如何在不使用SDK的情况下获取Facebook用户访问令牌？

Question

I'm trying to get facebook user access token using Login Dialog and without using Javascript SDK.

fetch(`https://www.facebook.com/v2.12/dialog/oauth?
client_id=APP_ID
&redirect_uri=https://www.facebook.com/connect/login_success.html
&scope=manage_pages,publish_pages
&response_type=token`, {
mode: 'no-cors',
});

It redirects to https://www.facebook.com/login.php and has cancel_url param:

cancel_url: "https://www.facebook.com/connect/login_success.html?error=access_denied&error_code=200&error_description=Permissions+error&error_reason=user_denied#_=_"

But I didn't cancelled login, no login window at all. Why this error happens and how to fix it?

Answer 1

https://developers.facebook.com/docs/facebook-login/manually-build-a-login-flow#login

Your app must initiate a redirect to an endpoint which will display the login dialog...

You have to redirect to that URL, instead of trying to use it with an AJAX call. Also, make sure you are using a valid App ID ( client_id=APP_ID ).