swaf/src/components/ExpressAppComponent.ts

import ApplicationComponent from "../ApplicationComponent";
import express, {Express, Router} from "express";
import Logger from "../Logger";
import {Server} from "http";
import compression from "compression";

export default class ExpressAppComponent extends ApplicationComponent<void> {
    private readonly addr: string;
    private readonly port: number;
    private server?: Server;
    private expressApp?: Express;

    public constructor(addr: string, port: number) {
        super();
        this.addr = addr;
        this.port = port;
    }

    public async start(app: Express): Promise<void> {
        this.server = app.listen(this.port, this.addr, () => {
            Logger.info(`Web server running on ${this.addr}:${this.port}.`);
        });

        // Proxy
        app.set('trust proxy', 'loopback');

        this.expressApp = app;
    }

    public async init(router: Router): Promise<void> {
        router.use(express.json({
            type: req => req.headers['content-type']?.match(/^application\/(.+\+)?json$/)
        }));
        router.use(express.urlencoded({
            extended: true,
        }));

        // gzip
        router.use(compression());

        router.use((req, res, next) => {
            req.models = {};
            req.modelCollections = {};
            next();
        });
    }

    public async stop(): Promise<void> {
        if (this.server) {
            await this.close('Webserver', this.server, this.server.close);
        }
    }

    public getServer(): Server {
        if (!this.server) throw 'Server was not initialized.';
        return this.server;
    }

    public getExpressApp(): Express {
        return this.expressApp!;
    }
}