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JavaScript Requires Chilkat v10.1.2+

Facebook OAuth2 Access Token

See more Facebook Examples

Demonstrates how to get a Facebook OAuth2 access token from a desktop application or script.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
var success = false;

//  To further clarify, see OAuth 2.0 Authorization Flow

var oauth2 = new CkOAuth2();

//  This should match the Site URL configured for your Facebook APP, such as "http://localhost:3017/"
oauth2.ListenPort = 3017;

oauth2.AuthorizationEndpoint = "https://www.facebook.com/dialog/oauth";
oauth2.TokenEndpoint = "https://graph.facebook.com/oauth/access_token";

//  Replace this with your actual App ID
oauth2.ClientId = "APP_ID";

//  Set the Scope to a comma-separated list of permissions the app wishes to request.
//  See https://developers.facebook.com/docs/facebook-login/permissions/ for a full list of permissions.
oauth2.Scope = "public_profile,user_friends,email,user_posts,user_likes,user_photos";

//  This is for Require Proof Key for Code Exchange (PKCE)
//  See OAuth2 PKCE Explained
oauth2.CodeChallenge = true;
oauth2.CodeChallengeMethod = "S256";

//  Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
var url = oauth2.StartAuth();
if (oauth2.LastMethodSuccess !== true) {
    console.log(oauth2.LastErrorText);
    return;
}

console.log("url = " + url);

//  Launch the default browser on the system and navigate to the url.
//  The LaunchBrowser method was added in Chilkat v10.1.2.
success = oauth2.LaunchBrowser(url);
if (success == false) {
    console.log(oauth2.LastErrorText);
    return;
}

//  Wait for the user to approve or deny authorization in the browser.
var numMsWaited = 0;
while ((numMsWaited < 90000) && (oauth2.AuthFlowState < 3)) {
    oauth2.SleepMs(100);
    numMsWaited = numMsWaited+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.AuthFlowState < 3) {
    oauth2.Cancel();
    console.log("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.AuthFlowState == 5) {
    console.log("OAuth2 failed to complete.");
    console.log(oauth2.FailureInfo);
    return;
}

if (oauth2.AuthFlowState == 4) {
    console.log("OAuth2 authorization was denied.");
    console.log(oauth2.AccessTokenResponse);
    return;
}

if (oauth2.AuthFlowState !== 3) {
    console.log("Unexpected AuthFlowState:" + oauth2.AuthFlowState);
    return;
}

console.log("OAuth2 authorization granted!");
console.log("Access Token = " + oauth2.AccessToken);