(Objective-C) USPS OAuth2 Client Credentials

See more OAuth2 Examples

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

For more information, see https://developers.usps.com/api/81

Chilkat Objective-C Library Downloads MAC OS X (Cocoa) Libs iOS Libs

#import <CkoHttp.h>
#import <CkoHttpRequest.h>
#import <CkoHttpResponse.h>
#import <CkoStringBuilder.h>
#import <CkoJsonObject.h>
#import <NSString.h>

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

CkoHttp *http = [[CkoHttp alloc] init];
BOOL success;

// 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

CkoHttpRequest *req = [[CkoHttpRequest alloc] init];
[req AddParam: @"grant_type" value: @"client_credentials"];
[req AddParam: @"client_id" value: @"123456789"];
[req AddParam: @"client_secret" value: @"A1B2C3D4E5"];
[req AddParam: @"scope" value: @"ResourceA+ResourceB+ResourceC"];

CkoHttpResponse *resp = [http PostUrlEncoded: @"https://apis.usps.com/oauth2/v3/token" req: req];
if (http.LastMethodSuccess == NO) {
    NSLog(@"%@",http.LastErrorText);
    return;
}

CkoStringBuilder *sbResponseBody = [[CkoStringBuilder alloc] init];
[resp GetBodySb: sbResponseBody];

CkoJsonObject *jResp = [[CkoJsonObject alloc] init];
[jResp LoadSb: sbResponseBody];
jResp.EmitCompact = NO;

NSLog(@"%@",@"Response Body:");
NSLog(@"%@",[jResp Emit]);

int respStatusCode = [resp.StatusCode intValue];
NSLog(@"%@%d",@"Response Status Code = ",respStatusCode);
if (respStatusCode >= 400) {
    NSLog(@"%@",@"Response Header:");
    NSLog(@"%@",resp.Header);
    NSLog(@"%@",@"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

NSString *access_token = [jResp StringOf: @"access_token"];
NSString *token_type = [jResp StringOf: @"token_type"];
int issued_at = [[jResp IntOf: @"issued_at"] intValue];
int expires_in = [[jResp IntOf: @"expires_in"] intValue];
NSString *status = [jResp StringOf: @"status"];
NSString *scope = [jResp StringOf: @"scope"];
NSString *issuer = [jResp StringOf: @"issuer"];
NSString *client_id = [jResp StringOf: @"client_id"];
NSString *application_name = [jResp StringOf: @"application_name"];
NSString *api_products = [jResp StringOf: @"api_products"];
NSString *public_key = [jResp StringOf: @"public_key"];