Monorepo-diff-buildkite-plugin

This Monorepo plugin will assist you in triggering pipelines, as well as run commands in your CI by watching folders in your monorepo.

Check out this post to learn more about How to set up Continuous Integration for monorepo using Buildkite.

Usefulness of the monorepo

A monorepo is a single, version-controlled code repository that houses multiple independent projects, offering benefits such as flexibility, streamlined management, and reduced tracking of changes and dependencies across multiple repositories.

This approach allows teams to:

• Reduce overhead associated with duplicating code for microservices.
• Easily maintain and monitor the entire codebase.

Check out the example monorepo source code.

Using the plugin

If the version number is not provided then the most recent version of the plugin will be used. Do not use version number as master or any branch names.

watch

It defines a list of paths or path to monitor for changes in the monorepo. It checks to see if there is a change to the subfolders specified in the path

path

A path or a list of paths to be watched, This part specifies which directory should be monitored. It can also be a glob pattern. For example specify path: "**/*.md" to match all markdown files. A list of paths can be provided to trigger the desired pipeline or run command or even do a pipeline upload.

skip_path

A path or a list of paths to be ignored, which can be an exact path, or a glob.

This is intended to be used in conjunction with path, and allows omitting specific paths from being matched.

except_path

A path or a list of paths to prevent the paths listed to be matched, which can be an exact path, or a glob.

This is intended to be used in conjunction with path, and allows for creating exclusive matches with simpler rules when several files are modified in the same execution.

For example, in the following configuration:

steps:
  - label: "Triggering pipelines"
    plugins:
      - monorepo-diff#v1.4.0:
          watch:
            - path: "**/*"
              skip_path: "folder/file"
              config:
                trigger: "pipeline-1"
            - path: "**/*"
              except_path: "folder/file"
              config:
                trigger: "pipeline-2"
            - path: "folder/file"
              config:
                trigger: "pipeline-3"

If a single execution modified folder/file only pipeline-3 will be triggered. But if any other file is modified as well (thus matching **/*), pipeline-1 will also be triggered, but not pipeline-2.

config

This is a sub-section that provides configuration for running commands or triggering another pipeline when changes occur in the specified path. Configuration supports 3 different step types.

• Trigger
• Command
• Group

⚠️ This plugin may accept configurations that are not valid pipeline steps, this is a known issue to keep its code simple and flexible.

steps:
  - label: "Triggering pipelines"
    plugins:
      - monorepo-diff#v1.4.0:
          watch:
            - path: app/
              config:
                trigger: "app-deploy"
            - path: test/bin/
              config:
                command: "echo Make Changes to Bin"
            - path: docker/
              config:
                group: docker/**
                steps:
                  - plugins:
                      - docker#latest:
                          build: service
                          push: service
                  - command: docker/run-e2e-tests.sh

• Changes to the path app/ triggers the pipeline app-deploy
• Changes to the path test/bin will run the respective configuration command
• Changes to any file in the docker folder will run the steps in the group

⚠️ Warning : The user has to explictly state the paths they want to monitor or use wildcards. For instance if a user, is only watching path app/ changes made to app/bin will not trigger the configuration. This is because the subfolder /bin was not specified.

diff (optional)

This will run the script provided to determine the folder changes. Depending on your use case, you may want to determine the point where the branch occurs https://stackoverflow.com/questions/1527234/finding-a-branch-point-with-git and perform a diff against the branch point.

Default: git diff --name-only HEAD~1

Sample output:

README.md
lib/trigger.bash

Example scripts

diff: ./diff-against-last-successful-build.sh

#!/bin/bash

set -ueo pipefail

LAST_SUCCESSFUL_BUILD_COMMIT="$(aws s3 cp "${S3_LAST_SUCCESSFUL_BUILD_COMMIT_PATH}" - | head -n 1)"
git diff --name-only "$LAST_SUCCESSFUL_BUILD_COMMIT"

diff: ./diff-against-last-built-tag.sh

#!/bin/bash

set -ueo pipefail

LATEST_BUILT_TAG=$(git describe --tags --match foo-service-* --abbrev=0)
git diff --name-only "$LATEST_TAG"

interpolation (optional)

This controls the pipeline interpolation on upload, and defaults to true. If set to false it adds --no-interpolation to the buildkite pipeline upload, to avoid trying to interpolate the commit message, which can cause failures.

default (optional)

A default config to run if no paths are matched, the config key is not required, so a default can be written with a config attribute or simple just a command or trigger.

Example

steps:
  - label: "Triggering pipelines"
    plugins:
      - monorepo-diff#v1.4.0:
          watch:
            - path: "bar-service/"
              config:
                command: "echo deploy-bar"
            - path: "foo-service/"
              config:
                trigger: "deploy-foo-service"
            - default:
                config: ## <-- Optional
                  command: echo "Hello, world!"

env (optional)

The object values provided in this configuration will be appended to env property of all steps or commands.

steps:
  - label: "Triggering pipelines"
    plugins:
      - monorepo-diff#v1.4.0:
          watch:
            - path: "foo-service/"
              config:
                trigger: "deploy-foo-service"
                label: "Triggered deploy"
                build:
                  message: "Deploying foo service"
                  env:
                    - HELLO=123
                    - AWS_REGION

log_level (optional)

Add log_level property to set the log level. Supported log levels are debug and info. Defaults to info.

steps:
  - label: "Triggering pipelines"
    plugins:
      - monorepo-diff#v1.4.0:
          log_level: "debug" # defaults to "info"
          watch:
            - path: "foo-service/"
              config:
                trigger: "deploy-foo-service"

hooks (optional)

Currently supports a list of commands you wish to execute after the watched pipelines have been triggered

hooks:
  - command: upload unit tests reports
  - command: echo success

wait (optional)

Default: true

By setting wait to true, the build will wait until the triggered pipeline builds are successful before proceeding

Example

steps:
  - label: "Triggering pipelines"
    plugins:
      - monorepo-diff#v1.4.0:
          diff: "git diff --name-only $(head -n 1 last_successful_build)"
          interpolation: false
          env:
            - env1=env-1 # this will be appended to all env configuration
          hooks:
            - command: "echo $(git rev-parse HEAD) > last_successful_build"
          watch:
            - path:
                - "ops/terraform/"
                - "ops/templates/terraform/"
              config:
                command: "buildkite-agent pipeline upload ops/.buildkite/pipeline.yml"
                label: "Upload pipeline"
                # following configs are available in command. notify is not available in trigger step
                notify:
                  - basecamp_campfire: https://basecamp-url
                  - github_commit_status:
                      context: my-custom-status
                  - slack: "@someuser"
                    if: build.state === "passed"
                # soft_fail: true
                soft_fail:
                  - exit_status: 1
                  - exit_status: "255"
                retry:
                  automatic:
                    - limit: 2
                      exit_status: -1
                agents:
                  queue: performance
                artifacts:
                  - "logs/*"
                env:
                  - FOO=bar

          wait: true

Thanks ❤️

Thanks to @chronotc and @adikari for authoring the original Buildkite Monorepo Plugin.

License

MIT (see LICENSE)

How to Contribute

Please read contributing guide.