gitlab ci error could not translate host name "postgres" to address: Name does not resolve

Question

I use gitlab-ci in my rails app, it ran correctly till yesterday but it does not pass due to:

rake aborted!
PG::ConnectionBad: could not translate host name "postgres" to address: Name does not resolve
/usr/local/bundle/gems/pg-1.1.4/lib/pg.rb:56:in `initialize'
/usr/local/bundle/gems/pg-1.1.4/lib/pg.rb:56:in `new'
/usr/local/bundle/gems/pg-1.1.4/lib/pg.rb:56:in `connect'
....
Tasks: TOP => db:schema:load => db:check_protected_environments

.gitlab-ci.yml :

rspec:
  stage: test
  services:
    - postgres:10
  variables:
    DATABASE_URL: "postgresql://postgres:postgres@postgres:5432/$POSTGRES_DB"
    POSTGRES_DB: db_test
    RAILS_ENV: test
  before_script:
    - ruby -v
  script:
    - cp config/application.sample.yml config/application.yml
    - cp config/database.sample.yml config/database.yml
    - bundle exec rake db:schema:load
    - bundle exec rspec spec

It seems it can not find the postgres service running or for some reason the database service is not running correctly, I guess some internals has changed in gitlab-ci.

Answer 1

EDIT: This was an intended change to the images, you now must set a password or configure further:

If you know that you want to be insecure (i.e. any one can connect without a password from anywhere), then POSTGRES_HOST_AUTH_METHOD=trust is how you opt in to that.

---

This seems to have been introduced when the docker images were upgraded to the new releases.

You can pull the 10.11 image instead to avoid this problem for the time being:

services:
- postgres:10.11

Not sure why this is happening, but we are experiencing the same since the last docker image update. I have found this to also be the case going from 12.1 to 12.2.