lerna publish from-package fails in AWS CodeBuild

[samlecuyer]

AWS CodePipeline does not provide the .git directory or git executable to CodeBuild jobs, even when sourcing the code from a CodeCommit repository. The step to add gitHead to each package fails and cannot publish due to the error.

Expected Behavior

lerna should be able to publish in a non-git environment using from-package

Current Behavior

> lerna publish from-package --no-git-reset
 lerna notice cli v3.11.1
lerna ERR! ENOGIT The git binary was not found, or this is not a git repository.

Possible Solution

Maybe make the gitHead step optional or fail silently in non-git environments.

Steps to Reproduce (for bugs)

1. Create a monorepo with at least one package
2. Remove git from your path and .git, if any exist
3. lerna publish from-package

lerna.json

{
  "packages": [
    "packages/*"
  ],
  "version": "0.1.0"
}

Context

I'm investigating using a monorepo with our existing infrastructure, which is AWS. We cannot use lerna with AWS Developer Tools unless it can publish gitless. I do not expect version to work without git (that should be done by people on their dev machines), but publish should.

Your Environment

Running in AWS CodeBuild, Ubuntu, Node.JS 10.14.1.

Executable	Version
lerna --version	v3.11.1
npm --version	6.7.0
yarn --version	VERSION
node --version	10.14.1

[samlecuyer]

Digging into the CodeBuild docs, it looks like there's a CODEBUILD_SOURCE_VERSION env var that's passed to the build job. A possible solution to this might also be to allow a hash to be passed so that the publish step doesn't need git.

lerna publish from-package --with-git-head 44d86a1...

[evocateur]

Yep, that certainly makes sense. A similar approach to #1908 is what I'm thinking (noodling locally right now). There are a couple more places we need to be aware of "do i need git", but it's actually not bad.

I think a (simplified) --git-head option would be a nice DX improvement, to preserve the gitHead metadata available from the registry.

[evocateur]

@samlecuyer How does this look?

[samlecuyer]

@evocateur this is amazing, thank you for being so responsive! API-wise, it looks good to me