Github Action saving output, but output is not available on another step

[GammaGames]

I've been working on adding optional stdout capturing to a community action: appleboy/ssh-action#287. I updated the script to capture the output with a heredoc:

  echo 'stdout<<EOF' >> $GITHUB_OUTPUT # use heredoc for multiline output
  sh -c "${TARGET} $*" | tee -a $GITHUB_OUTPUT # run the command
  echo 'EOF' >> $GITHUB_OUTPUT

The workflow uses the local action and attempts to print the output:

      - id: stdout
        name: ssh command with stdout
        uses: ./
        with:
          host: ${{ env.REMOTE_HOST }}
          username: linuxserver.io
          password: password
          port: 2222
          capture_stdout: 'true'
          script: |
            #!/usr/bin/env bash
            set -e
            whoami

      - name: check stdout
        run: |
          echo "stdout: ${{ steps.stdout.outputs.stdout }}"

It ran fine with nektos act, but for some reason it wasn't showing on github. I enabled debug mode and ran it again to confirm that it is saving the output:

[ssh command with stdout]
##[debug]/usr/bin/bash --noprofile --norc -e -o pipefail /home/runner/work/_temp/edf90d65-d99c-4efa-93b2-8068d6559cf3.sh
Will download drone-ssh-1.8.0-linux-amd64 from https://github.com/appleboy/drone-ssh/releases/download/v1.8.0
======= CLI Version =======
Drone SSH version 1.8.0
===========================
linuxserver.io
===============================================
✅ Successfully executed commands to all hosts.
===============================================
##[debug]Set output stdout = linuxserver.io
##[debug]===============================================
##[debug]✅ Successfully executed commands to all hosts.
##[debug]===============================================
##[debug]Finished: run
##[debug]Finishing: ssh command with stdout

---
[check stdout]
##[debug]Evaluating condition for step: 'check stdout'
##[debug]Evaluating: success()
##[debug]Evaluating success:
##[debug]=> true
##[debug]Result: true
##[debug]Starting: check stdout
##[debug]Loading inputs
##[debug]Evaluating: format('echo "stdout: {0}"
##[debug]', steps.stdout.outputs.stdout)
##[debug]Evaluating format:
##[debug]..Evaluating String:
##[debug]..=> 'echo "stdout: {0}"
##[debug]'
##[debug]..Evaluating Index:
##[debug]....Evaluating Index:
##[debug]......Evaluating Index:
##[debug]........Evaluating steps:
##[debug]........=> Object
##[debug]........Evaluating String:
##[debug]........=> 'stdout'
##[debug]......=> Object
##[debug]......Evaluating String:
##[debug]......=> 'outputs'
##[debug]....=> Object
##[debug]....Evaluating String:
##[debug]....=> 'stdout'
##[debug]..=> null
##[debug]=> 'echo "stdout: "
##[debug]'
##[debug]Result: 'echo "stdout: "
##[debug]'
##[debug]Loading env
Run echo "stdout: "
##[debug]/usr/bin/bash -e /home/runner/work/_temp/6fe0f054-2d28-4b9e-a641-fe2e191b2cba.sh
stdout: 
##[debug]Finishing: check stdout

You can see that it is being stored but the next step is evaluating the variable to null. Am I doing something wrong here?

[GammaGames]

The solution was that I had to give the action an id and map the output: appleboy/ssh-action@40c4aad