Authentication

@using Skybrud.Social.GitHub.OAuth
@using Skybrud.Social.GitHub.Responses.Authentication
@using Skybrud.Social.GitHub.Scopes
@inherits WebViewPage

@{
    
    // Initialize a new instance of the OAuth client
    GitHubOAuthClient client = new GitHubOAuthClient {
        ClientId = "Your client ID",
        ClientSecret = "Your client secret",
        RedirectUri = "Your redirect URI"
    };
    
    // Read some input from the query string
    string code = Request.QueryString["code"];
    string state = Request.QueryString["state"];
    string action = Request.QueryString["do"];
    string error = Request.QueryString["error"];
    string errorDescription = Request.QueryString["error_description"];

    // Handle the state when the user clicks our login button
    if (action == "login") {

        // Generate a random scope
        state = Guid.NewGuid().ToString();

        // Generate the session key for the state
        string stateKey = "GitHubOAuthState_" + state;

        // Store the state in the session of the user
        Session[stateKey] = Request.RawUrl;

        // Declare a list of scopes to request from the user
        GitHubScopeCollection scopes = new GitHubScopeCollection {
            GitHubScopes.User,
            GitHubScopes.UserEmail
        };

        // Generate the authorization URL
        string authorizationUrl = client.GetAuthorizationUrl(state, scopes);

        // Redirect the user
        Response.Redirect(authorizationUrl);

    } else if (!string.IsNullOrWhiteSpace(error)) {

        // Remove the session
        if (state != null) {
            Session.Remove("GitHubOAuthState_" + state);
        }

        // Print out the error
        <div class="alert alert-danger"><strong>@error</strong><br />@errorDescription</div>

        return;

    } else if (Request.QueryString["code"] != null) {

        // Generate the session key for the state
        string stateKey = "GitHubOAuthState_" + state;

        if (Session[stateKey] == null) {
            <p>Has your session expired?</p>
            <p>
                <a class="btn btn-default" href="?do=login">Re-try login</a>
            </p>
            return;
        }

        GitHubTokenResponse response = client.GetAccessTokenFromAuthorizationCode(code);

        <p><strong>Access Token</strong></p>
        <textarea>@(string.IsNullOrWhiteSpace(response.Body.AccessToken) ? "Empty" : response.Body.AccessToken)</textarea>

        return;

    }

    <p>
        <a class="btn btn-default" href="?do=login">Login with GitHub</a>
    </p>

}