(Perl) 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 Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

# 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 = chilkat::CkRest->new();

# 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 = 1;
$success = $rest->Connect("api.sandbox.paypal.com",443,1,$bAutoReconnect);
if ($success != 1) {
    print $rest->lastErrorText() . "\r\n";
    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->get_LastMethodSuccess() != 1) {
    print $rest->lastErrorText() . "\r\n";
    exit;
}

print $rest->lastRequestHeader() . "\r\n";

# 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 = chilkat::CkJsonObject->new();
$json->Load($responseStr);
$json->put_EmitCompact(0);

# Check the response status code.  A 200 indicates success..
if ($rest->get_ResponseStatusCode() != 200) {
    print $json->emit() . "\r\n";
    print "Failed." . "\r\n";
    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 = chilkat::CkDateTime->new();
$bLocalTime = 0;
$dtNow = $dateTime->GetAsUnixTime($bLocalTime);
$json->AppendInt("tokenCreateTimeUtc",$dtNow);

# Examine the access token and save to a file.
print "Access Token: " . $json->stringOf("access_token") . "\r\n";
print "Full JSON Response:" . "\r\n";
print $json->emit() . "\r\n";

$sbResponse = chilkat::CkStringBuilder->new();
$sbResponse->Append($json->emit());
$bEmitBom = 0;
$sbResponse->WriteFile("qa_data/tokens/paypal.json","utf-8",$bEmitBom);