porsager / postgres

Postgres.js - The Fastest full featured PostgreSQL client for Node.js, Deno, Bun and CloudFlare
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Issue with auto failover with CONNECT_TIMEOUT host #988

Open n3xt-kyle opened 4 days ago

n3xt-kyle commented 4 days ago

Related to but different than #815

const pgsql = postgres({
  host: "host1,host2,host3",
  port: 5432,
  user: "username",
  password: "password",
  database: "app",
  target_session_attrs: primary,
  max: 20,
  connect_timeout: 3
});

when host1 is offline, resulting in a CONNECT_TIMEOUT on the socket then the postgres client errors with the following and does not attempt to connect to host2 or host3:

Error: write CONNECT_TIMEOUT host1:5432
Stack: Error: write CONNECT_TIMEOUT host1:5432
    at connectTimedOut (node_modules/.pnpm/postgres@3.4.4/node_modules/postgres/cjs/src/connection.js:257:20)
    at Timeout.done [as _onTimeout] (node_modules/.pnpm/postgres@3.4.4/node_modules/postgres/cjs/src/connection.js:1033:8)
    at listOnTimeout (node:internal/timers:596:11)
    at process.processTimers (node:internal/timers:529:7)

when host1 is online, but not listening on port then the postgres library connects to host2 or host3, as appropriate based on primary session attrs.

when we change our config to only connect to host1 when it is not listening on port:

const pgsql = postgres({
  host: "host1",
  port: 5432,
  user: "username",
  password: "password",
  database: "app",
  max: 20,
});

we get the following error when trying to connect to the db via this postgres client library

Error:
Stack: AggregateError [ECONNREFUSED]:
    at internalConnectMultiple (node:net:1121:18)
    at internalConnectMultiple (node:net:1189:5)
    at afterConnectMultiple (node:net:1688:7)

It's as if ECONNREFUSED is handled in the desired way but CONNECT_TIMEOUT is not.

porsager commented 4 days ago

Do you think you can set up a failing test case ? (there's a limited amount of multi-host tests in the repo).