Problem to connect to TFS with user/password - rest

Question

When I try to connect to tfs the function Get-Data failed with 401 error although the function Get-DataWithCred succeed with the same argument.
And don't understand the difference with this two ?
function Get-Data([string]$username, [string]$password, [string]$url)
{
# Step 1. Create a username:password pair
$credPair = "$($username):$($password)"
# Step 2. Encode the pair to Base64 string
$encodedCredentials = [System.Convert]::ToBase64String([System.Text.Encoding]::ASCII.GetBytes($credPair))
# Step 3. Form the header and add the Authorization attribute to it
$headers = #{ Authorization = "Basic $encodedCredentials" }
# Step 4. Make the GET request
$responseData = Invoke-WebRequest -Uri $url -Method Get -Headers $headers
return $responseData
}
function Get-DataWithCred([string]$username, [string]$password, [string]$url)
{
$p = ConvertTo-SecureString -String $password -AsPlainText -Force
$Cred = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $username, $p
$responseData = Invoke-WebRequest -Uri $url -Method Get -Credential $Cred
return $responseData
}
The purpose is too connect through tfs with python script who failed the same way that the function Get-Data when I use the requests library.
>>> r = requests.get('https://tfs-url.com', auth=('user', 'pass'))
>>> r.status_code
401

Answer 1

Looks like there is a problem with $encodedCredentials.
Take a look at Choosing the right authentication mechanism
For my script who connect to TFS i use the following code :
$strUser = 'domain\userID'
$password = "YOURPASSWORD"
$strPass = ConvertTo-SecureString -String $password -AsPlainText -Force
$cred= New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList ($strUser, $strPass)
And than connect to the TFS as you did :
$responseData = Invoke-WebRequest -Uri $url -Method Get -Credential $cred
Or, If you would like to connect to the TFS with the user who runs the script you can use
-UseDefaultCredentials
code snippet :
$responseData = Invoke-WebRequest -Uri $url -Method Get -UseDefaultCredentials

Answer 2

You need to use a microsoft way to pass your credential : the ntlm protocol.
This protocol are not supported by default by requests but a library requests_ntlm extend requests by adding support to ntlm.
A simple example:
import os
import requests
from requests_ntlm import HttpNtlmAuth
def main():
user = "user"
password = "password"
session = requests.Session()
session.auth = HttpNtlmAuth(user, password)
url = "https://tfs-url.com"
response = session.get(url)
print(response)
if __name__ == "__main__":
main()