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C++

USPS OAuth2 Client Credentials

See more OAuth2 Examples

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

Chilkat C++ Downloads

C++
#include <CkHttp.h>
#include <CkHttpRequest.h>
#include <CkHttpResponse.h>
#include <CkStringBuilder.h>
#include <CkJsonObject.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkHttp http;

    // 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

    CkHttpRequest req;
    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");

    CkHttpResponse resp;
    success = http.HttpReq("https://apis.usps.com/oauth2/v3/token",req,resp);
    if (success == false) {
        std::cout << http.lastErrorText() << "\r\n";
        return;
    }

    CkStringBuilder sbResponseBody;
    resp.GetBodySb(sbResponseBody);

    CkJsonObject jResp;
    jResp.LoadSb(sbResponseBody);
    jResp.put_EmitCompact(false);

    std::cout << "Response Body:" << "\r\n";
    std::cout << jResp.emit() << "\r\n";

    int respStatusCode = resp.get_StatusCode();
    std::cout << "Response Status Code = " << respStatusCode << "\r\n";
    if (respStatusCode >= 400) {
        std::cout << "Response Header:" << "\r\n";
        std::cout << resp.header() << "\r\n";
        std::cout << "Failed." << "\r\n";
        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

    // Chilkat functions returning "const char *" return a pointer to temporary internal memory owned and managed by Chilkat.
    // See this example explaining how this memory should be used: const char * functions.

    const char *access_token = jResp.stringOf("access_token");
    const char *token_type = jResp.stringOf("token_type");
    int issued_at = jResp.IntOf("issued_at");
    int expires_in = jResp.IntOf("expires_in");
    const char *status = jResp.stringOf("status");
    const char *scope = jResp.stringOf("scope");
    const char *issuer = jResp.stringOf("issuer");
    const char *client_id = jResp.stringOf("client_id");
    const char *application_name = jResp.stringOf("application_name");
    const char *api_products = jResp.stringOf("api_products");
    const char *public_key = jResp.stringOf("public_key");
    }