Megalo

Deno HTTP server framework aiming for maximum speed

Example

// server.ts
import { Megalo, Controller } from 'https://deno.land/x/megalo/mod.ts';
import { cors } from '[./plugins/cors.ts](https://deno.land/x/megalo/plugins/cors.ts)';


const megalo = new Megalo({
    // optionally add a notFoundHandler
    notFoundHandler: (req, res) => res.status(404).body(`${req.pathname} not found :(`),
    // optionally add an errorHandler
    errorHandler: (_err, _req, res, httpErr) => {
        // if NotFoundError, etc. was thrown
        if (httpErr) return res.status(httpErr.status).body(httpErr.message);
        res.status(500).body('Internal Server Error');
    },
    plugins: [cors({ origin: 'http://127.0.0.1:9000' })],
});

megalo
    .get('/', { parseQuery: false }, (_req, res) => {
        res.body('hello megalo!', {
            status: 200,
            headers: { ['Content-Type']: 'text/html' },
        });
    })
    .post('/', (_req, res) => {
        res.body('Secret handler', { status: 200 });
    })
    .get('/sus', (_req, res) => {
        res.body('sus page', {
            status: 200,
            headers: { ['Content-Type']: 'text/html' },
        });
    })
    .get(/^\/regex(\/.*)?$/, (_req, res) => res.body(undefined, { status: 200 }))
    .get('/pattern/:id', ({ params }, res) => {
        res.body(`id: ${params.id}`, {
            status: 200,
            headers: { ['Content-Type']: 'text/html' },
        });
    })
    .post('/posted', (_req, res) => {
        res.body('you posted it :)', { status: 200 });
    })
    .controller(
        new Controller('/users')
            .get('/', (_req, res) => res.body('user', { status: 200 }))
            .get('/:id', (req, res) => res.body(`user id: ${req.params.id}`, { status: 200 }))
    );

console.log(`Startup time: ${performance.now()}ms`);
megalo.listen({ port: 9000, hostname: '127.0.0.1' });

Start Server

Use --allow-hrtime for more precise performance.now()

deno run --allow-net --allow-hrtime --unstable server.ts

Route resolution

Routes are resolved in this order

string literal ex. "/sus"
controllers ex. new Controller("/users")
patterns ex. "/users/:id"
regex ex. /^.*\/regex\/.*\/?$/
wildcard (You can only have one of these per method) "*"
notFoundHandler

Hooks

You can use hooks to run functions when certain lifecycle events occur. Hooks can be used on the Megalo instance or Controller instance.

preRoute: runs before pathname is evaluated and handler is chosen
preHandle: runs directly before handler
postHandle: runs directly after handler (may change in the future)

The megalo instance has some exclusive hooks

preParse: runs before anything is done, right when request is received
preSend: run directly before response is sent to client, last chance to add headers or whatever

This is an example on how to use hooks. If you return the res from the hook it will be sent early

import { Megalo, InternalServerError } from 'https://deno.land/x/megalo/mod.ts';

const megalo = new Megalo();

megalo.addHook((req, res) => {}).get((req, res) => {
    throw new InternalServerError({ message: 'uh oh' });
    res.status(200);
});

megalo.listen({ port: 9000, hostname: '127.0.0.1' });

Error Throwing

You can throw special exported errors to have the response status and body automatically set.

import { Megalo, InternalServerError } from 'https://deno.land/x/megalo/mod.ts';

const megalo = new Megalo();

megalo.get((req) => {
    throw new InternalServerError({ message: 'uh oh' });
    res.status(200);
});

megalo.listen({ port: 9000, hostname: '127.0.0.1' });

Notes

If using serve / flash instead of listen, until https://github.com/denoland/deno/issues/15813 is resolved, in all POST, PUT, and PATCH routes you MUST await the body or else deno will panic. Also, do not use this in production as any POST, PUT, or PATCH request will crash the server, until this bug is fixed.