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Objective-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 Objective-C Downloads

Objective-C
#import <CkoHttp.h>
#import <CkoStringBuilder.h>
#import <CkoJsonObject.h>
#import <NSString.h>

BOOL success = NO;

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

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

// 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.AuthToken = @"YOUR_ACCESS_TOKEN";

CkoStringBuilder *sbResponseBody = [[CkoStringBuilder alloc] init];
success = [http QuickGetSb: @"https://www.googleapis.com/oauth2/v3/userinfo" sbContent: sbResponseBody];
if (success == NO) {
    NSLog(@"%@",http.LastErrorText);
    return;
}

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

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

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

NSString *v_sub = [jResp StringOf: @"sub"];
NSString *name = [jResp StringOf: @"name"];
NSString *given_name = [jResp StringOf: @"given_name"];
NSString *family_name = [jResp StringOf: @"family_name"];
NSString *profile = [jResp StringOf: @"profile"];
NSString *picture = [jResp StringOf: @"picture"];
NSString *email = [jResp StringOf: @"email"];
BOOL email_verified = [jResp BoolOf: @"email_verified"];
NSString *locale = [jResp StringOf: @"locale"];