A PowerShell Script to set credentials as environment variables. Password is not stored as plain text.

SetSharePointCredentials.ps1

# Description
# This Script sets Sharepoint Credentials as environment variables so
# you are not prompted on your script every time
#
# Usage 
# 
# PS> SetSharepointCredentials
# 
# It will prompt the user to type site url, username, password. If it is successful 
#
# It will set the env variables SHAREPOINT_USER, SHAREPOINT_PASSWORD and SHAREPOINT_URL
# 
# In other scripts it can be used in the following way:
#  $URL = "http://dev.sharepoint.site.url/"
#
# # If environment variable with sharepoint URL is set, use it
#  if (Test-Path env:SHAREPOINT_URL) {
#      $URL = $env:SHAREPOINT_URL 
#  }
#
#  # If sharepoint credentials are set on environment variables - use them
#  if ((Test-Path env:SHAREPOINT_USER) -And (Test-Path env:SHAREPOINT_PASSWORD)) {
#      # Convert from Encripted string to a SercurePassword Object
#      $SecurePassword = ConvertTo-SecureString -String $env:SHAREPOINT_PASSWORD -Key (1..16)
#      $Credential = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $env:SHAREPOINT_USER, $SecurePassword
#  } else {
#      # Ask for credentials
#      $Credential = Get-Credential
#   }
#   
#  Connect-PnPOnline -Url $URL -Credentials $Credential
#  Write-Host "Connected to SharePoint site." -ForegroundColor Green
#
#

# --- INSTALl ----
# This should be run as Admin ( Start-Process powershell -Verb runAs )
if (-not (Get-Module -ListAvailable -Name SharePointPnPPowerShellOnline)) {
   Install-Module SharePointPnPPowerShellOnline
}
# ----
Import-Module SharePointPnPPowerShellOnline

#
# Default Sharepoint site
#
$DefaultSharepointUrl = "https://xxx.sharepoint.com/sites/xxx"
#
# Default Sharepoint User
#
$DefaultSharepointUser = "xxx@xxx.onmicrosoft.com"

# By default we load whatever is on the env variable.
if (Test-Path env:SHAREPOINT_URL) {
  $DefaultSharepointUrl = $env:SHAREPOINT_URL
}
if (Test-Path env:SHAREPOINT_USER) {
  $DefaultSharepointUser = $env:SHAREPOINT_USER
}

# Prompt user to set its credentials
$Url =  Read-Host "Sharepoint site URL (default: $DefaultSharepointUrl)"
# If user leaves the empty string => use the default
if ($Url -eq "") {
  $Url = $DefaultSharepointUrl
}
$User = Read-Host "Username (default: $DefaultSharepointUser)"
if ($User -eq "") {
  $User = $DefaultSharepointUser
}

$SecurePassword = Read-Host -assecurestring "Password for ($User)"


# Test the connection
Try {
  $Credential = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $User, $SecurePassword
  Connect-PnPOnline -Url $Url -Credentials $Credential
  # If there is not problem with credentials save as env vars
  $env:SHAREPOINT_URL = $Url
  $env:SHAREPOINT_USER = $User
  $EncriptedPassword = ConvertFrom-SecureString -SecureString $SecurePassword -Key (1..16)
  $env:SHAREPOINT_PASSWORD = $EncriptedPassword
  Write-Host "ENV variables of credentials Updated"
} Catch {
  Write-Host "ERROR Logging in. Credentials were not updated"
}