api: Add endpoint for simulation jobs

This change adds an API endpoint for simulation jobs which allows API
consumers to manage simulation jobs without needing direct database
access that is currently needed for the web runner.

3 files changed, 134 insertions, 31 deletions

diff --git a/opendc-web/opendc-web-api/opendc/api/jobs.py b/opendc-web/opendc-web-api/opendc/api/jobs.py
new file mode 100644
index 00000000..5feaea16
--- /dev/null
+++ b/opendc-web/opendc-web-api/opendc/api/jobs.py
@@ -0,0 +1,105 @@
+#  Copyright (c) 2021 AtLarge Research
+#
+#  Permission is hereby granted, free of charge, to any person obtaining a copy
+#  of this software and associated documentation files (the "Software"), to deal
+#  in the Software without restriction, including without limitation the rights
+#  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+#  copies of the Software, and to permit persons to whom the Software is
+#  furnished to do so, subject to the following conditions:
+#
+#  The above copyright notice and this permission notice shall be included in all
+#  copies or substantial portions of the Software.
+#
+#  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+#  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+#  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+#  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+#  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+#  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+#  SOFTWARE.
+from flask import request
+from flask_restful import Resource
+from marshmallow import fields, Schema, validate
+from werkzeug.exceptions import BadRequest, Conflict
+
+from opendc.exts import requires_auth
+from opendc.models.scenario import Scenario
+
+
+def convert_to_job(scenario):
+    """Convert a scenario to a job.
+    """
+    return JobSchema().dump({
+        '_id': scenario['_id'],
+        'scenarioId': scenario['_id'],
+        'state': scenario['simulation']['state'],
+        'heartbeat': scenario['simulation'].get('heartbeat', None),
+        'results': scenario.get('results', {})
+    })
+
+
+class JobSchema(Schema):
+    """
+    Schema representing a simulation job.
+    """
+    _id = fields.String(dump_only=True)
+    scenarioId = fields.String(dump_only=True)
+    state = fields.String(required=True,
+                          validate=validate.OneOf(["QUEUED", "CLAIMED", "RUNNING", "FINISHED", "FAILED"]))
+    heartbeat = fields.DateTime()
+    results = fields.Dict()
+
+
+class JobList(Resource):
+    """
+    Resource representing the list of available jobs.
+    """
+    method_decorators = [requires_auth]
+
+    def get(self):
+        """Get all available jobs."""
+        jobs = Scenario.get_jobs()
+        data = list(map(convert_to_job, jobs.obj))
+        return {'data': data}
+
+
+class Job(Resource):
+    """
+    Resource representing a single job.
+    """
+    method_decorators = [requires_auth]
+
+    def get(self, job_id):
+        """Get the details of a single job."""
+        job = Scenario.from_id(job_id)
+        job.check_exists()
+        data = convert_to_job(job.obj)
+        return {'data': data}
+
+    def post(self, job_id):
+        """Update the details of a single job."""
+        action = JobSchema(only=('state', 'results')).load(request.json)
+
+        job = Scenario.from_id(job_id)
+        job.check_exists()
+
+        old_state = job.obj['simulation']['state']
+        new_state = action['state']
+
+        if old_state == new_state:
+            data = job.update_state(new_state)
+        elif (old_state, new_state) == ('QUEUED', 'CLAIMED'):
+            data = job.update_state('CLAIMED')
+        elif (old_state, new_state) == ('CLAIMED', 'RUNNING'):
+            data = job.update_state('RUNNING')
+        elif (old_state, new_state) == ('RUNNING', 'FINISHED'):
+            data = job.update_state('FINISHED', results=action.get('results', None))
+        elif old_state in ('CLAIMED', 'RUNNING') and new_state == 'FAILED':
+            data = job.update_state('FAILED')
+        else:
+            raise BadRequest('Invalid state transition')
+
+        if not data:
+            raise Conflict('State conflict')
+
+        return {'data': convert_to_job(data)}
diff --git a/opendc-web/opendc-web-api/opendc/database.py b/opendc-web/opendc-web-api/opendc/database.py
index 37fd1a4d..dd6367f2 100644
--- a/opendc-web/opendc-web-api/opendc/database.py
+++ b/opendc-web/opendc-web-api/opendc/database.py
@@ -20,7 +20,7 @@
 
 import urllib.parse
 
-from pymongo import MongoClient
+from pymongo import MongoClient, ReturnDocument
 
 DATETIME_STRING_FORMAT = '%Y-%m-%dT%H:%M:%S'
 CONNECTION_POOL = None
@@ -76,6 +76,12 @@ class Database:
         """Updates an existing object."""
         return getattr(self.opendc_db, collection).update({'_id': _id}, obj)
 
+    def fetch_and_update(self, query, update, collection):
+        """Updates an existing object."""
+        return getattr(self.opendc_db, collection).find_one_and_update(query,
+                                                                       update,
+                                                                       return_document=ReturnDocument.AFTER)
+
     def delete_one(self, query, collection):
         """Deletes one object matching the given query.
 
diff --git a/opendc-web/opendc-web-api/opendc/models/scenario.py b/opendc-web/opendc-web-api/opendc/models/scenario.py
index 658d790e..0fb6c453 100644
--- a/opendc-web/opendc-web-api/opendc/models/scenario.py
+++ b/opendc-web/opendc-web-api/opendc/models/scenario.py
@@ -1,15 +1,12 @@
+from datetime import datetime
+
 from marshmallow import Schema, fields
+
+from opendc.exts import db
 from opendc.models.model import Model
 from opendc.models.portfolio import Portfolio
 
 
-class SimulationSchema(Schema):
-    """
-    Simulation details.
-    """
-    state = fields.String()
-
-
 class TraceSchema(Schema):
     """
     Schema for specifying the trace of a scenario.
@@ -34,27 +31,6 @@ class OperationalSchema(Schema):
     schedulerName = fields.String()
 
 
-class ResultSchema(Schema):
-    """
-    Schema representing the simulation results.
-    """
-    max_num_deployed_images = fields.List(fields.Number())
-    max_cpu_demand = fields.List(fields.Number())
-    max_cpu_usage = fields.List(fields.Number())
-    mean_num_deployed_images = fields.List(fields.Number())
-    total_failure_slices = fields.List(fields.Number())
-    total_failure_vm_slices = fields.List(fields.Number())
-    total_granted_burst = fields.List(fields.Number())
-    total_interfered_burst = fields.List(fields.Number())
-    total_overcommitted_burst = fields.List(fields.Number())
-    total_power_draw = fields.List(fields.Number())
-    total_requested_burst = fields.List(fields.Number())
-    total_vms_failed = fields.List(fields.Number())
-    total_vms_finished = fields.List(fields.Number())
-    total_vms_queued = fields.List(fields.Number())
-    total_vms_submitted = fields.List(fields.Number())
-
-
 class ScenarioSchema(Schema):
     """
     Schema representing a scenario.
@@ -62,11 +38,9 @@ class ScenarioSchema(Schema):
     _id = fields.String(dump_only=True)
     portfolioId = fields.String()
     name = fields.String(required=True)
-    simulation = fields.Nested(SimulationSchema)
     trace = fields.Nested(TraceSchema)
     topology = fields.Nested(TopologySchema)
     operational = fields.Nested(OperationalSchema)
-    results = fields.Nested(ResultSchema, dump_only=True)
 
 
 class Scenario(Model):
@@ -84,3 +58,21 @@ class Scenario(Model):
         """
         portfolio = Portfolio.from_id(self.obj['portfolioId'])
         portfolio.check_user_access(user_id, edit_access)
+
+    @classmethod
+    def get_jobs(cls):
+        """Obtain the scenarios that have been queued.
+        """
+        return cls(db.fetch_all({'simulation.state': 'QUEUED'}, cls.collection_name))
+
+    def update_state(self, new_state, results=None):
+        """Atomically update the state of the Scenario.
+        """
+        update = {'$set': {'simulation.state': new_state, 'simulation.heartbeat': datetime.now()}}
+        if results:
+            update['$set']['results'] = results
+        return db.fetch_and_update(
+            query={'_id': self.obj['_id'], 'simulation.state': self.obj['simulation']['state']},
+            update=update,
+            collection=self.collection_name
+        )