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JavaScript

USPS OAuth2 Client Credentials

See more OAuth2 Examples

Get an OAuth2 access token for the United States Postal Service (USPS) REST API.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
var success = false;

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

var 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

var 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.HttpVerb = "POST";
req.ContentType = "application/x-www-form-urlencoded";

var resp = new CkHttpResponse();
success = http.HttpReq("https://apis.usps.com/oauth2/v3/token",req,resp);
if (success == false) {
    console.log(http.LastErrorText);
    return;
}

var sbResponseBody = new CkStringBuilder();
resp.GetBodySb(sbResponseBody);

var jResp = new CkJsonObject();
jResp.LoadSb(sbResponseBody);
jResp.EmitCompact = false;

console.log("Response Body:");
console.log(jResp.Emit());

var respStatusCode = resp.StatusCode;
console.log("Response Status Code = " + respStatusCode);
if (respStatusCode >= 400) {
    console.log("Response Header:");
    console.log(resp.Header);
    console.log("Failed.");
    return;
}

// 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

var access_token = jResp.StringOf("access_token");
var token_type = jResp.StringOf("token_type");
var issued_at = jResp.IntOf("issued_at");
var expires_in = jResp.IntOf("expires_in");
var status = jResp.StringOf("status");
var scope = jResp.StringOf("scope");
var issuer = jResp.StringOf("issuer");
var client_id = jResp.StringOf("client_id");
var application_name = jResp.StringOf("application_name");
var api_products = jResp.StringOf("api_products");
var public_key = jResp.StringOf("public_key");