Retainer

A simple script designed for CI with Portainer.

Configure in your project

Technically you can use this script in any kind of deploy scenario. This script is specially designed to work with Swarm services.

GitLab CI

Add some variables to your CI/CD configurations:

• PORTAINER_URL: (required) your Portainer address.
• PORTAINER_USERNAME: (required) a valid Portainer user.
• PORTAINER_PASSWORD: (required) the password for Portainer user.
• PORTAINER_NODES: (optional) a comma-separated list of Docker nodes, or an asterisk (*) for all nodes, or you can omit this variable and the script will pull the image in the default node.
• PORTAINER_ENDPOINT: (optional) the target Portainer endpoint, or you can omit this variable and the script will choose the first endpoint available.
• PYTHONUNBUFFERED: (optional) set any value for this variable to disable stdout and stderr buffering on Python.

Also, you need to embed the script as a file in your CI/CD configuration. Add a variable called RETAINER, select the "File" type and paste the Retainer script in the content field.

After that, you can use this example as a CI configuration:

stages:
  - build
  - deploy

# Build
build_image:
  only:
    - master
  image: docker:latest
  stage: build
  services:
    - docker:dind
  script:
    - export TAG=$(if [ $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH ]; then echo 'latest'; else echo $CI_COMMIT_BRANCH; fi)
    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
    - docker pull $CI_REGISTRY_IMAGE:$TAG
    - docker build -t $CI_REGISTRY_IMAGE:$TAG .
    - docker push $CI_REGISTRY_IMAGE:$TAG

# Deploy
portainer:
  only:
    - master
  image: alpine:latest
  stage: deploy
  script:
    - export TAG=$(if [ $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH ]; then echo 'latest'; else echo $CI_COMMIT_BRANCH; fi)
    - apk add py3-requests
    - python3 $RETAINER --image $CI_REGISTRY_IMAGE:$TAG

With this configuration, the CI will use some predefined variables of your project, build a default Dockerfile in the root of your project, and then deploy it on your Portainer.