Unable to get redis service to work in my CI

GitLab CI/CD
,
1

I have a fairly simple CI script with two stages. The first stage succeeds but the test stage fails with the following error.

Uncaught Error: Redis connection to redisio:6379 failed - getaddrinfo ENOTFOUND redisio redisio:6379
      at errnoException (dns.js:50:10)
      at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:92:26)

Any help would be appreciated.

Here is my script:

image: node:8.11.2

stages:
  - build
  - test
  - deploy

cache:
  paths:
    - node_modules/

install_deps:
  stage: build
  script:
    - yarn install
    - yarn lint

run_tests:
  stage: test
  script:
    - npm install -g mocha --save-dev
    - yarn install
    - yarn test
  services:
    - name: redis:5.0
      alias: redisio
    - name: mdillon/postgis:9.6
      alias: postgres
  variables:
    REDIS_HOST: redisio
    REDIS_PORT: 6379
    POSTGRES_SQL_HOST: postgres
    NODE_ENV: test
    POSTGRES_SQL_DATABASE: fluzfluz_backend_test
    POSTGRES_SQL_USER: test_user
    POSTGRES_SQL_PASSWORD: test_user_password
    POSTGRES_SQL_PORT: 5432
    # Necessary to setup the postgres service.
    POSTGRES_USER: test_user
    POSTGRES_PASSWORD: test_user_password
    POSTGRES_DB: fluzfluz_backend_test