cartodb-postgresql/scripts-available/CDB_GhostTables.sql
2019-03-06 18:20:04 +01:00

105 lines
3.4 KiB
PL/PgSQL

-- Table to store the transaction id from DDL events to avoid multiple executions
CREATE TABLE IF NOT EXISTS cartodb.cdb_ddl_execution(txid integer PRIMARY KEY);
-- Enqueues a job to run Ghost tables linking process for the provided user_id
CREATE OR REPLACE FUNCTION _CDB_LinkGhostTables(user_id text)
RETURNS void
AS $$
if not user_id:
return
client = GD.get('redis', None)
retry = 3
error = ''
redis_host = '127.0.0.1'
redis_port = 6379
redis_timeout = 5
while True:
if not client:
try:
import redis
client = GD['redis'] = redis.Redis(host=redis_host, port=redis_port, socket_timeout=redis_timeout)
except Exception as err:
error = "client_error - %s" % str(err)
# NOTE: no retries on connection error
plpy.error('Ghost tables connection error: ' + str(err))
break
try:
job = '{{"class":"Resque::UserDBJobs::UserDBMaintenance::LinkGhostTables","args":["{}"]}}'.format(user_id)
client.rpush("resque:queue:user_dbs", job)
break
except Exception as err:
error = "request_error - %s" % str(err)
client = GD['redis'] = None # force reconnect
if not retry:
plpy.error('Ghost tables error: ' + str(err))
break
retry -= 1 # try reconnecting
$$ LANGUAGE 'plpythonu' VOLATILE PARALLEL UNSAFE;
-- Enqueues a job to run Ghost tables linking process for the current user
CREATE OR REPLACE FUNCTION CDB_LinkGhostTables()
RETURNS void
AS $$
DECLARE
user_id TEXT;
BEGIN
EXECUTE 'SELECT (regexp_match(session_user, ''[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}''))[1];' INTO user_id;
PERFORM _CDB_LinkGhostTables(user_id);
DELETE FROM cartodb.cdb_ddl_execution WHERE txid = txid_current();
RAISE NOTICE '_CDB_LinkGhostTables(%) called', user_id;
END;
$$ LANGUAGE plpgsql VOLATILE PARALLEL UNSAFE SECURITY DEFINER;
-- Trigger function to call CDB_LinkGhostTables()
CREATE OR REPLACE FUNCTION _CDB_LinkGhostTablesTrigger()
RETURNS trigger
AS $$
BEGIN
PERFORM CDB_LinkGhostTables();
RETURN NULL;
END;
$$ LANGUAGE plpgsql VOLATILE PARALLEL UNSAFE SECURITY DEFINER;
-- Trigger to call CDB_LinkGhostTables() when adding a row in cartodb.cdb_ddl_execution
DROP TRIGGER IF EXISTS check_ddl_update ON cartodb.cdb_ddl_execution;
CREATE CONSTRAINT TRIGGER check_ddl_update
AFTER INSERT ON cartodb.cdb_ddl_execution
INITIALLY DEFERRED
FOR EACH ROW
EXECUTE PROCEDURE _CDB_LinkGhostTablesTrigger();
-- Event trigger to save the current transaction in cartodb.cdb_ddl_execution
CREATE OR REPLACE FUNCTION CDB_SaveDDLTransaction()
RETURNS event_trigger
AS $$
BEGIN
INSERT INTO cartodb.cdb_ddl_execution VALUES (txid_current()) ON CONFLICT (txid) DO NOTHING;
END;
$$ LANGUAGE plpgsql VOLATILE PARALLEL UNSAFE SECURITY DEFINER;
-- Creates the trigger on DDL events to link ghost tables
CREATE OR REPLACE FUNCTION CDB_EnableGhostTablesTrigger()
RETURNS void
AS $$
BEGIN
CREATE EVENT TRIGGER link_ghost_tables
ON ddl_command_end
WHEN TAG IN ('CREATE TABLE', 'SELECT INTO', 'DROP TABLE', 'ALTER TABLE', 'CREATE TRIGGER', 'DROP TRIGGER')
EXECUTE PROCEDURE CDB_SaveDDLTransaction();
END;
$$ LANGUAGE plpgsql VOLATILE PARALLEL UNSAFE;
-- Drops the trigger on DDL events to link ghost tables
CREATE OR REPLACE FUNCTION CDB_DisableGhostTablesTrigger()
RETURNS void
AS $$
BEGIN
DROP EVENT TRIGGER link_ghost_tables;
END;
$$ LANGUAGE plpgsql VOLATILE PARALLEL UNSAFE;