def get_event_by_id(cursor, event_id):
cursor.execute(
"""
SELECT *
FROM events
WHERE id=%s
""",
[event_id],
)
return Event.from_dict(cursor.fetchone())
def get_next_event(cursor, topics):
LOGGER.debug("Getting next event for topics: %s", topics)
query = sql.SQL(
"""
SELECT *
FROM events
WHERE status='PENDING'
AND process_after < now()
AND topic in ({})
ORDER BY id
FOR UPDATE SKIP LOCKED
LIMIT 1
"""
).format(sql.SQL(", ").join(sql.Literal(topic) for topic in topics))
cursor.execute(query)
data = cursor.fetchone()
event = Event.from_dict(data) if data else None
LOGGER.debug("Next event: %s", event)
return event
def create_event(cursor, event):
LOGGER.debug("Creating event: %s", event)
# jsonb columns cannot handle certain data types without casting
# so make sure payload is always a JSON object by nesting it
payload = dict(payload=event.payload)
if event.process_after:
cursor.execute(
"""
INSERT INTO events (topic, payload, process_after)
VALUES (%s, %s, %s)
RETURNING *
""",
[event.topic, payload, event.process_after],
)
else:
cursor.execute(
"""
INSERT INTO events (topic, payload)
VALUES (%s, %s)
RETURNING *
""",
[event.topic, payload],
)
return Event.from_dict(cursor.fetchone())