Postgresql Docker role does not exist

Question

I downloaded the docker container for postgres: https://hub.docker.com/r/library/postgres/, and did the following:

$ docker run --name satgres -e POSTGRES_PASSWORD=mysecretpassword -d -p 5432:5432 postgres satgres | "docker-entrypoint.s…" | 5 seconds ago | Up 6 seconds | 0.0.0.0:5432->5432/tcp | satgres $ docker exec -it c8f1b22cc41e /bin/bash         # psql -U postgres psql (10.1) postgres=# CREATE DATABASE mytest; postgres=# \password postgres postgres=# CREATE ROLE ming WITH LOGIN PASSWORD 'pass1234'; postgres=# ALTER ROLE ming CREATEDB; postgres=# CREATE DATABASE sjk; postgres=# GRANT ALL PRIVILEGES ON DATABASE youtube TO ming; postgres=# \connect sjk youtube=# ALTER ROLE ming lOGIN;   

My plan is to use this database on docker with Django, so first want to check I can connect, but I cant.

$ psql -h localhost -p 5432 -U postgres $ psql: FATAL:  role "postgres" does not exist $ psql -h localhost -p 5432 -U ming $ psql: FATAL:  role "ming" does not exist 

I do the same with PSequal.app, says the same thing, Im running on Mac High Sierra.

Why am I getting this error? The role exists, or at least it seems it to me...

Answer 1

The problem was simple enough that my computer was already running an instance of Postgres that I was not aware was still running (not inside Docker) on :5432, checked with:

$ lsof -n -i:5432 | grep LISTEN 

So I remembered I installed it via https://gist.github.com/sgnl/609557ebacd3378f3b72, I ran

$ pg-stop 

And then I had no problem connecting to the Docker instance.

Edit (2019/07/02)

This question recently passed 10,000 views, so I thought I should elaborate more on why this happened.

Usually running through docker, using python and connecting to a postgres database requires you to install psycopg2, via pip3 install psycopg2, but if you run this command you will get:

Error: pg_config executable not found. 

This is because psycopg2 requires an operating system install of the postgres libraries:

yum install postgresql-devel apt-get install postgresql-client 

Now, on a Mac, you will need to do the same with brew:

brew install postgresql 

One thing that I didn't realise, is that on Mac, doing the above will not only install required libraries, but also start a database on :5432. Because this was all done in the background, it didn't occur to me that this was the problem as none of the usual errors popped up to inform that the port was being used, etc...

Answer 2

In my case, the problem may be due also to the use of a super user who is not postgres. Lhe developers chose the user georchestra in the geOrchestra docker composition. Extract from the dockerfile:

environment:   - POSTGRES_USER=georchestra  HEALTHCHECK --interval=30s --timeout=30s \   CMD pg_isready -U $POSTGRES_USER 

consequently, you will have to use the option "-U georchestra" to connect to the container.

$ docker exec -it docker_database_1 psql -U georchestra psql (10.5 (Debian 10.5-1.pgdg90+1)) Type "help" for help. 

and of course, trying to connect with the user postgres causes an error:

docker exec -it docker_database_1 psql -U postgres psql: FATAL:  role "postgres" does not exist