Trigger build step based on modified directory

Drone Support
1

Hi everyone
Is it any way to skip build step based on which directories were changed by commit?

I can’t find anything related here
http://readme.drone.io/usage/skipping-build-steps

Consider this structure of the project that called ‘MyApp’

MyApp
  .drone.yml
  service1/
      Dockerfile
  service2/         # I want to trigger build only of this service only if commit modified files there
     Dockerfile
  service3/
     Dockerfile

It would be extremely useful for projects with Monorepository which has multiple services with Dockerfiles in it. So we could build only images with modified code instead of useless rebuilding of already up-to-date ones.

2

this is not currently possible. There is an open issue for this, however, the full set of requirements and scope are not yet well defined and could use help https://github.com/drone/drone/issues/1021

3

Hey there,

I had a similar requirement the past days - we need to build custom php docker images for our unit tests (which require some additional modules). I solved it by using the build matrix and building a Dockerfile when required for the step.

pipeline:
  prepare:
    image: alpine:3.4
    commands:
      - export PHP_BASE_TAG=${PHP_BASE_TAG}
      - ./prepare_build.sh

  docker:
    image: drone/plugin-docker
    registry: docker.solutiondrive.de
    username: ${DOCKER_USERNAME}
    password: ${DOCKER_PASSWORD}
    email: ${DOCKER_EMAIL}
    repo: registry/library/php-xdebug
    tags: ${DOCKER_TAGS}
    file: Dockerfile
    when:
      branch: master
      event: push

matrix:
  include:
    # php 7.1 series
    - PHP_BASE_TAG: 7.1.4-alpine
      DOCKER_TAGS: 7.1, 7.1.4
      # 7.0 series
    - PHP_BASE_TAG: 7.0.18-alpine
      DOCKER_TAGS: 7.0, 7.0.18

#!/bin/sh
echo "FROM php:${PHP_BASE_TAG}" > Dockerfile
cat Dockerfile.template >> Dockerfile

I realize it is not as convenient as watching a file - but it works and in our case it`s already useful.

If you need it on a file watch basis - you could easily write a docker plugin that does this for you. Iterare through the files in your repository - if the file is called Dockerfile , make a hash of it’s contents - store the hash “somewhere” and on the next run compare the hash with the stored one

4

Thanks we’ll try it!