cartodb-postgresql/scripts-available/CDB_GhostTables.sql

121 lines
4.2 KiB
PL/PgSQL

-- Enqueues a job to run Ghost tables linking process for the provided username
CREATE OR REPLACE FUNCTION _CDB_LinkGhostTables(username text, db_name text, event_name text)
RETURNS void
AS $$
if not username:
return
if 'json' not in GD:
import json
GD['json'] = json
else:
json = GD['json']
tis_config = plpy.execute("select cartodb.CDB_Conf_GetConf('invalidation_service');")[0]['cdb_conf_getconf']
tis_config_dict = json.loads(tis_config) if tis_config else {}
tis_host = tis_config_dict.get('host', '127.0.0.1')
tis_port = tis_config_dict.get('port', 3142)
tis_timeout = tis_config_dict.get('timeout', 5)
tis_retry = tis_config_dict.get('retry', 5)
client = GD.get('invalidation', None)
while True:
if not client:
try:
import redis
client = redis.Redis(host=tis_host, port=tis_port, socket_timeout=tis_timeout)
GD['invalidation'] = client
except Exception as err:
error = "client_error - %s" % str(err)
# NOTE: no retries on connection error
plpy.warning('Invalidation Service connection error: ' + str(err))
break
try:
client.execute_command('DBSCH', db_name, username, event_name)
break
except Exception as err:
error = "request_error - %s" % str(err)
client = GD['invalidation'] = None # force reconnect
if not tis_retry:
plpy.warning('Invalidation Service error: ' + str(err))
break
tis_retry -= 1 # try reconnecting
$$ LANGUAGE 'plpythonu' VOLATILE PARALLEL UNSAFE;
-- Enqueues a job to run Ghost tables linking process for the current user
CREATE OR REPLACE FUNCTION CDB_LinkGhostTables(event_name text DEFAULT 'USER')
RETURNS void
AS $$
DECLARE
username TEXT;
db_name TEXT;
BEGIN
EXECUTE 'SELECT CDB_Username();' INTO username;
EXECUTE 'SELECT current_database();' INTO db_name;
PERFORM _CDB_LinkGhostTables(username, db_name, event_name);
RAISE NOTICE '_CDB_LinkGhostTables() called with username=%, event_name=%', username, event_name;
END;
$$ LANGUAGE plpgsql VOLATILE PARALLEL UNSAFE SECURITY DEFINER;
-- Trigger function to call CDB_LinkGhostTables()
CREATE OR REPLACE FUNCTION _CDB_LinkGhostTablesTrigger()
RETURNS trigger
AS $$
DECLARE
ddl_tag TEXT;
BEGIN
EXECUTE 'SELECT tag FROM cartodb.cdb_ddl_execution WHERE txid = txid_current();' INTO ddl_tag;
DELETE FROM cartodb.cdb_ddl_execution WHERE txid = txid_current();
PERFORM CDB_LinkGhostTables(ddl_tag);
RETURN NULL;
END;
$$ LANGUAGE plpgsql VOLATILE PARALLEL UNSAFE SECURITY DEFINER;
-- Event trigger to save the current transaction in cartodb.cdb_ddl_execution
CREATE OR REPLACE FUNCTION CDB_SaveDDLTransaction()
RETURNS event_trigger
AS $$
BEGIN
INSERT INTO cartodb.cdb_ddl_execution VALUES (txid_current(), tg_tag) ON CONFLICT (txid) DO NOTHING;
END;
$$ 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 $$
BEGIN
DROP EVENT TRIGGER IF EXISTS link_ghost_tables;
DROP TRIGGER IF EXISTS check_ddl_update ON cartodb.cdb_ddl_execution;
-- Table to store the transaction id from DDL events to avoid multiple executions
CREATE TABLE IF NOT EXISTS cartodb.cdb_ddl_execution(txid integer PRIMARY KEY, tag text);
CREATE CONSTRAINT TRIGGER check_ddl_update
AFTER INSERT ON cartodb.cdb_ddl_execution
INITIALLY DEFERRED
FOR EACH ROW
EXECUTE PROCEDURE _CDB_LinkGhostTablesTrigger();
CREATE EVENT TRIGGER link_ghost_tables
ON ddl_command_end
WHEN TAG IN ('CREATE TABLE', 'SELECT INTO', 'DROP TABLE', 'ALTER TABLE', 'CREATE TRIGGER', 'DROP TRIGGER', 'CREATE VIEW', 'DROP VIEW', 'ALTER VIEW')
EXECUTE PROCEDURE CDB_SaveDDLTransaction();
END;
$$ LANGUAGE plpgsql VOLATILE PARALLEL UNSAFE;
-- Drops the trigger on DDL events to link ghost tables
CREATE OR REPLACE FUNCTION CDB_DisableGhostTablesTrigger()
RETURNS void
AS $$
BEGIN
DROP EVENT TRIGGER IF EXISTS link_ghost_tables;
DROP TRIGGER IF EXISTS check_ddl_update ON cartodb.cdb_ddl_execution;
DROP TABLE IF EXISTS cartodb.cdb_ddl_execution;
END;
$$ LANGUAGE plpgsql VOLATILE PARALLEL UNSAFE;