jannes-io/stock-alerts.js

## stock-alerts.js
import './env';
import 'reflect-metadata';
import { launch, Page } from 'puppeteer';
import { Connection } from 'typeorm';
import * as AWS from 'aws-sdk';
import { SendEmailRequest } from 'aws-sdk/clients/ses';
import { establishDbConnection } from './services';
import { Alert, AlertType } from './entities';

AWS.config.update({
  region: 'eu-west-1',
  credentials: {
    accessKeyId: process.env.AWS_ACCESS_KEY_ID,
    secretAccessKey: process.env.AWS_ACCESS_KEY_SECRET,
  },
});

const SESClient = new AWS.SES({ apiVersion: '2010-12-01' });

const sendMail = async (alert: Alert) => {
  let action = '';
  switch (alert.type) {
    case AlertType.STOP_LOSS:
    case AlertType.LIMIT_SELL:
      action = `SELL AT ${alert.price}`;
      break;
    case AlertType.LIMIT_BUY:
      action = `BUY AT ${alert.price}`;
      break;
    default:
  }

  const htmlBody = `
    <!DOCTYPE html>
    <html lang="en">
    <head></head>
    <body>
      <p>STOCK ALERT TRIGGERED</p>
      <p>type: ${alert.type}</p>
      <p>stock: ${alert.exchange} - ${alert.symbol}</p>
      <p>action: ${action}</p>
    </body>
    </html>
    `;

  const params: SendEmailRequest = {
    Destination: { ToAddresses: [process.env.SES_MAIL_TO] },
    Source: `stock alerts <${process.env.SES_MAIL_FROM}>`,
    Message: {
      Subject: {
        Charset: 'UTF-8',
        Data: `Stock alert triggered: ${alert.symbol} - ${action}`,
      },
      Body: {
        Html: {
          Charset: 'UTF-8',
          Data: htmlBody,
        },
      },
    },
  };

  try {
    await SESClient.sendEmail(params).promise();
  } catch (e) {
    console.error('Failed to send alert', e);
  }
};

const handleAlerts = async (page: Page, stock: string, alerts: Alert[]) => {
  const url = `https://www.tradingview.com/symbols/${stock}`;
  await page.goto(url);
  const selector = '.tv-symbol-price-quote__value span';
  const currentPriceStr = await page.$$eval(selector, (nodes) => nodes[0].innerHTML);
  const currentPrice = parseFloat(currentPriceStr);

  await Promise.all(alerts.map(async (alert) => {
    switch (alert.type) {
      case AlertType.LIMIT_SELL:
        if (currentPrice > alert.price) {
          await sendMail(alert);
        }
        break;
      case AlertType.LIMIT_BUY:
      case AlertType.STOP_LOSS:
        if (currentPrice < alert.price) {
          await sendMail(alert);
        }
        break;
      default:
    }
  }));
};

const watchStocks = async (db: Connection, page: Page) => {
  const allAlerts = await db.getRepository(Alert).find();
  const alertMap = allAlerts.reduce((acc: Record<string, Alert[]>, alert) => {
    const stock = `${alert.exchange}-${alert.symbol}`;
    if (acc[stock] === undefined) {
      acc[stock] = [];
    }
    acc[stock].push(alert);
    return acc;
  }, {});

  const alertPromises = Object
    .entries(alertMap)
    .map(([stock, alerts]) => handleAlerts(page, stock, alerts));

  await Promise.allSettled(alertPromises);
  // setTimeout(() => watchStocks(db), 5 * 60 * 1000);
};

const run = async () => {
  const browser = await launch();
  const page = await browser.newPage();
  const db = await establishDbConnection();
  await watchStocks(db, page);
  return browser;
};

run()
  .then((browser) => browser.close())
  .catch(console.error);
	import './env';
	import 'reflect-metadata';
	import { launch, Page } from 'puppeteer';
	import { Connection } from 'typeorm';
	import * as AWS from 'aws-sdk';
	import { SendEmailRequest } from 'aws-sdk/clients/ses';
	import { establishDbConnection } from './services';
	import { Alert, AlertType } from './entities';

	AWS.config.update({
	region: 'eu-west-1',
	credentials: {
	accessKeyId: process.env.AWS_ACCESS_KEY_ID,
	secretAccessKey: process.env.AWS_ACCESS_KEY_SECRET,
	},
	});

	const SESClient = new AWS.SES({ apiVersion: '2010-12-01' });

	const sendMail = async (alert: Alert) => {
	let action = '';
	switch (alert.type) {
	case AlertType.STOP_LOSS:
	case AlertType.LIMIT_SELL:
	action = `SELL AT ${alert.price}`;
	break;
	case AlertType.LIMIT_BUY:
	action = `BUY AT ${alert.price}`;
	break;
	default:
	}

	const htmlBody = `
	<!DOCTYPE html>
	<html lang="en">
	<head></head>
	<body>
	<p>STOCK ALERT TRIGGERED</p>
	<p>type: ${alert.type}</p>
	<p>stock: ${alert.exchange} - ${alert.symbol}</p>
	<p>action: ${action}</p>
	</body>
	</html>
	`;

	const params: SendEmailRequest = {
	Destination: { ToAddresses: [process.env.SES_MAIL_TO] },
	Source: `stock alerts <${process.env.SES_MAIL_FROM}>`,
	Message: {
	Subject: {
	Charset: 'UTF-8',
	Data: `Stock alert triggered: ${alert.symbol} - ${action}`,
	},
	Body: {
	Html: {
	Charset: 'UTF-8',
	Data: htmlBody,
	},
	},
	},
	};

	try {
	await SESClient.sendEmail(params).promise();
	} catch (e) {
	console.error('Failed to send alert', e);
	}
	};

	const handleAlerts = async (page: Page, stock: string, alerts: Alert[]) => {
	const url = `https://www.tradingview.com/symbols/${stock}`;
	await page.goto(url);
	const selector = '.tv-symbol-price-quote__value span';
	const currentPriceStr = await page.$$eval(selector, (nodes) => nodes[0].innerHTML);
	const currentPrice = parseFloat(currentPriceStr);

	await Promise.all(alerts.map(async (alert) => {
	switch (alert.type) {
	case AlertType.LIMIT_SELL:
	if (currentPrice > alert.price) {
	await sendMail(alert);
	}
	break;
	case AlertType.LIMIT_BUY:
	case AlertType.STOP_LOSS:
	if (currentPrice < alert.price) {
	await sendMail(alert);
	}
	break;
	default:
	}
	}));
	};

	const watchStocks = async (db: Connection, page: Page) => {
	const allAlerts = await db.getRepository(Alert).find();
	const alertMap = allAlerts.reduce((acc: Record<string, Alert[]>, alert) => {
	const stock = `${alert.exchange}-${alert.symbol}`;
	if (acc[stock] === undefined) {
	acc[stock] = [];
	}
	acc[stock].push(alert);
	return acc;
	}, {});

	const alertPromises = Object
	.entries(alertMap)
	.map(([stock, alerts]) => handleAlerts(page, stock, alerts));

	await Promise.allSettled(alertPromises);
	// setTimeout(() => watchStocks(db), 5 * 60 * 1000);
	};

	const run = async () => {
	const browser = await launch();
	const page = await browser.newPage();
	const db = await establishDbConnection();
	await watchStocks(db, page);
	return browser;
	};

	run()
	.then((browser) => browser.close())
	.catch(console.error);