There is definitely a problem with the Instagram OAuth flow. The returned authorization code doesn't seem to work for some reason, it's very likely a network related problem that they need to fix on their end.
My theory is that the authorization code generated is not distributed to all Instagram API servers, and if you happen to hit a bad node then you're out of luck.
However, I recently found a solution that doesn't rely on the authorization code. If you use the client-side authentication then you'll be able to retrieve the access token without ever using the authorization code. It's less secure but works great as a temporary fix.
You simply change response_type=code
to response_type=token
. The token response type will redirect the user back to your website using this URL structure:
http://your-redirect-uri#access_token=ACCESS-TOKEN
I recommend fetching the access token from the URL client-side using JavaScript, and then passing it to an endpoint on your website. E.g. /callback?accesstoken={accessToken}
. This is required because the content in the hash is not passed to the server.
Example:
<script>
if (window.location.hash && window.location.hash.indexOf('#access_token=') !== -1) {
var accessToken = window.location.hash.replace('#access_token=', '');
window.location.href = '/callback?accesstoken=' + accessToken;
}
</script>
The code snippet above is copied and slightly modified from the solution at https://news.ycombinator.com/item?id=13178789
You can read more about Instagram client side authentication on https://www.instagram.com/developer/authentication/ under Client-Side (Implicit) Authentication