noctbot/web/src/routes/login/discord.ts

import { Request as ExpressRequest, Response as ExpressResponse } from "express";
import { OAuth2 } from "src/utils/util";
import { ENVIRONMENT } from "src/utils/environment";
import { Option } from "@shared/common/async_utils";
import { logger } from "src/utils/logging";

export const get = async (req: ExpressRequest, res: ExpressResponse): Promise<void> => {
    res.redirect(OAuth2.getAuthUrl({
        client_id: ENVIRONMENT.clientId,
        redirect_url: ENVIRONMENT.redirectUrl,
        response_type: "code",
        scope: "identify",
    }));
};

type AuthResult = Option<unknown, {error: string}>;

export const post = async (req: ExpressRequest, res: ExpressResponse):
                                Promise<ExpressResponse<AuthResult>> => {
    if (!req.session) {
        logger.error("WEB: req.session is not set up correctly!");
        return res.json({
            ok: false,
            error: "No session is set up. This is a server error!",
        });
    }
    if (!req.session.authTokenCode) {
        logger.error("WEB: attempted to join with no authTokenCode set!");
        return res.json({
            ok: false,
            error: "Authentication token is missing. Please try logging in again.",
        });
    }
    const result = await OAuth2.getToken({
        client_id: ENVIRONMENT.clientId,
        client_secret: ENVIRONMENT.clientSecret,
        grant_type: "authorization_code",
        code: req.session.authTokenCode,
        scope: "identify",
        redirect_uri: ENVIRONMENT.redirectUrl,
    });
    if (!result.ok) {
        return res.json(result);
    }
    req.sessionOptions.maxAge = result.expires_in;
    return res.json({
        ok: true,
    });
};