CNB

Build Environment

The build environment determines which software is available in the environment when running build tasks.

Cloud Native Build uses Docker containers as the build environment.

Compared to traditional virtual machine containers, Docker containers have significant advantages, and various CI vendors in the industry are also moving in this direction.

When using Cloud Native Build, make sure you have experience using Docker containers or at least have a basic understanding of Docker fundamentals.

# Configuration Methods

There are two ways to configure Docker containers:

  1. Specify an image (existing image). These images have been created by others and pushed to a container registry.
  2. Specify a Dockerfile. Cloud Native Build will use the Dockerfile to build the
  3. image on-the-fly (or use cache under certain conditions) during the build process.

# Specify an Image

main:
  push:
    - docker:
        # Specify the image to use with this parameter
        image: node:22
      stages:
        - stage1
        - stage2
        - stage3

Specify the Docker image using the pipeline.docker.image parameter. Its value can be a public image from the official image repository in the public network or other accessible image sources.

# Specify a Dockerfile

main:
  push:
    - docker:
        # Specify the Dockerfile to use with this parameter
        build: ./image/Dockerfile
      stages:
        - stage1
        - stage2
        - stage3

Specify the Dockerfile using the pipeline.docker.build parameter.

# VOLUME in the Image

The image may contain VOLUME commands. When the image task container starts, these volumes are shared with the image task using the --volumes-from parameter.

For example, if the Dockerfile prepares a file:

RUN mkdir /cache && echo '[{"author_email": "git_user1@xxx.com"}]' > /cache/cache.json

VOLUME /cache

It can be accessed in subsequent image-commands as well.

- name: Access pipeline volume in image-commands
  image: alpine
  commands:
    - cat /cache/cache.json

# Default Image

If neither of the above methods is specified, the default value cnbcool/default-build-env:latest will be used.

# Use Cases

# NodeJS

When you need to use the NodeJS build environment, you can directly use the official NodeJS image from Docker Hub.

main:
  push:
    - docker:
        image: node:16
      stages:
        - name: Install Dependencies
          script: npm install
        - name: Run Test Cases
          script: npm test