# Build config variables
# Overview
Build config variables are defined by the build container config in your .sun-ci.yml file.
Environment variables are defined using the environment keyword.
jobs:
build:
image: node
environment:
NODE_ENV: production
script:
- echo $NODE_ENV # production
# Service container environment variables
You can also define environment variables for service containers. A lot of docker images use environment variables to customize the application running inside the container.
Environment variables in service containers are defined the same way as the build container.
For example, to customize the MySQL service for a Laravel application:
jobs:
test:
services:
- image: mysql:8
name: mysql-test
environment:
MYSQL_DATABASE: my_app
MYSQL_USER: my_app
MYSQL_PASSWORD: secret
image: php
environment:
DB_HOST: mysql
DB_PORT: 3306
DB_DATABASE: my_app
DB_USERNAME: my_app
DB_PASSWORD: secret
# Syntax
There are two syntaxes available for defining your environment variables.
# Array of variable defines
jobs:
build:
image: node
environment:
- NODE_ENV=production
# Use YAML mapping
jobs:
build:
image: node
environment:
NODE_ENV: production
This syntax is particularly useful when you want to use YAML anchor to merge environment variables.
# Global variables
You can define variables available to all jobs using the default config.
In the following example, $NODE_ENV is available in all jobs in the build.
default:
environment:
NODE_ENV: production
jobs:
install:
stage: install
image: node
script:
- echo $NODE_ENV # production
Global variables can be overriden by job-defined environment variables.
default:
environment:
NODE_ENV: production
jobs:
install:
stage: install
image: node
environment:
NODE_ENV: development
script:
- echo $NODE_ENV # development
- npm install
build:
stage: build
image: node
script:
- echo $NODE_ENV # production
- npm run build
In the above example, $NODE_ENV is set to development in the job install. Job build still has NODE_ENV=production.