# init
$who=whoami
$computer=hostname
$server="my-server.domain.com"

# before the main command, let's call the API
Invoke-WebRequest ("http://{2}:5000/my_command/start/{0}/{1}" -f ($who -replace "\\", "@"), $computer, $server) -Method POST

# main command
my_action

# after the main command, let's call the API
Invoke-WebRequest ("http://{2}:5000/my_command/end/{0}/{1}" -f ($who -replace "\\", "@"), $computer, $server) -Method POST