Drone supports launching detached service containers as part of your pipeline. The typical use case for services is when your unit tests require a running redis server, for example:

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kind: pipeline
type: docker
name: default

services:
- name: cache
  image: redis

Service containers are reachable at a hostname identical to the container name. In our previous example, the redis container name is cache, and can be accessed from the pipeline at tcp://cache:6379

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kind: pipeline
type: docker
name: default

steps:
- name: ping
  image: redis
  commands:
  - redis-cli -h cache ping

services:
- name: cache
  image: redis

It is important to note the service container exit code is ignored, and a non-zero exit code does not fail the overall pipeline. Drone expects service containers to exit with a non-zero exit code, since they often need to be killed after the pipeline completes.

Detached Steps

Services can also be defined directly in the pipeline, as detached pipeline steps. This can be useful when you need direct control over when the service is started, relative to other steps in your pipeline.

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kind: pipeline
name: default

steps:
- name: cache
  image: redis
  detach: true

- name: ping
  image: redis
  commands:
  - redis-cli -h cache ping

Common Problems

This section highlights some common problems that users encounter when configuring services. If you continue to experience issues please also check the faq. You might also want to compare your yaml to our example service configurations.

Incorrect Hostname

It is import to remember that you cannot use the localhost or 127.0.0.1 address to connect to services from your pipeline. Service containers are assigned their own IP address and hostname. The hostname is based on the service container name.

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kind: pipeline
type: docker
name: default

steps:
  - name: ping
    image: redis
    commands:
    - redis-cli -h cache ping

services:
  - name: cache
    image: redis

Initialization

It is important to remember that after a container is started, the software running inside the container (e.g. redis) takes time to initialize and begin accepting connections. There are two ways to handle this add a health check (prefered) or add a sleep.

Health check

Using a commandline tool to check if a service is up and running. This is a common idiom for webservers and also docker images. Below is an example for Mysql that uses the mysqladmin tool to check if the mysql server is running, then runs a sql command.

kind: pipeline
type: docker
name: default

steps:
  - name: mysql healthcheck
    image: mysql:5.7
    commands:
      - while ! mysqladmin ping -h mysql-server -u drone -pdrone --silent; do sleep 1; done
      - mysql -h mysql-server -u drone -pdrone -e "CREATE TABLE IF NOT EXISTS drone_db.pipelines (id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(50) NOT NULL);"

services:
  - name: mysql-server
    image: mysql:5.7
    environment:
      MYSQL_ALLOW_EMPTY_PASSWORD: yes
      MYSQL_DATABASE: drone_db
      MYSQL_USER: drone
      MYSQL_PASSWORD: drone

Here are some example health checks using http requests here. If however you are unable to craft a health check you can implement a sleep (see below).

Sleep

Be sure to give the service adequate time to initialize before attempting to connect. A naive solution is to use the sleep command.

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kind: pipeline
type: docker
name: default

steps:
  - name: ping
    image: redis
    commands:
    - sleep 5
    - redis-cli -h cache ping

services:
  - name: cache
    image: redis