Rust Requires Chilkat v10.1.2+

Schwab OAuth2 in a Desktop App

See more Schwab Examples

Demonstrates how to get a Charles Schwab OAuth2 access token from a desktop application or script. Rust

// To further clarify, see OAuth 2.0 Authorization Flow

// This is the way to initially obtain the OAuth2 access token.  Afterwards it can be 
// repeatedly refreshed without user interaction, as shown in this example: Refresh Schwab OAuth2 Access Token.

let oauth2 = chilkat::OAuth2::new();

// Your applicaton must use your own public web server as an intermediate
// to receive and forward the redirect to localhost.
// See Using Your Web Server as an Intermediary for OAuth2 Redirect to localhost

oauth2.set_app_callback_url("https://yourwebserver.com/OAuth2.php");
oauth2.set_listen_port(3017);

oauth2.set_authorization_endpoint("https://api.schwabapi.com/v1/oauth/authorize");
oauth2.set_token_endpoint("https://api.schwabapi.com/v1/oauth/token");

// Replace these with actual values.
oauth2.set_client_id("APP_KEY");
oauth2.set_client_secret("APP_SECRET");
oauth2.set_use_basic_auth(true);
oauth2.set_code_challenge(false);

oauth2.set_scope("");

// Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
let Ok(url) = oauth2.start_auth() else {
    println!("{}", oauth2.last_error_text());
    return;
};

println!("url = {}", url);

// Launch the default browser on the system and navigate to the url.
// The LaunchBrowser method was added in Chilkat v10.1.2.
if oauth2.launch_browser(&url).is_err() {
    println!("{}", oauth2.last_error_text());
    return;
}

// Wait for the user to approve or deny authorization in the browser.
let mut num_ms_waited = 0;
while (num_ms_waited < 90000) && (oauth2.auth_flow_state() < 3) {
    oauth2.sleep_ms(100);
    num_ms_waited = num_ms_waited + 100;
}

// If the browser does not respond within the specified time, AuthFlowState will be:
// 
// 1: Waiting for Redirect – The OAuth2 background thread is waiting for the browser's redirect request.
// 2: Waiting for Final Response – The thread is awaiting the final access token response.
// In either case, cancel the background task initiated by StartAuth.

if oauth2.auth_flow_state() < 3 {
    let _ = oauth2.cancel();
    println!("No response from the browser!");
    return;
}

// Check AuthFlowState to determine if authorization was granted, denied, or failed:
// 
// 3: Success – OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
// 4: Access Denied – OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
// 5: Failure – OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

if oauth2.auth_flow_state() == 5 {
    println!("OAuth2 failed to complete.");
    println!("{}", oauth2.failure_info());
    return;
}

if oauth2.auth_flow_state() == 4 {
    println!("OAuth2 authorization was denied.");
    println!("{}", oauth2.access_token_response());
    return;
}

if oauth2.auth_flow_state() != 3 {
    println!("Unexpected AuthFlowState:{}", oauth2.auth_flow_state());
    return;
}

// Save the full JSON access token response to a file.
let sb_json = chilkat::StringBuilder::new();
let _ = sb_json.append(&oauth2.access_token_response());
let _ = sb_json.write_file("qa_data/tokens/schwab-access-token.json", "utf-8", false);

// The full JSON received looks like this:
// {
//   "expires_in": 3600,
//   "x_refresh_token_expires_in": 8726400,
//   "refresh_token": "L011546037639r ... 3vR2DrbOmg0Sdagw",
//   "access_token": "eyJlbmMiOiJBMTI4Q0 ... oETJEMbeggg",
//   "token_type": "bearer"
// }

println!("OAuth2 authorization granted!");
println!("Access Token = {}", oauth2.access_token());