+        'cron_triggers_v2',
+        sa.Column('first_execution_time', sa.DateTime(), nullable=True)
+    )
+    op.drop_index('workflow_input_hash', table_name='cron_triggers_v2')
+    op.drop_index('workflow_input_hash_2', table_name='cron_triggers_v2')
+    op.create_unique_constraint(
+        None,
+        'cron_triggers_v2', [
+            'workflow_input_hash', 'workflow_name', 'pattern',
+            'project_id', 'workflow_params_hash', 'remaining_executions',
+            'first_execution_time'
+        ]
+    )

mistral/db/v2/sqlalchemy/api.py

@@ -793,6 +793,12 @@ def create_cron_trigger(values, session=None):
             "Duplicate entry for cron trigger %s: %s"
             % (cron_trigger.name, e.columns)
         )
+    # TODO(nmakhotkin): Remove this 'except' after fixing
+    # https://bugs.launchpad.net/oslo.db/+bug/1458583.
+    except db_exc.DBError as e:
+        raise exc.DBDuplicateEntry(
+            "Duplicate entry for cron trigger: %s" % e
+        )
 
     return cron_trigger
 

mistral/db/v2/sqlalchemy/models.py

@@ -248,13 +248,19 @@ class CronTrigger(mb.MistralSecureModelBase):
         sa.UniqueConstraint('name', 'project_id'),
         sa.UniqueConstraint(
             'workflow_input_hash', 'workflow_name', 'pattern', 'project_id',
-            'workflow_params_hash'
+            'workflow_params_hash', 'remaining_executions',
+            'first_execution_time'
         )
     )
 
     id = mb.id_column()
     name = sa.Column(sa.String(200))
-    pattern = sa.Column(sa.String(100))
+    pattern = sa.Column(
+        sa.String(100),
+        nullable=True,
+        default='0 0 30 2 0'  # Set default to 'never'.
+    )
+    first_execution_time = sa.Column(sa.DateTime, nullable=True)
     next_execution_time = sa.Column(sa.DateTime, nullable=False)
     workflow_name = sa.Column(sa.String(80))
     remaining_executions = sa.Column(sa.Integer)
@@ -281,6 +287,7 @@ class CronTrigger(mb.MistralSecureModelBase):
     def to_dict(self):
         d = super(CronTrigger, self).to_dict()
 
+        mb.datetime_to_str(d, 'first_execution_time')
         mb.datetime_to_str(d, 'next_execution_time')
 
         return d

mistral/services/triggers.py

@@ -87,6 +87,7 @@ def create_cron_trigger(name, workflow_name, workflow_input,
         values = {
             'name': name,
             'pattern': pattern,
+            'first_execution_time': first_time,
             'next_execution_time': next_time,
             'remaining_executions': count,
             'workflow_name': workflow_name,

mistral/tests/unit/services/test_trigger_service.py

@@ -70,6 +70,57 @@ class TriggerServiceV2Test(base.DbTestCase):
 
         self.assertEqual(datetime.datetime(2010, 8, 25, 0, 10), next_time)
 
+    def test_trigger_create_the_same_first_time_or_count(self):
+        t_s.create_cron_trigger(
+            'test',
+            self.wf.name,
+            {},
+            {},
+            '*/5 * * * *',
+            "4242-12-25 13:37",
+            2,
+            datetime.datetime(2010, 8, 25)
+        )
+
+        t_s.create_cron_trigger(
+            'test2',
+            self.wf.name,
+            {},
+            {},
+            '*/5 * * * *',
+            "4242-12-25 13:37",
+            4,
+            datetime.datetime(2010, 8, 25)
+        )
+
+        t_s.create_cron_trigger(
+            'test3',
+            self.wf.name,
+            {},
+            {},
+            '*/5 * * * *',
+            "5353-12-25 13:37",
+            2,
+            datetime.datetime(2010, 8, 25)
+        )
+
+        # Creations above should be ok.
+
+        # But creation with the same count and first time
+        # simultaneously leads to error.
+        self.assertRaises(
+            exc.DBDuplicateEntry,
+            t_s.create_cron_trigger,
+            'test4',
+            self.wf.name,
+            {},
+            {},
+            '*/5 * * * *',
+            "4242-12-25 13:37",
+            2,
+            None
+        )
+
     def test_trigger_create_wrong_workflow_input(self):
         wf_with_input = """---
         version: '2.0'