redis

pig build pkg pg_redis_pubsub;		# build rpm/deb

pig repo add pgsql -u   # add both repo and update cache

pig install pg_redis_pubsub;		# install via package name, for the active PG version
pig install redis;		# install by extension name, for the current active PG version

pig install redis -v 18;   # install for PG 18
pig install redis -v 17;   # install for PG 17
pig install redis -v 16;   # install for PG 16
pig install redis -v 15;   # install for PG 15
pig install redis -v 14;   # install for PG 14

CREATE EXTENSION redis;

ALTER SYSTEM SET redis.host = '127.0.0.1';
ALTER SYSTEM SET redis.port = '6379';
SELECT pg_reload_conf();

SET redis.host = '127.0.0.1';
SET redis.port = '6379';

CREATE EXTENSION redis;

SELECT redis_connect();
SELECT redis_publish('mychannel', 'Hello World');
SELECT redis_disconnect();

CREATE OR REPLACE FUNCTION notify_changes()
RETURNS TRIGGER AS $$
BEGIN
  PERFORM redis_publish(
    'products:' || NEW.id::text,
    to_jsonb(NEW)::text
  );
  RETURN NULL;
END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER on_product_change
  AFTER INSERT OR UPDATE ON products
  FOR EACH ROW EXECUTE PROCEDURE notify_changes();