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Rust

Constant Contact (v3) OAuth2 Access Token

See more Constant Contact Examples

Gets an OAuth2 access token for ConstantContact.

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Rust

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

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

// This should be the port in the localhost callback URL for your app.  
// The callback URL would look like "http://localhost:3017/" if the port number is 3017.
// Make sure when defining your application (i.e. "My Applications" at  https://app.constantcontact.com/pages/dma/portal/)
// that the Redirect URI is exactly this:  "http://localhost:3017/".   You may use any port number as long as it agrees
// with the ListenPort here.  It is important to use "http" and not "https" in the callback URI.  The trailing "/" is also important.
oauth2.set_listen_port(3017);

oauth2.set_authorization_endpoint("https://api.cc.email/v3/idfed");
oauth2.set_token_endpoint("https://idfed.constantcontact.com/as/token.oauth2");

// Replace these with actual values.
oauth2.set_client_id("CLIENT_KEY");
oauth2.set_client_secret("CLIENT_SECRET");

// Add one or more SPACE separated scopes
oauth2.set_scope("account_read account_update contact_data campaign_data");

// Begin the OAuth2 three-legged 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);

// Launch the system's default browser navigated to the URL.
if oauth2.launch_browser(&url).is_err() {
    println!("{}", oauth2.last_error_text());
    return;
}

// Now wait for the authorization.
// We'll wait for a max of 30 seconds.
let mut num_ms_waited = 0;
while (num_ms_waited < 30000) && (oauth2.auth_flow_state() < 3) {
    oauth2.sleep_ms(100);
    num_ms_waited = num_ms_waited + 100;
}

// If there was no response from the browser within 30 seconds, then 
// the AuthFlowState will be equal to 1 or 2.
// 1: Waiting for Redirect. The OAuth2 background thread is waiting to receive the redirect HTTP request from the browser.
// 2: Waiting for Final Response. The OAuth2 background thread is waiting for the final access token response.
// In that case, cancel the background task started in the call to StartAuth.
if oauth2.auth_flow_state() < 3 {
    let _ = oauth2.cancel();
    println!("No response from the browser!");
    return;
}

// Check the AuthFlowState to see if authorization was granted, denied, or if some error occurred
// The possible AuthFlowState values are:
// 3: Completed with Success. The OAuth2 flow has completed, the background thread exited, and the successful JSON response is available in AccessTokenResponse property.
// 4: Completed with Access Denied. The OAuth2 flow has completed, the background thread exited, and the error JSON is available in AccessTokenResponse property.
// 5: Failed Prior to Completion. The OAuth2 flow failed to complete, the background thread exited, and the error information is available in the FailureInfo property.
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;
}

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

// Get the full JSON response:
let json = chilkat::JsonObject::new();
let _ = json.load(&oauth2.access_token_response());
json.set_emit_compact(false);

// The JSON response looks like this:

// {
//   "access_token": "aEr4czHReESHUGcc2LRknzsMxUbW",
//   "refresh_token": "s2qH27ikM7r3Ia0LrZGDOIgKw0bubUotBdJ7fTtc7y",
//   "token_type": "Bearer"
// }

println!("{}", json.emit().unwrap_or_default());

// Save the JSON to a file for future requests.
let fac = chilkat::FileAccess::new();
let _ = fac.write_entire_text_file("qa_data/tokens/constantContact.json", &json.emit().unwrap_or_default(), "utf-8", false);