How to handle errors from CLI command in PowerShell

[MartinM85]

I'm trying to call a CLI command from the PowerShell script like

try {
    $users = m365 entra user list --type Member --properties 'id,userPrincipalName' --output json | ConvertFrom-Json
}
catch {
    Write-Host "Errors: $($_.Exception.Message) "
}

But due to missing permissions it fails and the output is only error message

Error: Insufficient privileges to complete the operation.

Is there any way to check if the command has failed?

[milanholemans]

If I'm not mistaken, PowerShell struggles to handle stderr output. A function like this can help:

function Invoke-CliM365Command {
  param (
    [Parameter(Mandatory = $true, ValueFromRemainingArguments = $true)]
    [string]$command
  )

  $output = Invoke-Expression "$command 2>&1"
  if ($LASTEXITCODE -ne 0) {
    throw $output
  }
  if ($output) {
    return $output | ConvertFrom-Json
  }
}

Then you can use it like:

$sites = Invoke-CliM365Command "m365 spo site list"

@martinlingstuyl, correct me if I'm wrong or forgot something 🙂

[martinlingstuyl]

Couple of notes on this. 2>&1 redirects the stderr stream to stdout. That's neat. You could also use the CLI config for this:

m365 cli config set --key errorOutput --value stdout

Furthermore, I'm using the following helper function in my PowerShell Profile:

function Invoke-CLICommand {
  [cmdletbinding()]
  param(
    [parameter(Mandatory = $true, ValueFromPipeline = $true)] $input
  )

  $output = $input

  if ($null -eq $output) {
    return $null
  }

  $parsedOutput = $output | ConvertFrom-Json

  if ($parsedOutput -isnot [Array] -and $null -ne $parsedOutput.error) {
    throw $parsedOutput.error
  }

  return $parsedOutput
}

This script assumes the following CLI config values: errorOutput set to stdout and printErrorsAsPlainText is set to false.

Which I can pipe stuff into:

$sites = m365 spo site list -o json | Invoke-CLICommand

[martinlingstuyl]

But I like @milanholemans script as well, because it does not make an assumption about the CLI configs being set correctly.

[Adam-it]

same as @martinlingstuyl I do the following in my scripts

m365 cli config set --key output --value json
m365 cli config set --key errorOutput --value stdout
m365 cli config set --key showHelpOnFailure --value false
m365 cli config set --key printErrorsAsPlainText --value false

function Get-CLIValue {
    [cmdletbinding()]
    param(
        [parameter(Mandatory = $true, ValueFromPipeline = $true)]
        $input
    )
    $output = $input | ConvertFrom-Json
    if ($null -ne $output.error) {
        throw $output.error
    }
    return $output
}

try {
    # some script here like 
    m365 spo list list --webUrl "random" | Get-CLIValue 
}
catch {
    Write-Host "Errors: $($_.Exception.Message) "
}

[Adam-it]

in this case we get the expected behavior as I do not have site with ulr random on my tenant 😉

[Adam-it]

That being said we are still investigating how CLI for M365 could better and more natively integrate with PowerShell. It is not that easy as CLI may be used in any shell so we need to consider this as well

[MartinM85]

When you type the wrong command name, the error is not JSON, so it's better to have a try-catch around ConvertFrom-Json

function Get-CLIValue {
    [cmdletbinding()]
    param(
        [parameter(Mandatory = $true, ValueFromPipeline = $true)]
        $input
    )

    $rawOutput = $input
    try {
      $output = $rawOutput | ConvertFrom-Json
      if ($null -ne $output.error) {
        throw $output.error
      }
      return $output
    }
    catch {
      throw $rawOutput
    }
  }

[Adam-it]

didn't anticipate this scenario 🙂
good call 👍

[MartinM85]

@milanholemans @martinlingstuyl @Adam-it
Thanks. All helpers work great. I like them all.

I will try them out to see what suits me best.