Allow semi-permanent selection of a subset of projects

🚀 Feature Proposal

Add the possibility to select a subset of the projects defined in .meta so that commands executed have an effect only on those.

Motivation

As a maintainer/developer of 50+ microservices, I have frequently the need to select and work only on a subset of those based on criteria X. This is a temporary filter that lasts only for the time needed to implement a feature, for example.

Example

In a meta-repository, the user could create a .meta-filter file that contains the projects to work on, either separated by a comma or new-line. Once this file is present, meta will apply all commands issued only to this subset of projects so that, for example, I can run npm install --save my-updated-library@new-version only in the projects I know need that update. Then I can commit and open a Merge Request via other commands for those repositories only. Once I am done I can remove the file and meta behaves normally.

[patrickleet]

you can also execute things inline

meta exec "npm install --save my-updated-library@new-version" --include-only=$(sh get-node-projects.sh)

I’ve done something like this in the past - created a script that returns each folder name that contains package.json - you could even grep for a particular package.

[patrickleet]

We’ve talked about something similar a few times.

I have frequently the need to select and work only on a subset of those based on criteria X. This is a temporary filter that lasts only for the time needed to implement a feature, for example.

FWIW, this can be accomplished with an environment variable in a single shell

export PROJECTS=one,two,three
meta git status --include-only=$PROJECTS

If you’re ok with changing the .meta file with current projects (which would be committed to git) may I suggest a workaround that you can use to accomplish this today?

Makefile

PROJECTS?=one,two,three
COMMAND?=git status

meta:
	meta $(COMMAND) --include-only=$(PROJECTS)

> COMMAND="exec pwd" make meta 
# command that's run: meta exec pwd --include-only=one,two,three

or

PROJECTS=one COMMAND="exec pwd" make meta

And when you want to change the default set you could update that in the Makefile.

I agree the syntax could be nicer by including it in meta, but I think it probably accomplishes the task.