Trying to connect GitLab-CE docker container to OpenLDAP docker container

I'm new to Docker and I'm trying to do something with Docker Networking. I have two containers, one is GitLab, and the other OpenLDAP, and I hope that I can get my Gitlab server to be setup with OpenLDAP authentication. I have the two composes below. The Gitlab compose is mainly copy and paste, as I'm not actually 100% sure on what the settings are supposed to be for the environment variables in order to have it communicate internally with the OpenLDAP container. I was hoping they could communicate entirely internally through a user-defined bridge called "loworkNetwork" I started before starting these composes.

Gitlab Docker-Compose

version: '2'

services:
  web:
    image: 'gitlab/gitlab-ce:latest'
    restart: always
    hostname: 'gitlab'
    environment:
      GITLAB_OMNIBUS_CONFIG: |
        external_url 'my_external_url'
        # These settings are documented in more detail at
        # https://gitlab.com/gitlab-org/gitlab-ce/blob/a0a826ebdcb783c660dd40d8cb217db28a9d4998/config/gitlab.yml.example#L136
        gitlab_rails['ldap_enabled'] = true
        gitlab_rails['ldap_host'] = 'ldap-service'
        gitlab_rails['ldap_port'] = 389
        gitlab_rails['ldap_uid'] = 'uid'
        gitlab_rails['ldap_method'] = 'plain' # 'ssl' or 'plain'
        gitlab_rails['ldap_bind_dn'] = 'cn=admin,dc=my_external_url,dc=com'
        gitlab_rails['ldap_password'] = 'password'
        gitlab_rails['ldap_allow_username_or_email_login'] = true
        gitlab_rails['ldap_base'] = 'dc=my_external_url,dc=com' 
    ports:
      - '80:80'
      - '443:443'
      - '22:22'
    volumes:
      - '/srv/gitlab/config:/etc/gitlab'
      - '/srv/gitlab/logs:/var/log/gitlab'
      - '/srv/gitlab/data:/var/opt/gitlab'
    networks:
      - loworkNetwork
networks:
  loworkNetwork:
    external: true

LDAP Services Docker-Compose

version: '2'

services:
  openldap:
    image: osixia/openldap:latest
    environment:
      - LDAP_ORGANISATION="lowork"
      - LDAP_DOMAIN=my_external_url
      - LDAP_ADMIN_PASSWORD=password
    networks:
      - loworkNetwork
    hostname: ldap-service

  phpldapadmin:
    image: osixia/phpldapadmin:latest
    ports:
      - "8080:80"
    environment:
      - PHPLDAPADMIN_LDAP_HOSTS=openldap
      - PHPLDAPADMIN_HTTPS=false
    networks:
      - loworkNetwork

networks:
  loworkNetwork:
    external: true

I've figured it out! In my case, all I had to do was change the host to the name of my container. So to in my gitlab docker-compose, I just changed the ldap-host to openldap because that's the name of my container.