我相信GITHUB_REF是唯一包含分支名称的环境变量。

你可以从字符串的其余部分提取分支名称，如下所示:

${GITHUB_REF##*/}

例子:

$ GITHUB_REF=refs/heads/feature-branch-1
$ echo ${GITHUB_REF##*/}
feature-branch-1

更新:添加了一个完整的工作流示例。

工作流

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##*/} .

来源:https://github.com/tedmiston/x/blob/master/.github/workflows/workflow.yml

示例输出-主分支

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

日志:https://github.com/tedmiston/x/commit/cdcc58a908e41d3d90c39ab3bf6fef1ad2c4238a/checks一步:16

示例输出-非主分支

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

日志:https://github.com/tedmiston/x/commit/4e8d31259f861aaa2c30375756fc081c3659bddf/checks一步:16

有关参数展开语法的更多信息，请参阅这个答案。

作为参考，GitHub Actions的虚拟环境页面列出了执行环境中可用的所有环境变量。

你可以使用https://github.com/rlespinasse/github-slug-action

# Just add this  => 
- name: Inject slug/short variables
  uses: rlespinasse/github-slug-action@v3.x



# 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

同时处理pull_request和push事件的解决方案。由于set-env已弃用，因此实现了保存获得的分支名称以供后续步骤使用的变通方法。 不需要第三方操作。

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 }}"

GitHub动作中的运行时变量

GitHub Action FranzDiebold/ GitHub -env- vals - Action公开了几个有用的环境变量，例如当前分支名称及其slug值。我为这个用例做了这个操作。

使用

steps:
  - uses: FranzDiebold/github-env-vars-action@v1.2.0
  - 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"

所有操作系统(Linux, macOS和Windows)的演示也可以在存储库的演示工作流文件!

在这里重复一下，以便更好地看到其他人在之前的回复中作为简单注释写的内容:

https://docs.github.com/en/actions/learn-github-actions/environment-variables

只在这个环境变量中暴露了pull请求的分支名称:

仅为拉请求事件设置。总行的名称。

在GitHub动作中，对应的上下文键是:

github.head_ref

if: github.ref == 'refs/heads/integration' && github.event_name == 'push' 

您可以使用上面的命令替换您想要运行的任何分支或事件。