Grab parameters from url and drop them to powershell variables - powershell

Question

i have a powershell listener running on my windows-box. Code from Powershell-Gallery: https://www.powershellgallery.com/packages/HttpListener/1.0.2
The "Client" calls the listener with the following example url:
With Powershell i do:
invoke-webrequest -Uri "http://127.0.0.1:8888/Test?id='1234'&param2='##$$'&param3='This is a test!'"
I have no idea, how to drop the parameters from the url to variables with the same name in powershell. I need to bring the parameters to powershellvariables to simply echo them. this is my last missing part. The parameters are separated with & and parameternames are case-sensitive.
To be more detailed, the id from the url should be in a powershell-variable named $id with the value 1234. The Variables can contain spaces, special characters, numbers, alphas. They are case sensitive. The parametervalue could be "My Name is "Anna"! My Pets Name is 'Bello'. " with all the "dirty" Characters like '%$"!{[().
Can someone point me to the right way how to get this solved?

Answer 1

In a valid url, the $ characters should have been escaped to %24
The other 'dirty' character % in Url escaped form is %25
This means the example url is invalid and should be:
$url = "http://127.0.0.1:8888/Test?id='1234'&param2='##%24%24'&param3='This is a test!'"
Then the following does work
$url = "http://127.0.0.1:8888/Test?id='1234'&param2='##%24%24'&param3='This is a test!'"
if ($url -is [uri]) {
$url = $url.ToString()
}
# test if the url has a query string
if ($url.IndexOf('?') -ge 0) {
# get the part of the url after the question mark to get the query string
$query = ($url -split '\?')[1]
# or use: $query = $url.Substring($url.IndexOf('?') + 1)
# remove possible fragment part of the query string
$query = $query.Split('#')[0]
# detect variable names and their values in the query string
foreach ($q in ($query -split '&')) {
$kv = $($q + '=') -split '='
$varName = [uri]::UnescapeDataString($kv[0]).Trim()
$varValue = [uri]::UnescapeDataString($kv[1])
New-Variable -Name $varname -Value $varValue -Force
}
}
else {
Write-Warning "No query string found as part of the given URL"
}
Prove it by writing the newly created variables to the console
Write-Host "`$id = $id"
Write-Host "`$param2 = $param2"
Write-Host "`$param3 = $param3"
which in this example would print
$id = '1234'
$param2 = '##$$'
$param3 = 'This is a test!'
However, I personally would not like to create variables like this, because of the risk of overwriting already existing ones.
I think it would be better to store them in a hash like this:
# detect variable names and their values in the query string
# and store them in a Hashtable
$queryHash = #{}
foreach ($q in ($query -split '&')) {
$kv = $($q + '=') -split '='
$name = [uri]::UnescapeDataString($kv[0]).Trim()
$queryHash[$name] = [uri]::UnescapeDataString($kv[1])
}
$queryHash
which outputs
Name Value
---- -----
id '1234'
param2 '##$$'
param3 'This is a test!'