[SOLVED] Unable to Run bash script of remote Linux host using powershell in GitHub actions

Issue

I have a bash script check_disk_space.sh to check and error exit if disk space for a given mount on a Linux Centos 7 host is less than the threshold(30GB for example).

check_disk_space.sh has 3 input parameters

1. ${{ inputs.mount_points }} which could be a comma-separated mount point like /tmp,/etc
2. ${{ inputs.min_free_space }} which is the threshold below which free disk space should error and exit.
3. "$eachhost" which is each host obtained from the comma-separated list hosts where the script(check_disk_space.sh) runs and checks for free space.

This is running fine using Github Linux runners as below.

  steps:

    - name: Check Disk Space on Remote Hosts
      shell: bash

      run: |

        cd "${{ github.workspace }}/DevOps/scripts"

        IFS=',' read -ra remhosts <<< "${{ inputs.remote_hosts }}"

        for eachhost in "${remhosts[@]}"; do
          ssh -q -t user@"$eachhost" "bash -s" -- < ./check_disk_space.sh "${{ inputs.mount_points }}" "${{ inputs.min_free_space }}" "$eachhost"
        done

This works fine however, I now wish to use a Windows runner due to policy constraints.

I tried the below by hard coding the values, but I get an error in doing so.

name: Attempt2 Check Disk Space on Remote Hosts

on:
  push:
    branches:
      - main

jobs:
  check_disk_space:
    runs-on: windows-latest

    steps:
      - name: Checkout code
        uses: actions/checkout@v2

      - name: Check Disk Space on Remote Hosts
        shell: powershell

        run: |
          $remoteHosts = "80.240.24.193,80.240.24.194".Split(",")
          $mountPoints = "/tmp"
          $minFreeSpace = "5"
          $user = "root"

          cd $env:GITHUB_WORKSPACE

          $scriptcode = Get-Content -Raw -Path ./check_disk_space.sh

          foreach ($eachhost in $remoteHosts) {
            $sshCommand = "ssh -q -t $user@$eachhost `"bash -s`" --"

            $command = @"
            $scriptcode
           ./check_disk_space.sh "$mountPoints" "$minFreeSpace" "$eachhost"
           "@

            $finalCommand = ($sshCommand + " `"$(echo $command)`"").Trim()
            Write-Output $finalCommand
            Invoke-Expression $finalCommand
          }

Error:

Run $remoteHosts = "80.240.24.193,80.240.24.194".Split(",")
At D:\a\_temp\06b226b4-60d8-40ca-82d2-f8f76669f636.ps1:17 char:2
+  "@
+  ~~
White space is not allowed before the string terminator.
At D:\a\_temp\06b226b4-60d8-40ca-82d2-f8f76669f636.ps1:11 char:37
+ foreach ($eachhost in $remoteHosts) {
+                                     ~
Missing closing '}' in statement block or type definition.
    + CategoryInfo          : ParserError: (:) [], ParseException
    + FullyQualifiedErrorId : WhitespaceBeforeHereStringFooter

Thus, my attempt to run check_disk_space.sh using PowerShell on a remote linux host fails for which I got no clue why.

Sample run with error here: https://github.com/knowyrtech/invokebashfrompowershell/actions/runs/5894294098/job/15987641430

I tried a different approach which was resolved by the accepted answer but unable to use it to execute check_disk_space.sh script of remote Linux there too: Unable to use powershell's sshArgs to invoke a simple ssh command on remote linux host

Can you please suggest?

Solution

You are using the $host variable in PowerShell and you are probably not aware of that it is an automatic variable in PowerShell. Replace it by whatever you really want.

Concerning your error message: You are passing two strings to Invoke-Expression, but this cmdlet expects only one string. Either adjust your quoting or use another approach like direct invocation or Start-Process.

Answered By - stackprotector

Answer Checked By - Senaida (WPSolving Volunteer)