Can't run pg in docker - postgresql

Question

When I try to start a container like this:
db:
container_name: database-pg
image: postgres
ports:
- 127.0.0.1:5432:5432
restart: always
logging:
<<: *logging_default
volumes:
- datavolume:/var/lib/postgresql/data
- ./backend/db/migrations/0001-init.up.sql:/docker-entrypoint-initdb.d/0001-init.up.sql
- ./envs/ropsten/seed.sql:/docker-entrypoint-initdb.d/0002-seed.sql
environment:
- POSTGRES_PASSWORD=postgres
- POSTGRES_USER=postgres
- POSTGRES_HOST_AUTH_METHOD=trust
I see this:
2021-01-09 12:00:48.362 UTC [89] FATAL: password authentication failed for user "postgres"
2021-01-09 12:00:48.362 UTC [89] DETAIL: Password does not match for user "postgres".
Connection matched pg_hba.conf line 99: "host all all all md5"
2021-01-09 12:01:47.477 UTC [91] FATAL: password authentication failed for user "postgres"
2021-01-09 12:01:47.477 UTC [91] DETAIL: Password does not match for user "postgres".
Connection matched pg_hba.conf line 99: "host all all all md5"
2021-01-09 12:01:47.909 UTC [92] FATAL: password authentication failed for user "postgres"
2021-01-09 12:01:47.909 UTC [92] DETAIL: Password does not match for user "postgres".
Connection matched pg_hba.conf line 99: "host all all all md5"
2021-01-09 12:01:47.988 UTC [93] FATAL: password authentication failed for user "postgres"
2021-01-09 12:01:47.988 UTC [93] DETAIL: Password does not match for user "postgres".
Connection matched pg_hba.conf line 99: "host all all all md5"
2021-01-09 12:01:48.540 UTC [94] FATAL: password authentication failed for user "postgres"
2021-01-09 12:01:48.540 UTC [94] DETAIL: Password does not match for user "postgres".
Connection matched pg_hba.conf line 99: "host all all all md5"
2021-01-09 12:01:48.627 UTC [95] FATAL: password authentication failed for user "postgres"
2021-01-09 12:01:48.627 UTC [95] DETAIL: Password does not match for user "postgres".
Connection matched pg_hba.conf line 99: "host all all all md5"
I cannot understand why this is happening. Why does postgres show this error at all, what else should the password be at startup.

Answer 1

I've tried to run postgres using your configuration (I've just removed the logging and volumes section) and everything was fine.
It seems to me that you put the POSTGRES_HOST_AUTH_METHOD=trust config after initializing the database. There is a note in the official docker image readme:
This optional variable can be used to control the auth-method for host connections for all databases, all users, and all addresses. If unspecified then md5 password authentication is used. On an uninitialized database, this will populate pg_hba.conf via this approximate line:
echo "host all all all $POSTGRES_HOST_AUTH_METHOD" >> pg_hba.conf
So, to fix your problem you should either delete your data and recreate the database or mount your own updated pg_hba.conf file:
version: '3'
services:
db:
container_name: database-pg
image: postgres
ports:
- 127.0.0.1:5433:5432
restart: always
environment:
- POSTGRES_PASSWORD=postgres
- POSTGRES_USER=postgres
- POSTGRES_HOST_AUTH_METHOD=trust
command: postgres -c 'hba_file=/var/lib/postgresql/pg_hba.conf'
volumes:
- datavolume:/var/lib/postgresql/data
- ./backend/db/migrations/0001-init.up.sql:/docker-entrypoint-initdb.d/0001-init.up.sql
- ./envs/ropsten/seed.sql:/docker-entrypoint-initdb.d/0002-seed.sql
- ./hba.conf:/var/lib/postgresql/pg_hba.conf
where hba.conf:
# "local" is for Unix domain socket connections only
local all all trust
# IPv4 local connections:
host all all 127.0.0.1/32 trust
# IPv6 local connections:
host all all ::1/128 trust
# Allow replication connections from localhost, by a user with the
# replication privilege.
local replication all trust
host replication all 127.0.0.1/32 trust
host replication all ::1/128 trust
# warning trust is enabled for all connections
# see https://www.postgresql.org/docs/12/auth-trust.html
host all all all trust