polaris.ps1

Import-module Polaris -force
# Using a script block

New-PolarisPostRoute -Path "/Pcc" -ScriptBlock {
   $json = $Request.Body
   $comp = $json.computerName
   $FileName = $Json.FileName
   $return = $comp + $FileName
   $response.Send($return)
} -Force

New-PolarisGetRoute -Path '/get' -Scriptblock {
    $Response.send('plop')
}

# Using a script path
Start-Polaris -UseJsonBodyParserMiddleware -Verbose

<#
Code call for testing:
$Data = @{
    FileName = 'plop.ps1'
    ComputerName = $Env:computerNAme
    PackageName = 'plop'
    RunTime = '1.4.5'
    
}
$JsonBody = $Data | ConvertTo-Json
#both ways here freen
Invoke-RestMethod -Method post -Uri http://localhost:8080/Pcc -Body $Jsonbody -ContentType 'application/json' -verbose

Okay - Try this!

New-PolarisPostRoute -Path "/Pcc" -ScriptBlock {
    $Response.SetContentType('application/json')
    $Request.Body = $Request.BodyString | ConvertFrom-Json
    $Response.send(($Request.Body | ConvertTo-Json))
}

Now, your client request

$Data = @{
    FileName = 'plop.ps1'
    ComputerName = $Env:computerNAme
    PackageName = 'plop'
    RunTime = '1.4.5'
    
} | ConvertTo-Json

Invoke-RestMethod -Method post -Uri http://localhost:8080/Pcc -Body $Data