'How to get the current branch within Github Actions?
I'm building Docker images with Github Actions and want to tag images with the branch name.
I found the GITHUB_REF
variable, but it results in refs/heads/feature-branch-1
and I need only feature-branch-1
.
Solution 1:[1]
I added a separate step for extracting branch name from $GITHUB_REF
and set it to the step output
- name: Extract branch name
shell: bash
run: echo "##[set-output name=branch;]$(echo ${GITHUB_REF#refs/heads/})"
id: extract_branch
after that, I can use it in the next steps with
- name: Push to ECR
id: ecr
uses: jwalton/gh-ecr-push@master
with:
access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
region: us-west-2
image: eng:${{ steps.extract_branch.outputs.branch }}
Solution 2:[2]
I believe GITHUB_REF
is the only environment variable that includes the branch name.
You can extract just the branch name from the rest of that string like this:
${GITHUB_REF##*/}
Example:
$ GITHUB_REF=refs/heads/feature-branch-1
$ echo ${GITHUB_REF##*/}
feature-branch-1
Update: Added a complete workflow example.
Workflow
name: CI
on: push
jobs:
build:
runs-on: ubuntu-latest
steps:
- name: Git checkout
uses: actions/checkout@v1
- name: Branch name
run: echo running on branch ${GITHUB_REF##*/}
- name: Build
run: docker build -t tedmiston/tag-example:${GITHUB_REF##*/} .
Source: https://github.com/tedmiston/x/blob/master/.github/workflows/workflow.yml
Sample output - master branch
Run docker build -t tedmiston/tag-example:${GITHUB_REF##*/} .
docker build -t tedmiston/tag-example:${GITHUB_REF##*/} .
shell: /bin/bash -e {0}
Sending build context to Docker daemon 146.9kB
Step 1/1 : FROM alpine
latest: Pulling from library/alpine
9d48c3bd43c5: Pulling fs layer
9d48c3bd43c5: Verifying Checksum
9d48c3bd43c5: Download complete
9d48c3bd43c5: Pull complete
Digest: sha256:72c42ed48c3a2db31b7dafe17d275b634664a708d901ec9fd57b1529280f01fb
Status: Downloaded newer image for alpine:latest
---> 961769676411
Successfully built 961769676411
Successfully tagged tedmiston/tag-example:master
Log: https://github.com/tedmiston/x/commit/cdcc58a908e41d3d90c39ab3bf6fef1ad2c4238a/checks#step:4:16
Sample output - non-master branch
Run docker build -t tedmiston/tag-example:${GITHUB_REF##*/} .
docker build -t tedmiston/tag-example:${GITHUB_REF##*/} .
shell: /bin/bash -e {0}
Sending build context to Docker daemon 144.9kB
Step 1/1 : FROM alpine
latest: Pulling from library/alpine
9d48c3bd43c5: Pulling fs layer
9d48c3bd43c5: Verifying Checksum
9d48c3bd43c5: Download complete
9d48c3bd43c5: Pull complete
Digest: sha256:72c42ed48c3a2db31b7dafe17d275b634664a708d901ec9fd57b1529280f01fb
Status: Downloaded newer image for alpine:latest
---> 961769676411
Successfully built 961769676411
Successfully tagged tedmiston/tag-example:branch-name-test
Log: https://github.com/tedmiston/x/commit/4e8d31259f861aaa2c30375756fc081c3659bddf/checks#step:4:16
See this answer for more on parameter expansion syntax.
For reference the page Virtual environments for GitHub Actions lists all of the environment variables available in the execution environment.
Solution 3:[3]
Be aware that if you are executing your GitHub action on pull request trigger, then GITHUB_REF
variable will contain something like refs/pull/421/merge
so if you will try to git push
to that name it will most likely fail.
What you can use though are references on the GitHub context in your YAML. Something like: ${{ github.head_ref }}
Solution 4:[4]
Using setenv
is now deprecated. It is advised to use environment files. Building on @youjin's answer, while still allowing feature/
branches (replacing all occurences of /
with -
), I am now using this:
jobs:
build:
runs-on: ubuntu-latest
steps:
- name: Get branch name (merge)
if: github.event_name != 'pull_request'
shell: bash
run: echo "BRANCH_NAME=$(echo ${GITHUB_REF#refs/heads/} | tr / -)" >> $GITHUB_ENV
- name: Get branch name (pull request)
if: github.event_name == 'pull_request'
shell: bash
run: echo "BRANCH_NAME=$(echo ${GITHUB_HEAD_REF} | tr / -)" >> $GITHUB_ENV
- name: Debug
run: echo ${{ env.BRANCH_NAME }}
Solution 5:[5]
You could use https://github.com/rlespinasse/github-slug-action
# Just add this =>
- name: Inject slug/short variables
uses: rlespinasse/[email protected]
# And you get this =>
- name: Print slug/short variables
run: |
echo "Slug variables"
echo " - ${{ env.GITHUB_REF_SLUG }}"
echo " - ${{ env.GITHUB_HEAD_REF_SLUG }}"
echo " - ${{ env.GITHUB_BASE_REF_SLUG }}"
echo " - ${{ env.GITHUB_REPOSITORY_SLUG }}"
# output e.g. : master feat-new-feature v1.0.0 product-1.0.0-rc.2 new-awesome-product
echo "Slug URL variables"
echo " - ${{ env.GITHUB_REF_SLUG_URL }}"
echo " - ${{ env.GITHUB_HEAD_REF_SLUG_URL }}"
echo " - ${{ env.GITHUB_BASE_REF_SLUG_URL }}"
echo " - ${{ env.GITHUB_REPOSITORY_SLUG_URL }}"
# output e.g. : master feat-new-feature v1-0-0 product-1-0-0-rc-2 new-awesome-product
echo "Short SHA variables"
echo " - ${{ env.GITHUB_SHA_SHORT }}"
# output e.g. : ffac537e
Solution 6:[6]
How to get the current branch within Github Actions?
Assuming ${{ github.ref }}
is something like refs/heads/mybranch
, you can extract the branch name using the following method:
steps:
- name: Prints the current branch name
run: echo "${GITHUB_BRANCH##*/}"
env:
GITHUB_BRANCH: ${{ github.ref }}
If your branch includes slashes (such as feature/foo
), use the following syntax:
steps:
- name: Prints the current branch name
run: echo "${GITHUB_REF#refs/heads/}"
Credits: @rmunn comment
Or use the method from the accepted answer, here is much shorter version (lint friendly):
steps:
- name: Get the current branch name
shell: bash
run: echo "::set-output name=branch::${GITHUB_REF#refs/heads/}"
id: myref
Then refer in other steps as ${{ steps.myref.outputs.branch }}
.
Notes:
- Above methods works only for Unix-based images (Linux and macOS).
- For docs, read: Context and expression syntax for GitHub Actions.
Solution 7:[7]
The GitHub Action FranzDiebold/github-env-vars-action exposes several useful environment variables, such as current branch name and their slug values. I made this action exactly for this use case.
Usage
steps:
- uses: FranzDiebold/[email protected]
- name: Print environment variables
run: |
echo "GITHUB_REPOSITORY_SLUG=$GITHUB_REPOSITORY_SLUG"
echo "GITHUB_REPOSITORY_OWNER=$GITHUB_REPOSITORY_OWNER"
echo "GITHUB_REPOSITORY_OWNER_SLUG=$GITHUB_REPOSITORY_OWNER_SLUG"
echo "GITHUB_REPOSITORY_NAME=$GITHUB_REPOSITORY_NAME"
echo "GITHUB_REPOSITORY_NAME_SLUG=$GITHUB_REPOSITORY_NAME_SLUG"
echo "GITHUB_REF_SLUG=$GITHUB_REF_SLUG"
echo "GITHUB_REF_NAME=$GITHUB_REF_NAME"
echo "GITHUB_REF_NAME_SLUG=$GITHUB_REF_NAME_SLUG"
echo "GITHUB_SHA_SHORT=$GITHUB_SHA_SHORT"
A demo for all Operating systems (Linux, macOS and Windows) is also available in the demo workflows file of the repository!
Solution 8:[8]
Just use:
env:
BRANCH_NAME: ${{ github.head_ref || github.ref_name }}
The trick is that github.head_ref
is only set when the workflow was triggered by a pull_request
and it contains the value of the source branch of the PR. github.ref_name
will than only be used if the workflow was not triggered by a pull_request
and it also just contains the branch name.
Solution 9:[9]
To set it as an environment variable, I use this syntax:
- name: Extract branch name
shell: bash
run: echo "::set-env name=BRANCH_NAME::$(echo ${GITHUB_REF#refs/heads/} | sed 's/\//_/g')"
- name: Test
run: echo "${BRANCH_NAME}"
I found this syntax here: Github actions - starter worflows#How to define env variable? #68
Rmq: the sed 's/\//_/g'
is to replace /
by _
in the branch name
Solution 10:[10]
Update
GitHub now supports the GITHUB_REF_NAME
, which stands for: The branch or tag name that triggered the workflow run
.
GitHub docs on this https://docs.github.com/en/actions/learn-github-actions/environment-variables
Solution 11:[11]
I just made a simple test within GitHub Actions using a bash script:
#!/bin/bash
echo Reserved for REPO_NAME=${GITHUB_REPOSITORY##*/}
echo GITHUB_REF=${GITHUB_REF}
echo EXTRACT_GITHUB_REF=${GITHUB_REF##*/}
echo EXTRACT_GITHUB_REF_HEADS=$(echo ${GITHUB_REF#refs/heads/})
cd $REPO_NAME
git checkout ${GITHUB_REF##*/}
git checkout $(echo ${GITHUB_REF#refs/heads/})
Here is screenshot of the output:
So both ${GITHUB_REF##*/}
and $(echo ${GITHUB_REF#refs/heads/})
are correct
Solution 12:[12]
Heres a complete workflow that works for both push
and pull_request
events
name: whichBranch
on: [pull_request, push]
jobs:
which_branch:
runs-on: ubuntu-latest
steps:
- name: Extract branch name on push
if: github.event_name != 'pull_request'
shell: bash
run: echo "::set-env name=BRANCH_NAME::$(echo ${GITHUB_REF#refs/heads/})"
id: extract_branch
- name: Extract branch name on pull request
if: github.event_name == 'pull_request'
run: echo "::set-env name=BRANCH_NAME::$(echo ${GITHUB_HEAD_REF})"
- name: Print branch name
run: echo 'The branch name is' $BRANCH_NAME
Solution 13:[13]
${{ github.ref_name }}
Seems to work fine for for pushes at least.
Solution 14:[14]
For those just finding this thread, you can now use GITHUB_REF_NAME
e.g. ${{ github.ref_name }}
. https://docs.github.com/en/actions/learn-github-actions/environment-variables#default-environment-variables
So if your triggered action workflow branch is main
this variable will be set to main
. This is useful if you have multiple repos with release
and main
branches, for instance.
Solution 15:[15]
If you're using V2 of actions/checkout
then you can always just run git branch --show-current
to just get the name of the branch currently checked out.
Solution 16:[16]
Now ${{github.ref}}
is the correct way to get branch name.
Please remember ${{github.ref}}
has refs/heads/..
prefix
Solution 17:[17]
Solution to deal with both pull_request
and push
events. Implements the workaround to save obtained branch name for further steps, since set-env
is deprecated.
Doesn't require third-party actions.
name: CI
on: [ pull_request, push ]
jobs:
build:
runs-on: ubuntu-latest
steps:
- name: "Get branch name and save to env"
env:
IS_PR: ${{ github.EVENT_NAME == 'pull_request' }}
run: |
if ${IS_PR}; then
BRANCH_NAME="${GITHUB_HEAD_REF}"
else
BRANCH_NAME="${GITHUB_REF##*/}"
fi
echo "BRANCH_NAME=${BRANCH_NAME}" >> $GITHUB_ENV
- name: "Another step uses branch name"
run: echo "Branch name is ${{ env.BRANCH_NAME }}"
Solution 18:[18]
To also deal with the pull_request
event (in which case the $GITHUB_REF
contains something not useful like refs/pull/519/merge
) you can use this one liner:
- name: Set branch name
run: echo "::set-output name=branch_name::$(echo ${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}})"
Solution 19:[19]
Use branch name on GitHub actions
Convenience action for using current branch name. Usage
name: build
on: push
jobs:
build:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v1
- run: npm ci
- uses: nelonoel/branch-name@v1
# Use branch name for whatever purpose
- run: echo ${BRANCH_NAME}
Solution 20:[20]
For people using Windows image to run actions, a few key points to know about:
- It's incorrect to assume that GitHub actions use CMD shell. They use PowerShell by default.
- You can specify the shell to use the following way:
- run: |
...
shell: cmd
- You can use the value 'bash' to execute a command in the context of a bash shell.
So, all in all, you don't need to waste potentially hours trying to figure out how to do things in dilapidated cmd way (like I did).
And for the simple purpose of getting the name of the current branch, you can either use the popular solutions while setting the shell to 'bash', or use for example the following simple way to set a variable in the default PowerShell shell:
$branchName = $Env:GITHUB_REF -replace "refs/heads/", ""
Solution 21:[21]
I made an action that gets the branch name regardless of pull_request trigger or not. https://github.com/EthanSK/git-branch-name-action
Solution 22:[22]
Just repeating here for better visibility what others have written as simple comments in previous replies:
https://docs.github.com/en/actions/learn-github-actions/environment-variables
The branch name for pull requests only is exposed in this environment variable:
GITHUB_HEAD_REF Only set for pull request events. The name of the head branch.
In GitHub actions, the corresponding context key is:
github.head_ref
Solution 23:[23]
if: github.ref == 'refs/heads/integration' && github.event_name == 'push'
You can use the above command and replace whatever branch or event you want to run for.
Solution 24:[24]
Running on Windows?. Windows default command is a PowerShell terminal.
- name: SET CURRENT_BRANCH
run: |
$branchName = "${{github.ref}}".Split("/")["${{github.ref}}".Split("/").Length -1]
echo "::set-env name=CURRENT_BRANCH::$(echo $branchName)"
Solution 25:[25]
Here's a snippet which set's an environment variable based on $GITHUB_REF
, which defaults to dev
if not present.
Adjust the sed command as per your requirements.
export GIT_BRANCH=$(echo ${GITHUB_REF:-dev} | sed s/.*\\///g)
Solution 26:[26]
Normally, I always have a script written in either nodejs
or python
, which gets invoked from the workflow.yaml
. The script normally takes care of works like getting proper branch reference.
I have a function like below, in a prepare-deployment.js
script-
const VALID_REF_PREFIX = 'refs/heads/';
...
function getBranchRef(isProd = false) {
let branchRef = 'origin/master';
if (isProd) {
return branchRef;
}
/**
* When the workflow is invoked from manual flow, the branch name
* is in GITHUB_REF, otherwise, we have to look into GITHUB_BASE_REF
*/
if (GITHUB_REF.startsWith(VALID_REF_PREFIX)) {
// coming from a manual workflow trigger
branchName = `origin/${GITHUB_REF.replace(VALID_REF_PREFIX, '')}`;
} else {
// coming from a PR
branchRef = `origin/${GITHUB_HEAD_REF}`;
}
return branchRef;
}
This takes care of the following scenarios-
- I want to deploy changes from a PR to my dev env
- I want to deploy changes from any branch I want into my dev env, via a manual trigger
- I want to deploy changes from master into my prod env
Solution 27:[27]
There's a very simple git command to get the current branch:
git rev-parse --abbrev-ref HEAD
To get the output in an env file variable simply put:
- name: Set CURRENT_BRANCH run: echo "CURRENT_BRANCH=$(git rev-parse --abbrev-ref HEAD)" >> $GITHUB_ENV
To get the output from the env variable:
- name: Get CURRENT_BRANCH run: echo ${{ env.CURRENT_BRANCH}}
Source: https://www.techiedelight.com/determine-current-branch-name-git/
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow