Rust

Get Google Cloud Storage Access Token using Service Account JSON Private Key

See more Google Cloud Storage Examples

Demonstrates how to get a Google Cloud Storage access token using a JSON service account private key. Obtaining an access token for a service account requires no user interaction (it does not require a browser, nor callback URI's, etc.).

When an access token expires, an application can be (and should be) designed to automatically fetch a new access token.

Rust

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

// First load the JSON key into a string.
let fac = chilkat::FileAccess::new();
let Ok(json_key) = fac.read_entire_text_file("qa_data/googleApi/ChilkatCloud-13a07a2e8b3f.json", "utf-8") else {
    println!("{}", fac.last_error_text());
    return;
};

// A JSON private key should look something like this:

// 	{
// 	  "type": "service_account",
// 	  "project_id": "chilkattest-1350",
// 	  "private_key_id": "fa2e36ee26986eab628b59868af8bec1d1c64c38",
// 	  "private_key": "-----BEGIN PRIVATE KEY-----\nMIIEvgIjFa...28N64N2n1E4FYzBZjSdy\n-----END PRIVATE KEY-----\n",
// 	  "client_email": "598922945226-00rb0ppfg0sndajo6bhvd4v17jtj2d3a@developer.gserviceaccount.com",
// 	  "client_id": "598922945226-00rb0ppfg0snd9jo7bhvd4v17jtj2d3a.apps.googleusercontent.com",
// 	  "auth_uri": "https://accounts.google.com/o/oauth2/auth",
// 	  "token_uri": "https://accounts.google.com/o/oauth2/token",
// 	  "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
// 	  "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/598922945226-00rb0ppfg0sndajo6bhvd4v17jtj2d3a%40developer.gserviceaccount.com"
// 	}

let g_auth = chilkat::AuthGoogle::new();
g_auth.set_json_key(&json_key);

// Choose a scope.
g_auth.set_scope("https://www.googleapis.com/auth/cloud-platform");

// Request an access token that is valid for this many seconds.
g_auth.set_expire_num_seconds(3600);

// If the application is requesting delegated access:
// The email address of the user for which the application is requesting delegated access,
// then set the email address here. (Otherwise leave it empty.)
g_auth.set_sub_email_address("");

// Connect to www.googleapis.com using TLS (TLS 1.2 is the default.)
// The Chilkat socket object is used so that the connection can be established
// through proxies or an SSH tunnel if desired.
let tls_sock = chilkat::Socket::new();
if tls_sock.connect("www.googleapis.com", 443, true, 5000).is_err() {
    println!("{}", tls_sock.last_error_text());
    return;
}

// Send the request to obtain the access token.
if g_auth.obtain_access_token(&tls_sock).is_err() {
    println!("{}", g_auth.last_error_text());
    return;
}

// Examine the access token:
println!("Access Token: {}", g_auth.access_token());

// We're going to save this access token to a file to be used
// by other examples.
let sb_token = chilkat::StringBuilder::new();
let _ = sb_token.append(&g_auth.access_token());
let _ = sb_token.write_file("qa_data/tokens/googleCloudStorageAccessToken.txt", "utf-8", false);