citus/src/test/regress/sql/failure_on_create_subscription.sql

--
-- failure_on_create_subscription
--

-- Since the result of these tests depends on the success of background
-- process that creating the replication slot on the publisher. These
-- tests are separated.

CREATE SCHEMA IF NOT EXISTS move_shard;
SET SEARCH_PATH = move_shard;
SET citus.shard_count TO 4;
SET citus.next_shard_id TO 100;
SET citus.shard_replication_factor TO 1;
SELECT pg_backend_pid() as pid \gset

SELECT citus.mitmproxy('conn.allow()');

CREATE TABLE t(id int PRIMARY KEY, int_data int, data text);

SELECT create_distributed_table('t', 'id');

CREATE VIEW shards_in_workers AS
SELECT shardid,
       (CASE WHEN nodeport = :worker_1_port THEN 'worker1' ELSE 'worker2' END) AS worker
FROM pg_dist_placement NATURAL JOIN pg_dist_node
WHERE shardstate != 4
ORDER BY 1,2 ASC;

-- Insert some data
INSERT INTO t SELECT x, x+1, MD5(random()::text) FROM generate_series(1,100000) AS f(x);

-- Initial shard placements
SELECT * FROM shards_in_workers;

-- Failure on creating the subscription
-- Failing exactly on CREATE SUBSCRIPTION is causing flaky test where we fail with either:
-- 1) ERROR:  connection to the remote node localhost:xxxxx failed with the following error: ERROR:  subscription "citus_shard_move_subscription_xxxxxxx" does not exist
-- another command is already in progress
-- 2) ERROR:  connection to the remote node localhost:xxxxx failed with the following error: another command is already in progress
-- Instead fail on the next step (ALTER SUBSCRIPTION) instead which is also required logically as part of uber CREATE SUBSCRIPTION operation.

SELECT citus.mitmproxy('conn.onQuery(query="ALTER SUBSCRIPTION").kill()');
SELECT master_move_shard_placement(101, 'localhost', :worker_1_port, 'localhost', :worker_2_proxy_port);

-- cleanup leftovers
SELECT citus.mitmproxy('conn.allow()');
SELECT public.wait_for_resource_cleanup();

SELECT citus.mitmproxy('conn.onQuery(query="ALTER SUBSCRIPTION").cancel(' || :pid || ')');
SELECT master_move_shard_placement(101, 'localhost', :worker_1_port, 'localhost', :worker_2_proxy_port);

-- Verify that the shard is not moved and the number of rows are still 100k
SELECT * FROM shards_in_workers;
SELECT count(*) FROM t;

-- Verify that shard can be moved after a temporary failure
-- cleanup leftovers, as it can cause flakiness in the following test files
SELECT citus.mitmproxy('conn.allow()');
SELECT public.wait_for_resource_cleanup();
SELECT master_move_shard_placement(101, 'localhost', :worker_1_port, 'localhost', :worker_2_proxy_port);
SELECT * FROM shards_in_workers;
SELECT count(*) FROM t;

DROP SCHEMA move_shard CASCADE ;