New in Symplify 9: Monorepo Split with GitHub Action

2020-11-09

In past years, the split command was one of the poorest part of whole Symplify code base. Here is why.

In Symplify 9, we've finally fixed it - with a symplify/monorepo-split-github-action ↓

Battle Tested

We've been testing it last 3 weeks on 3 different monorepos. Nathan, good friend of mine, was eager to test them too on eonx-com monorepo.

This week, also Ruud Kamphuis pushed the package even further - thank you Ruud.

After dozens of successful GitHub Actions runs we're ready to go public - to you!

GitHub Actions - Composer for your CI

The idea of GitHub Actions is as simple as Composer or Dependency Injection: Do you need something? Ask for it.

If you're not yet familiar with GitHub Actions, give them a try. I first tried them almost a year ago, and every month I found something new to fell in love with.

The Simplest GitHub Action for 1 Package Split

Do you need a monorepo split? Ask for it:

# .github/workflows_monorepo_split.yaml
name: 'Monorepo Split'

on:
    push:
        branches:
            - main

jobs:
    monorepo_split:
        runs-on: ubuntu-latest

        steps:
            -   uses: actions/[email protected]

            -
                uses: "symplify/[email protected]"
                env:
                    GITHUB_TOKEN: ${{ secrets.ACCESS_TOKEN }}
                with:
                    # ↓ split "packages/easy-coding-standard" directory
                    package-directory: 'packages/easy-coding-standard'

                    # ↓ into https://github.com/symplify/easy-coding-standard repository
                    split-repository-organization: 'symplify'
                    split-repository-name: 'easy-coding-standard'

                    # ↓ the user signed under the split commit
                    user-name: "kaizen-ci"
                    user-email: "[email protected]"

The section with: is where you configure the output.

• package-directory is a local path to your split package, e.g. 'packages/easy-coding-standard'

• split-repository-organization and split-repository-name is name of repository on GitHub - basically symplify/easy-coding-standard

How to Split with Tags?

What is splitting good for without tags, right?

We need a tag, so we ask for it WyriHaximus/github-action-get-previous-tag:

 # .github/workflows_monorepo_split.yaml
 name: 'Monorepo Split'

 on:
     push:
         branches:
             - master

 jobs:
     monorepo_split:
         runs-on: ubuntu-latest

         steps:
             -
                 uses: actions/[email protected]
+                # this is required for "WyriHaximus/github-action-get-previous-tag" workflow
+                # see https://github.com/actions/checkout#fetch-all-history-for-all-tags-and-branches
+                with:
+                    fetch-depth: 0

+            # get a tag see https://github.com/WyriHaximus/github-action-get-previous-tag
+            -
+                id: previous_tag
+                uses: "WyriHaximus/github-action-get-p[email protected]"

            -
                uses: "symplify/[email protected]"
                env:
                    GITHUB_TOKEN: ${{ secrets.ACCESS_TOKEN }}
                with:
                    package-directory: 'packages/easy-coding-standard'
                    split-repository-organization: 'symplify'
                    split-repository-name: 'easy-coding-standard'

+                   tag: ${{ steps.previous_tag.outputs.tag }}

                    # ↓ the user signed under the split commit
                    user-name: "kaizen-ci"
                    user-email: "[email protected]"

How to Split Multiple Packages?

But wait, that's just one package. How can we do it for all 15 of them? Do we need 15 workflows files like this?

No, GitHub Actions are ready for this - add strategy section:

 ...
 jobs:
     monorepo_split:
         runs-on: ubuntu-latest

+        strategy:
+           fail-fast: false
+           matrix:
+               package:
+                    # list your packages here
+                    - easy-coding-standard
+                    - phpstan-rules

And update with: section with dynamic content:

                with:
-                   package-directory: 'packages/easy-coding-standard'
+                   package-directory: 'packages/${{ matrix.package }}'
                    split-repository-organization: 'symplify'
-                   split-repository-name: 'easy-coding-standard'
+                   split-repository-name: '${{ matrix.package }}'

This is a vast performance improvement, just like a parallel run.

Now GitHub Actions will run a standalone build for each package provided.

That's it!

How to migrate Symplify 8 to Symplify 9?

The split command was dropped in Symplify 9. Do you use it?

We've prepared a 3 step switch for you:

1. Remove directories_to_repositories parameter from monorepo-builder.(yaml|php):

 use Symfony\Component\DependencyInjection\Loader\Configurator\ContainerConfigurator;
 use Symplify\MonorepoBuilder\ValueObject\Option;

 return function (ContainerConfigurator $containerConfigurator): void {
     $parameters = $containerConfigurator->parameters();
-    $parameters->set(Option::DIRECTORIES_TO_REPOSITORIES, [
-        'packages/*' => '[email protected]:symplify/*.git',
-    ]);
};

2. Remove current split command from GitHub Action:

vendor/bin/monorepo-builder split

3. Add GitHub Action with a list of your packages in a matrix

Happy coding!