(PowerShell) PayPal -- Get an OAuth 2.0 Access Token

Demonstrates how to send a request to get a PayPal OAuth2 access token. Sends an HTTP request equivalent to the following:

curl https://api.sandbox.paypal.com/v1/oauth2/token \
  -H "Accept: application/json" \
  -H "Accept-Language: en_US" \
  -u "Client-Id:Secret" \
  -d "grant_type=client_credentials"

Chilkat .NET Downloads Chilkat .NET Assemblies

Add-Type -Path "C:\chilkat\ChilkatDotNet47-9.5.0-x64\ChilkatDotNet47.dll"

# Note: Requires Chilkat v9.5.0.64 or greater.

# This requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

$rest = New-Object Chilkat.Rest

# Make the initial connection.
# A single REST object, once connected, can be used for many PayPal REST API calls.
# The auto-reconnect indicates that if the already-established HTTPS connection is closed,
# then it will be automatically re-established as needed.
$bAutoReconnect = $true
$success = $rest.Connect("api.sandbox.paypal.com",443,$true,$bAutoReconnect)
if ($success -ne $true) {
    $($rest.LastErrorText)
    exit
}

# Duplicate this request:

# 	curl https://api.sandbox.paypal.com/v1/oauth2/token \
# 	  -H "Accept: application/json" \
# 	  -H "Accept-Language: en_US" \
# 	  -u "Client-Id:Secret" \
# 	  -d "grant_type=client_credentials"

$rest.AddHeader("Accept","application/json")
$rest.AddHeader("Accept-Language","en_US")

# For additional help on where to find  your client ID and API secret, see PayPal Client_ID and API_Secret
$rest.SetAuthBasic("PAYPAL_REST_API_CLIENT_ID","PAYPAL_REST_API_SECRET")

$rest.AddQueryParam("grant_type","client_credentials")

$responseStr = $rest.FullRequestFormUrlEncoded("POST","/v1/oauth2/token")
if ($rest.LastMethodSuccess -ne $true) {
    $($rest.LastErrorText)
    exit
}

$($rest.LastRequestHeader)

# A sample response:

# 	{
# 	  "scope": "https://api.paypal.com/v1/payments/.* https://api.paypal.com/v1/vault/credit-card https://api.paypal.com/v1/vault/credit-card/.*",
# 	  "access_token": "EEwJ6tF9x5WCIZDYzyZGaz6Khbw7raYRIBV_WxVvgmsG",
# 	  "token_type": "Bearer",
# 	  "app_id": "APP-6XR95014BA15863X",
# 	  "expires_in": 28800
# 	}

$json = New-Object Chilkat.JsonObject
$json.Load($responseStr)
$json.EmitCompact = $false

# Check the response status code.  A 200 indicates success..
if ($rest.ResponseStatusCode -ne 200) {
    $($json.Emit())
    $("Failed.")
    exit
}

# Given that the access token expires in approx 8 hours,
# let's record the date/time this token was created.
# This will allow us to know beforehand if the token
# is expired (and we can then fetch a new token).
$dateTime = New-Object Chilkat.CkDateTime
$bLocalTime = $false
$dtNow = $dateTime.GetAsUnixTime($bLocalTime)
$json.AppendInt("tokenCreateTimeUtc",$dtNow)

# Examine the access token and save to a file.
$("Access Token: " + $json.StringOf("access_token"))
$("Full JSON Response:")
$($json.Emit())

$sbResponse = New-Object Chilkat.StringBuilder
$sbResponse.Append($json.Emit())
$bEmitBom = $false
$sbResponse.WriteFile("qa_data/tokens/paypal.json","utf-8",$bEmitBom)