Git actions branch

Question

So I have two secrets: DEV_SERVER_IP and MASTER_SERVER_IP. in main.yml I need something like this

 run: echo "::set-env name=BRANCH_NAME::$(echo ${GITHUB_REF#refs/heads/} | sed 's/\//_/g')"   

     run: ssh-keyscan -H ${{ secrets.BRANCH_NAME_SERVER_IP }} >> ~/.ssh/known_hosts

but am getting error

  env:
    BRANCH_NAME: dev
Error: Input required and not supplied: key

I need here something like this ssh-keyscan -H ${{ secrets.${BRANCH_NAME}_SERVER_IP }}

how can I fix this?

Answer 1

You're trying to use shell style logic inside a Github context expansion (${{ ... }}) which won't work. Just move all your logic into your shell script instead:

name: Example

on:
  push:

jobs:
  example:
    runs-on: ubuntu-latest
    steps:
      - name: get target ip
        env:
          DEV_SERVER_IP: ${{ secrets.DEV_SERVER_IP }}
          MAIN_SERVER_IP: ${{ secrets.MAIN_SERVER_IP }}
        run: |
          branch_name=$(sed 's|/|_|g' <<< ${GITHUB_REF#refs/heads/})
          target="${branch_name^^}_SERVER_IP"
          mkdir -p ~/.ssh
          ssh-keyscan -H ${!target} >> ~/.ssh/known_hosts
          cat ~/.ssh/known_hosts

In the above workflow, the expression ${branch_name^^} is a bash expression that returns the value of $branch_name in uppercase, and ${!target} is a bash expression that returns the value of the variable who name is stored in $target.

Note that I'm not using your "set the BRANCH_NAME environment variable" task because the ::set-env command is disabled by default for security reasons.