Checkout: Why the git 2.18 is required, there is no explanation in README

[phadej]

As Ubuntu LTS-18.04 ships git-1.17.1 this is a frustrating limitation, as one needs to update git in virtually any docker container used, when you care about having .git folder present.

[ericsciple]

Checkout v2 was optimized to fetch a single commit - requires Git wire protocol v2.

[phadej]

Is the alternative to use raw git clone + git checkout commands if I want to use github actions on as vanilla Ubuntu LTS images as possible?

EDIT: We are testing git integration, so it's actually desirable to also use older versions. Does GitHub have any stats what versions of clients is used to access the site?

[stevehobbsdev]

@phadej Can I ask how you are updating Git?

I'm using the circleci/ruby:2.4.1-node-browsers docker image, and I'm using the following commands:

sudo apt-get install python-software-properties software-properties-common
sudo add-apt-repository ppa:git-core/ppa -y
sudo apt-get update
sudo apt-get install git -y
git --version

But this fails:

Err http://http.us.debian.org jessie-backports/main Sources
  404  Not Found [IP: 64.50.233.100 80]

I'm having to do this because actions/checkout fails on my build with the error (using Git 2.1.4):

##[error]EACCES: permission denied, open '/__w/ocs-website-rebuild/ocs-website-rebuild/577d8b45-e925-465b-9cc8-5831813609ad.tar.gz'

I'm assuming that if I can upgrade it to 2.18 then it can just do a normal git clone and not have to download a TGZ file (getting around the permissions issue). But my assumptions might be way off.

[phadej]

@stevehobbsdev PPA works only with Ubuntu, and jessie is Debian.

I currently use

      - name: Checkout
        run: |
          git clone --depth 1 https://github.com/$GITHUB_REPOSITORY.git .
          git fetch origin $GITHUB_REF:temporary-ci-branch
          git checkout $GITHUB_SHA

step. It seems to work, but I'm quite sure I'm missing something.

[tariqc80]

I'm experiencing this issue too.

Checkout v2 was optimized to fetch a single commit - requires Git wire protocol v2.

@ericsciple The benefit of fetching a single commit clone is lost when using the ubuntu-latest image, which is widely used. Instead of a file sync when the git version is < 2.18, it would be convenient if the plugin performed a shallow clone of a single branch. This is supported in 2.11 with the --depth 1 and --branch options

[ericsciple]

@tariqc80 ubuntu-latest has git version 2.26.0

Here is my workflow:

on: push
jobs:
  build:
    runs-on: [ubuntu-latest]
    steps:
      - run: git --version

Using branch + depth 1 is a race condition. The ref may move forward before the job begins, especially in workflows with a graph of jobs.

[ericsciple]

...which is why checkout@v2 fetches the SHA instead

[tariqc80]

@ericsciple Thanks for the response. I didn't realize that the job I was working with was using a container built from Debian Stretch; which ships with git v2.11.

Now I understand the difference between runs-on and container. Updating the git version in the container got me working correctly.