citus/src/test/regress/expected/failure_connection_establishment.out

--
-- failure_connection_establishment.sql tests some behaviour of connection management when
-- it fails to connect.
--
-- Failure cases covered:
--  - timeout
--
SELECT citus.mitmproxy('conn.allow()');
 mitmproxy 
-----------
 
(1 row)

CREATE SCHEMA fail_connect;
SET search_path TO 'fail_connect';
SET citus.shard_count TO 4;
SET citus.max_cached_conns_per_worker TO 0;
ALTER SEQUENCE pg_catalog.pg_dist_shardid_seq RESTART 1450000;
ALTER SEQUENCE pg_catalog.pg_dist_placement_placementid_seq RESTART 1450000;
CREATE TABLE products (
    product_no integer,
    name text,
    price numeric
);
SELECT create_distributed_table('products', 'product_no');
 create_distributed_table 
--------------------------
 
(1 row)

-- Can only add primary key constraint on distribution column (or group of columns
-- including distribution column)
-- Command below should error out since 'name' is not a distribution column
ALTER TABLE products ADD CONSTRAINT p_key PRIMARY KEY(name);
ERROR:  cannot create constraint on "products"
DETAIL:  Distributed relations cannot have UNIQUE, EXCLUDE, or PRIMARY KEY constraints that do not include the partition column (with an equality operator if EXCLUDE).
-- we will insert a connection delay here as this query was the cause for an investigation
-- into connection establishment problems
SET citus.node_connection_timeout TO 400;
SELECT citus.mitmproxy('conn.delay(500)');
 mitmproxy 
-----------
 
(1 row)

ALTER TABLE products ADD CONSTRAINT p_key PRIMARY KEY(product_no);
WARNING:  could not establish connection after 400 ms
ERROR:  connection error: localhost:9060
SELECT citus.mitmproxy('conn.allow()');
 mitmproxy 
-----------
 
(1 row)

CREATE TABLE r1 (
    id int PRIMARY KEY,
    name text
);
INSERT INTO r1 (id, name) VALUES
(1,'foo'),
(2,'bar'),
(3,'baz');
SELECT create_reference_table('r1');
NOTICE:  Copying data from local table...
 create_reference_table 
------------------------
 
(1 row)

SELECT citus.clear_network_traffic();
 clear_network_traffic 
-----------------------
 
(1 row)

SELECT citus.mitmproxy('conn.delay(500)');
 mitmproxy 
-----------
 
(1 row)

-- we cannot control which replica of the reference table will be queried and there is
-- only one specific client we can control the connection for.
-- by using round-robin task_assignment_policy we can force to hit both machines. We will
-- use two output files to match both orders to verify there is 1 that times out and falls
-- through to read from the other machine
SET citus.task_assignment_policy TO 'round-robin';
-- suppress the warning since we can't control which shard is chose first. Failure of this
-- test would be if one of the queries does not return the result but an error.
SET client_min_messages TO ERROR;
SELECT name FROM r1 WHERE id = 2;
 name 
------
 bar
(1 row)

SELECT name FROM r1 WHERE id = 2;
 name 
------
 bar
(1 row)

-- verify a connection attempt was made to the intercepted node, this would have cause the
-- connection to have been delayed and thus caused a timeout
SELECT citus.dump_network_traffic();
        dump_network_traffic         
-------------------------------------
 (0,coordinator,"[initial message]")
(1 row)

RESET client_min_messages;
-- verify get_global_active_transactions works when a timeout happens on a connection
SELECT get_global_active_transactions();
WARNING:  could not establish connection after 400 ms
WARNING:  connection error: localhost:9060
 get_global_active_transactions 
--------------------------------
(0 rows)

SELECT citus.mitmproxy('conn.allow()');
 mitmproxy 
-----------
 
(1 row)

DROP SCHEMA fail_connect CASCADE;
NOTICE:  drop cascades to 2 other objects
DETAIL:  drop cascades to table products
drop cascades to table r1
SET search_path TO default;