shootismoke/backend

import { chain } from '@amaurym/now-middleware';
import { NowRequest, NowResponse } from '@vercel/node';
import { Expo, ExpoPushSuccessTicket } from 'expo-server-sdk';

import { PushTicket } from '../models';
import {
    expoMessageForUser,
    findUsersForNotifications,
    isPromiseFulfilled,
    isPromiseRejected,
    sendBatchToExpo,
    whitelistIPMiddleware,
} from '../push';
import { connectToDatabase, logger, sentrySetup } from '../util';

sentrySetup();

/**
 * Send push notifications to all relevant users.
 */
export async function push(_req: NowRequest, res: NowResponse): Promise<void> {
    try {
        await connectToDatabase(process.env.MONGODB_ATLAS_URI);

        // Fetch all users to whom we should show a notification
        const users = await findUsersForNotifications();

        // Craft a push notification message for each user
        const messages = await Promise.allSettled(
            users.map(expoMessageForUser)
        );

        // Log the users with errors
        messages
            .filter(isPromiseRejected)
            .map(({ reason }) => reason as string)
            .forEach((error) => logger.error(new Error(error)));

        // Find the messages that are valid
        const validMessages = messages.filter(isPromiseFulfilled);
        // Send the valid messages to Expo Push Server, we get the tickets
        const tickets = await sendBatchToExpo(
            new Expo(),
            validMessages.map(({ value: { pushMessage } }) => pushMessage)
        );
        await PushTicket.insertMany(
            tickets.map((ticket, index) => ({
                ...ticket,
                receiptId: (ticket as ExpoPushSuccessTicket).id,
                userId: validMessages[index].value.userId,
            }))
        );

        res.send({
            status: 'ok',
            details: `Successfully sent ${validMessages.length}/${messages.length} push notifications`,
        });
    } catch (error) {
        logger.error(error);

        res.status(500);
        res.send({
            status: 'error',
            details: error.message,
        });
    }
}

export default chain(whitelistIPMiddleware)(push);