Powershell Switch Parameters No Values Required

usecase

The aim of this tutorial🔍 is the lesson needed for starting to use powershell’s functions with just -parameter without the provision of any value

• 1. steps/?
• 2. example: query hashicorp consul

1. steps/?

• this features is called switch parameters
• handled in about_Functions_Advanced_Parameters - PowerShell @ Microsoft Docs
• the control flow is handled elegantly with truthy test against the value

if($switchname) {activated}

• you need to set a proper type [switch] before the argument
• this works also in simple inline functions without the lenghty param block

2. example: query hashicorp consul

• this is my local script I am using during operations to lookup a given value from within HashiCorps Consul database
• there are other things I am implementing: a short command-help, and argument typing
• the prereq to using this is
  • Consul installed
  • Consul authenticated

>>> query-consul com_acme md5 -detailed

function query-consul ([string]$customer, [string]$queryString, [int]$context, [switch]$detailed) {
    $consulURL = "https://consul.foo.net/ui/eu-central-1/kv/customer/$customer"
    
    elseif ($detailed) {
        consul kv get -recurse -detailed customer/$customer |
            Select-String $queryString -Context 1, $context
    }
    else {
        consul kv get -recurse customer/$customer |
            Select-String $queryString -Context 1, $context
    }
<#
.SYNOPSIS
    - Function querying Hashicorp Consul'KV for the a string in question
.DESCRIPTION
    - Provide an empty string to query all folders
    - Run with -detailed flag to get richer outout
    - You can provide -context [int] to get richer output
#>
}