typra

a type-safe express.js wrapper with validations. inspired by TRPC.

Why

Don't get me wrong, I love Express.js and it is a great library, it is simple yet powerful and it'd be perfect if it had type safety and validation by default. Well, no need anymore.

Installation

npm i typra zod

How to use

The library exposes init function that returns application object similar to calling express(). You can call it and start using it like you use express with only one difference.

The application object that's returned by init exposes to functions, input and listen the latter is self explanatory. input takes to arguments which are zod schemas, params and body schemas. In the case of non existent data or to ignore validation (eg: body of a get request) you can pass either z.object({}) or emit it like in the example below.

get, post, put, patch, delete functions are all exposed by input

import { init } from 'typra';
import { z } from 'zod';

const app = init();

app
  .input(
    z.object({
      id: z.coerce.number(),
    }),
  )
  .get('/user/:id', async (req, res) => {
    res.json({
      id: req.params.id, // IDE completion
    });
  });

app.listen(3000, () => {
  console.log('server is successfully running');
});

Note: if the field is supposed to be a number you have to always define the field as z.coerce.number(). Using z.number() will always make schema fail.