def schedule_contract_invocation(
contract_model: "smart_contract_model.SmartContractModel",
action: SchedulerActions = SchedulerActions.CREATE) -> None:
"""Schedule cron smart contracts.
Call this method only after confirming sc_type is 'cron'
Args:
contract_model: a smart contract model which is type cron
Raises:
exceptions.TimingEventSchedulerError: when contract model is in a bad state
"""
if (action.value != "delete") and (contract_model.cron is None
and contract_model.seconds is None):
raise exceptions.TimingEventSchedulerError(
"You must provide cron or seconds to schedule a job")
redis.lpush_sync(
"mq:scheduler",
json.dumps(
{
"action": action.value,
"contract_id": contract_model.id,
"txn_type": contract_model.txn_type,
"execution_order": contract_model.execution_order,
"cron": contract_model.cron,
"seconds": contract_model.seconds,
},
separators=(",", ":"),
),
)
def update(self,
txn_type: Optional[str] = None,
execution_order: Optional[str] = None,
cron: Optional[str] = None,
seconds: Optional[int] = None) -> None:
"""Update this event instance
Args:
cron: cron expression string ex: "* * * * *"
seconds: integer of seconds between events. ex: 60
txn_type: updated transaction type to assign to this instance
execution_order: "serial" or "parallel
Raises:
exceptions.TimingEventSchedulerError<BAD_REQUEST> if no provided update parameters
"""
if (not cron and not seconds) or (
cron and seconds) or not execution_order or not txn_type:
raise exceptions.TimingEventSchedulerError("BAD_REQUEST")
if cron:
self.cron = cron
self.seconds = None
elif seconds:
self.seconds = seconds
self.cron = None
if txn_type:
self.txn_type = txn_type
if execution_order:
self.execution_order = execution_order
self.save()
background_scheduler.background_scheduler.reschedule_job(
self.id, trigger=self.get_trigger())
def parse_json_or_fail(json_str: Union[str, bytes]) -> Any:
"""
Common method for parsing json, and failing if malformed.
"""
try:
return json.loads(json_str)
except json.decoder.JSONDecodeError:
raise exceptions.TimingEventSchedulerError("MALFORMED_JSON")
def worker(change_request: dict) -> None:
"""Process incoming change requests
Args:
change_request: dict<ChangeRequest> {contract_id: string, action: SchedulerActions enum, seconds?:int, cron?: string}
"""
_log.debug(f"Change Request: {change_request}")
contract_id = change_request["contract_id"]
action = change_request["action"]
seconds = change_request.get("seconds")
cron = change_request.get("cron")
txn_type = change_request["txn_type"]
execution_order = change_request["execution_order"]
# Delete jobs
if action == "delete":
if not timing_event.exists(contract_id):
raise exceptions.TimingEventSchedulerError("NOT_FOUND")
event = timing_event.get_by_id(contract_id)
event.delete()
# Update job
if action == "update":
if not timing_event.exists(contract_id):
raise exceptions.TimingEventSchedulerError("NOT_FOUND")
event = timing_event.get_by_id(contract_id)
event.update(cron=cron,
seconds=seconds,
execution_order=execution_order,
txn_type=txn_type)
# Create new job
if action == "create":
event = timing_event.TimingEvent(cron=cron,
seconds=seconds,
timing_id=contract_id,
execution_order=execution_order,
txn_type=txn_type)
event.start()
_log.debug(f"Successful {action} on job '{contract_id}'")
def start(self) -> None:
"""Start this timing event's scheduler.
Raises:
exceptions.TimingEventSchedulerError<CONFLICT>: when a job with this ID already exists.
"""
self.save()
_log.debug("Job params successfully saved.")
try:
background_scheduler.background_scheduler.add_job(
self.submit_invocation_request,
max_instances=1,
trigger=self.get_trigger(),
id=self.id)
except ConflictingIdError:
raise exceptions.TimingEventSchedulerError("CONFLICT")
def get_by_id(timing_id: str) -> "TimingEvent":
"""Return a TimingEvent instance located by ID.
Args:
timing_id: The id of a running timing event. Usually a contract_id
Returns:
Instantiated timingEvent instance if found
Raises:
exceptions.TimingEventSchedulerError if event is not found
"""
result = redis.hget_sync(JOB_PARAMS_KEY, timing_id, decode=False)
if not result:
raise exceptions.TimingEventSchedulerError("NOT_FOUND")
params = json.loads(result)
return TimingEvent(timing_id=params["contract_id"],
seconds=params.get("seconds"),
cron=params.get("cron"))
class SchedulerTest(unittest.TestCase):
@patch("dragonchain.scheduler.scheduler.worker")
@patch("dragonchain.scheduler.scheduler.redis.delete_sync",
return_value="OK")
@patch("dragonchain.scheduler.scheduler.redis.lpush_sync",
return_value="OK")
@patch("dragonchain.scheduler.scheduler.redis.brpop_sync",
return_value=[
"whatever",
'{"action":"create","contract_id":"apples","seconds":60}'
])
def test_subscribe1(self, brpop, lpush, delete, mock_worker):
scheduler.subscribe("mq:scheduler")
mock_worker.assert_called_with({
"action": "create",
"contract_id": "apples",
"seconds": 60
})
@patch("dragonchain.scheduler.scheduler.worker",
side_effect=exceptions.TimingEventSchedulerError("boom"))
@patch("dragonchain.scheduler.scheduler.redis.delete_sync",
return_value="OK")
@patch("dragonchain.scheduler.scheduler.redis.lpush_sync",
return_value="OK")
@patch("dragonchain.scheduler.scheduler.redis.brpop_sync",
return_value=[
"whatever",
'{"action":"create","contract_id":"apples","seconds":60}'
])
def test_subscribe2(self, brpop, lpush, delete, mock_worker):
self.assertRaises(exceptions.TimingEventSchedulerError,
scheduler.subscribe, "mq:scheduler")
lpush.assert_called_with("mq:scheduler:errors", ANY)
@patch("dragonchain.scheduler.scheduler.redis.lpush_sync",
return_value="OK")
@patch("dragonchain.scheduler.scheduler.redis.hgetall_sync",
return_value={"banana": '{"contract_id":"banana","seconds":54}'})
def test_revive_dead_workers(self, hgetall, lpush):
scheduler.revive_dead_workers()
hgetall.assert_called_with("scheduler:params", decode=False)
lpush.assert_called_with(
"mq:scheduler",
'{"contract_id":"banana","seconds":54,"action":"create"}')
def test_parse_json_or_fail(self):
try:
scheduler.parse_json_or_fail("{{{{{}{}")
except Exception as e:
self.assertEqual(str(e), "MALFORMED_JSON")
return
self.fail() # Force a failure if no exception thrown
@patch("dragonchain.scheduler.scheduler.redis.lpush_sync")
def test_schedule_contract_invocation(self, lpush):
sc_model = MagicMock()
sc_model.id = "my_name"
sc_model.cron = "* * * * *"
sc_model.seconds = None
sc_model.txn_type = "banana"
sc_model.execution_order = "serial"
scheduler.schedule_contract_invocation(sc_model)
lpush.assert_called_with(
"mq:scheduler",
'{"action":"create","contract_id":"my_name","txn_type":"banana","execution_order":"serial","cron":"* * * * *","seconds":null}',
)
@patch("dragonchain.scheduler.scheduler.redis.lpush_sync")
def test_schedule_contract_invocation_raises(self, lpush):
sc_model = FakeScModel("my_name", None, None)
try:
scheduler.schedule_contract_invocation(sc_model)
self.fail("no error raised")
except Exception as e:
self.assertEqual(
str(e), "You must provide cron or seconds to schedule a job")
return
self.fail() # Force a failure if no exception thrown
# CREATE NON EXISTENT JOB
@patch("dragonchain.scheduler.timing_event.redis.hexists_sync",
return_value=False)
@patch("dragonchain.scheduler.timing_event.redis.hset_sync",
return_value="1")
def test_create_new_job(self, hset, hexists):
change_request = {
"action": "create",
"contract_id": "goo",
"txn_type": "banana",
"execution_order": "serial",
"cron": "* * * * *"
}
scheduler.worker(change_request)
hset.assert_called_with(
"scheduler:params", "goo",
'{"cron":"* * * * *","seconds":null,"contract_id":"goo","execution_order":"serial","txn_type":"banana"}'
)
# CREATE EXISTING JOB
@patch("dragonchain.scheduler.timing_event.redis.hset_sync")
@patch("dragonchain.scheduler.timing_event.redis.hexists_sync",
return_value=True)
@patch("apscheduler.schedulers.background.BackgroundScheduler.add_job",
side_effect=ConflictingIdError("goo"))
def test_create_existing_job(self, hexists, mock_hexists, mock_hset):
self.assertRaises(
exceptions.TimingEventSchedulerError,
scheduler.worker,
{
"action": "create",
"contract_id": "goo",
"txn_type": "banana",
"execution_order": "serial",
"cron": "* * * * *"
},
)
# DELETE EXISTING JOB
@patch("dragonchain.scheduler.timing_event.redis.hexists_sync")
@patch("dragonchain.scheduler.timing_event.redis.hget_sync",
return_value='{"contract_id":"goo","action":"delete","seconds":60}')
@patch("dragonchain.scheduler.timing_event.redis.hdel_sync")
@patch("apscheduler.schedulers.background.BackgroundScheduler.remove_job")
def test_delete_job(self, remove_job, hdel, hget, hexists):
change_request = {
"action": "delete",
"contract_id": "banana",
"txn_type": "banana",
"execution_order": "serial"
}
scheduler.worker(change_request)
remove_job.assert_called_once()
hdel.assert_called_once()
# DELETE NON EXISTENT JOB
@patch("dragonchain.scheduler.scheduler.timing_event.exists",
return_value=False)
@patch("dragonchain.scheduler.timing_event.redis.hget_sync",
return_value='{"contract_id":"goo","action":"delete","seconds":60}')
@patch("dragonchain.scheduler.timing_event.redis.hdel_sync")
@patch("apscheduler.schedulers.background.BackgroundScheduler.remove_job")
def test_delete_non_existent_job(self, remove_job, hdel, hget, exists):
change_request = {
"action": "delete",
"contract_id": "banana",
"txn_type": "banana",
"execution_order": "serial"
}
scheduler.worker(change_request)
remove_job.assert_not_called()
hdel.assert_not_called()
hget.assert_not_called()
# UPDATE
@patch("dragonchain.scheduler.scheduler.timing_event.exists",
return_value=True)
@patch(
"apscheduler.schedulers.background.BackgroundScheduler.reschedule_job")
@patch("dragonchain.scheduler.timing_event.redis.hget_sync",
return_value='{"contract_id":"whatever"}')
@patch("dragonchain.scheduler.timing_event.redis.hset_sync")
def test_update_job(self, mock_hset, mock_hget, reschedule_job, exists):
change_request = {
"action": "update",
"contract_id": "banana",
"execution_order": "serial",
"txn_type": "banana",
"seconds": 61
}
scheduler.worker(change_request)
reschedule_job.assert_called_with("whatever", trigger=ANY)
# UPDATE NON EXISTENT JOB
@patch("dragonchain.scheduler.scheduler.timing_event.exists",
return_value=False)
@patch(
"dragonchain.scheduler.scheduler.redis.hgetall_sync",
return_value={
"a":
'{"action":"update","contract_id":"goo","execution_order":"serial","txn_type":"banana",seconds":60}'
},
)
def test_update_non_existent_job(self, hgetall, hexists):
change_request = {
"action": "update",
"contract_id": "banana",
"execution_order": "serial",
"txn_type": "banana",
"seconds": 61
}
self.assertRaises(exceptions.TimingEventSchedulerError,
scheduler.worker, change_request)