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PHP Extension

USPS OAuth2 Client Credentials

See more OAuth2 Examples

Get an OAuth2 access token for the United States Postal Service (USPS) REST API.

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$success = false;

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

$http = new CkHttp();

// Implements the following CURL command:

// curl -X POST https://apis.usps.com/oauth2/v3/token \
//   -H "Content-Type: application/x-www-form-urlencoded" \
//   -d "grant_type=client_credentials" \
//   -d "client_id=123456789" \
//   -d "client_secret=A1B2C3D4E5" \
//   -d "scope=ResourceA+ResourceB+ResourceC"

// Use the following online tool to generate HTTP code from a CURL command
// Convert a cURL Command to HTTP Source Code

$req = new CkHttpRequest();
$req->AddParam('grant_type','client_credentials');
$req->AddParam('client_id','123456789');
$req->AddParam('client_secret','A1B2C3D4E5');
$req->AddParam('scope','ResourceA+ResourceB+ResourceC');

$req->put_HttpVerb('POST');
$req->put_ContentType('application/x-www-form-urlencoded');

$resp = new CkHttpResponse();
$success = $http->HttpReq('https://apis.usps.com/oauth2/v3/token',$req,$resp);
if ($success == false) {
    print $http->lastErrorText() . "\n";
    exit;
}

$sbResponseBody = new CkStringBuilder();
$resp->GetBodySb($sbResponseBody);

$jResp = new CkJsonObject();
$jResp->LoadSb($sbResponseBody);
$jResp->put_EmitCompact(false);

print 'Response Body:' . "\n";
print $jResp->emit() . "\n";

$respStatusCode = $resp->get_StatusCode();
print 'Response Status Code = ' . $respStatusCode . "\n";
if ($respStatusCode >= 400) {
    print 'Response Header:' . "\n";
    print $resp->header() . "\n";
    print 'Failed.' . "\n";
    exit;
}

// Sample JSON response:
// (Sample code for parsing the JSON response is shown below)

// {
//   "access_token": "eyJraWQiOiIxMDEwMTAiLCJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9.eyJzdWIiOiIiLCJhdWQiOiJhZGRyZXNzZXMgaW50ZXJuYXRpb25hbC1wcmljZXMgc3Vic2NyaXB0aW9ucyBwYXltZW50cyBwaWNrdXAgdHJhY2tpbmcgbGFiZWxzIHNjYW4tZm9ybXMgY29tcGFuaWVzIHNlcnZpY2UtZGVsaXZlcnktc3RhbmRhcmRzIGxvY2F0aW9ucyBpbnRlcm5hdGlvbmFsLWxhYmVscyBwcmljZXMiLCJhenAiOiJoeXI3YjN2Q1J0cFl0QUhNMWE4Y2RVcmt5eUZtTmtiZyIsIm9yZ2FuaXphdGlvbl9pZCI6IjAiLCJpc3MiOiJ1cm46XC9cL2FwaS51c3BzLmNvbSIsImV4cCI6MTY4MDkxNzc4NiwiaWF0IjoxNjgwODg4OTg2LCJqdGkiOiI3YjU5MzJlMS05NjIxLTQzZDAtYTMyNy0xMzIxYWVjNzJjZGYifQ.QzrUxlT2rG4jvYbMDGnk23j8ZYfHJcdXPKR9CbSmcKeVpURaHhEMpPB6K4x5ut3xxeEGSzeE5VRz8vixI4iqyHsD8rSdkLTPHy0iovUHOZQBAJVQ6hii9jpLhxUXmiTtH3jKzSj_f2fuNmZbIGhf-CR2FBeWF-aBPzEDEMV95nkCUMfW_Z2BmkbraSfvQZxkCO-cLrMAwlYcrzUtaJ7vnazeQB4sep5BBHBEvsa4kfq6_tz6BAKgv3R7cI2NkSv-wgy_IGoTjVCMTS8mJHGs_t8cWCO8-z4lxW1tUwIBKOCUDpmEEnGgiG6Sl0C_gGl4bZ5cDSl4IgPpcOVi9jZ7LA",
//   "token_type": "Bearer",
//   "issued_at": 1680888985929,
//   "expires_in": 28799,
//   "status": "approved",
//   "scope": "addresses international-prices subscriptions payments pickup tracking labels scan-forms companies service-delivery-standards locations international-labels prices",
//   "issuer": "api.usps.com",
//   "client_id": "hyr7b3vCRtpYtAHM1a8cdUrkyyFmNkbg",
//   "application_name": "Silver Shipper Developer",
//   "api_products": "[Shipping-Silver]",
//   "public_key": "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"
// }

// Sample code for parsing the JSON response...
// Use the following online tool to generate parsing code from sample JSON:
// Generate Parsing Code from JSON

$access_token = $jResp->stringOf('access_token');
$token_type = $jResp->stringOf('token_type');
$issued_at = $jResp->IntOf('issued_at');
$expires_in = $jResp->IntOf('expires_in');
$status = $jResp->stringOf('status');
$scope = $jResp->stringOf('scope');
$issuer = $jResp->stringOf('issuer');
$client_id = $jResp->stringOf('client_id');
$application_name = $jResp->stringOf('application_name');
$api_products = $jResp->stringOf('api_products');
$public_key = $jResp->stringOf('public_key');

?>