web-check/server.js
2023-09-03 16:23:07 +01:00

149 lines
4.8 KiB
JavaScript

const express = require('express');
const fs = require('fs');
const path = require('path');
const cors = require('cors');
const historyApiFallback = require('connect-history-api-fallback');
require('dotenv').config();
const app = express();
const port = process.env.PORT || 3000; // The port to run the server on
const API_DIR = '/api'; // Name of the dir containing the lambda functions
const dirPath = path.join(__dirname, API_DIR); // Path to the lambda functions dir
const guiPath = path.join(__dirname, 'build');
const placeholderFilePath = path.join(__dirname, 'public', 'placeholder.html');
const handlers = {}; // Will store list of API endpoints
process.env.WC_SERVER = 'true'; // Tells middleware to return in non-lambda mode
// Enable CORS
app.use(cors({
origin: process.env.API_CORS_ORIGIN || '*',
}));
// Read and register each API function as an Express routes
fs.readdirSync(dirPath, { withFileTypes: true })
.filter(dirent => dirent.isFile() && dirent.name.endsWith('.js'))
.forEach(dirent => {
const routeName = dirent.name.split('.')[0];
const route = `${API_DIR}/${routeName}`;
const handler = require(path.join(dirPath, dirent.name));
handlers[route] = handler;
app.get(route, async (req, res) => {
try {
await handler(req, res);
} catch (err) {
res.status(500).json({ error: err.message });
}
});
});
// Create a single API endpoint to execute all lambda functions
app.get('/api', async (req, res) => {
const results = {};
const { url } = req.query;
const maxExecutionTime = process.env.API_TIMEOUT_LIMIT || 20000;
const executeHandler = async (handler, req, res) => {
return new Promise(async (resolve, reject) => {
try {
const mockRes = {
status: (statusCode) => mockRes,
json: (body) => resolve({ body }),
};
await handler({ ...req, query: { url } }, mockRes);
} catch (err) {
reject(err);
}
});
};
const timeout = (ms, jobName = null) => {
return new Promise((_, reject) => {
setTimeout(() => {
reject(new Error(
`Timed out after ${ms/1000} seconds${jobName ? `, when executing ${jobName}` : ''}`
));
}, ms);
});
};
const handlerPromises = Object.entries(handlers).map(async ([route, handler]) => {
const routeName = route.replace(`${API_DIR}/`, '');
try {
const result = await Promise.race([
executeHandler(handler, req, res),
timeout(maxExecutionTime, routeName)
]);
results[routeName] = result.body;
} catch (err) {
results[routeName] = { error: err.message };
}
});
await Promise.all(handlerPromises);
res.json(results);
});
// Handle SPA routing
app.use(historyApiFallback({
rewrites: [
{ from: /^\/api\/.*$/, to: (context) => context.parsedUrl.path },
]
}));
// Serve up the GUI - if build dir exists, and GUI feature enabled
if (process.env.DISABLE_GUI && process.env.DISABLE_GUI !== 'false') {
app.get('*', async (req, res) => {
const placeholderContent = await fs.promises.readFile(placeholderFilePath, 'utf-8');
const htmlContent = placeholderContent.replace(
'<!-- CONTENT -->',
'Web-Check API is up and running!<br />Access the endpoints at '
+'<a href="/api"><code>/api</code></a>'
);
res.status(500).send(htmlContent);
});
} else if (!fs.existsSync(guiPath)) {
app.get('*', async (req, res) => {
const placeholderContent = await fs.promises.readFile(placeholderFilePath, 'utf-8');
const htmlContent = placeholderContent.replace(
'<!-- CONTENT -->',
'Looks like the GUI app has not yet been compiled.<br /> ' +
'Run <code>yarn build</code> to continue, then restart the server.'
);
res.status(500).send(htmlContent);
});
} else { // GUI enabled, and build files present, let's go!!
app.use(express.static(guiPath));
}
app.use((req, res, next) => {
res.status(404).sendFile(path.join(__dirname, 'public', 'error.html'));
});
// Print nice welcome message to user
const printMessage = () => {
console.log(
`\x1b[36m\n` +
' __ __ _ ___ _ _ \n' +
' \\ \\ / /__| |__ ___ / __| |_ ___ __| |__\n' +
' \\ \\/\\/ / -_) \'_ \\___| (__| \' \\/ -_) _| / /\n' +
' \\_/\\_/\\___|_.__/ \\___|_||_\\___\\__|_\\_\\\n' +
`\x1b[0m\n`,
`\x1b[1m\x1b[32m🚀 Web-Check is up and running at http://localhost:${port} \x1b[0m\n\n`,
`\x1b[2m\x1b[36m🛟 For documentation and support, visit the GitHub repo: ` +
`https://github.com/lissy93/web-check \n`,
`💖 Found Web-Check useful? Consider sponsoring us on GitHub ` +
`to help fund maintenance & development.\x1b[0m`
);
};
// Create server
app.listen(port, () => {
printMessage();
});