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C++

Get Google Account Info from OAuth2 Access Token

See more Google APIs Examples

In the Google OAuth2 authorization flow, an application can know the email address of the Google account used to authorize access by requesting and processing user information from the Google UserInfo endpoint after obtaining an access token.

Chilkat C++ Downloads

C++
#include <CkHttp.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 -H "Authorization: Bearer YOUR_ACCESS_TOKEN" https://www.googleapis.com/oauth2/v3/userinfo

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

    // Adds the "Authorization: Bearer YOUR_ACCESS_TOKEN" header.
    http.put_AuthToken("YOUR_ACCESS_TOKEN");

    CkStringBuilder sbResponseBody;
    success = http.QuickGetSb("https://www.googleapis.com/oauth2/v3/userinfo",sbResponseBody);
    if (success == false) {
        std::cout << http.lastErrorText() << "\r\n";
        return;
    }

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

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

    int respStatusCode = http.get_LastStatus();
    std::cout << "Response Status Code = " << respStatusCode << "\r\n";
    if (respStatusCode >= 400) {
        std::cout << "Response Header:" << "\r\n";
        std::cout << http.lastHeader() << "\r\n";
        std::cout << "Failed." << "\r\n";
        return;
    }

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

    // {
    //   "sub": "112233445678901234567",
    //   "name": "John Doe",
    //   "given_name": "John",
    //   "family_name": "Doe",
    //   "profile": "https://plus.google.com/112233445678901234567",
    //   "picture": "https://lh3.googleusercontent.com/a-/AOh14GiU-EXAMPLE",
    //   "email": "johndoe@example.com",
    //   "email_verified": true,
    //   "locale": "en"
    // }

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

    const char *v_sub = jResp.stringOf("sub");
    const char *name = jResp.stringOf("name");
    const char *given_name = jResp.stringOf("given_name");
    const char *family_name = jResp.stringOf("family_name");
    const char *profile = jResp.stringOf("profile");
    const char *picture = jResp.stringOf("picture");
    const char *email = jResp.stringOf("email");
    bool email_verified = jResp.BoolOf("email_verified");
    const char *locale = jResp.stringOf("locale");
    }