MuDBase/server/endpoints/ModifySongEndpointHandler.ts

const models = require('../models');
import * as api from '../../client/src/api';
import { EndpointError, EndpointHandler, catchUnhandledErrors } from './types';

export const ModifySongEndpointHandler: EndpointHandler = async (req: any, res: any) => {
    if (!api.checkModifySongRequest(req)) {
        const e: EndpointError = {
            internalMessage: 'Invalid ModifySong request: ' + JSON.stringify(req.body),
            httpStatus: 400
        };
        throw e;
    }
    const reqObject: api.ModifySongRequest = req.body;

    // Start retrieving the artist instances to link the song to.
    var artistInstancePromises: Promise<any>[] = [];
    reqObject.artistIds?.forEach((artistId: Number) => {
        artistInstancePromises.push(
            models.Artist.findAll({
                where: { id: artistId }
            })
                .then((artist: any[]) => {
                    if (artist.length != 1) {
                        const e: EndpointError = {
                            internalMessage: 'There is no artist with id ' + artistId + '.',
                            httpStatus: 400
                        };
                        throw e;
                    }
                    return artist[0];
                })
        );
    });
    var artistInstancesPromise = Promise.all(artistInstancePromises);

    // Start retrieving the album instances to link the song to.
    var albumInstancePromises: Promise<any>[] = [];
    reqObject.albumIds?.forEach((albumId: Number) => {
        albumInstancePromises.push(
            models.Album.findAll({
                where: { id: albumId }
            })
                .then((album: any[]) => {
                    if (album.length != 1) {
                        const e: EndpointError = {
                            internalMessage: 'There is no album with id ' + albumId + '.',
                            httpStatus: 400
                        };
                        throw e;
                    }
                    return album[0];
                })
        );
    });
    var albumInstancesPromise = Promise.all(albumInstancePromises);

    // Start retrieving the song to modify.
    var songInstancePromise: Promise<any> =
        models.Song.findAll({
            where: { id: reqObject.id }
        })
            .then((song: any[]) => {
                if (song.length != 1) {
                    const e: EndpointError = {
                        internalMessage: 'There is no song with id ' + reqObject.id + '.',
                        httpStatus: 400
                    };
                    throw e;
                }
                return song[0];
            });

    // Upon finish retrieving artists and albums, create the song and associate it.
    await Promise.all([artistInstancesPromise, albumInstancesPromise, songInstancePromise])
        .then(async (values: any) => {
            var [artists, albums, song] = values;
            song.setArtists(artists);
            song.setAlbums(albums);
            song.setTitle(reqObject.title);
            await song.save();
        })
        .then(() => {
            res.status(200).send({});
        })
        .catch(catchUnhandledErrors);
}