toisu-body

Body parsing middleware for Toisu!

This module is a thin wrapper around the excellent body module. It appends a 'body' field to the context of your request-response chain.

Example

This server will send back JSON sent to it.

import http from 'http';
import Toisu from '@toisu/toisu';
import * as body from '@toisu/body';

const app = new Toisu();

app.use(body.json()); // Note, non-json requests will lead to an error!

app.use(function (req, res) {
  const body = this.get('body');
  const stringified = JSON.stringify(body);

  res.writeHead(200, {
    'Content-Type': 'application/json',
    'Content-Length': Buffer.byteLength(stringified)
  });

  res.write(stringified);
  res.end();
});

http.createServer(app.requestHandler).listen(3000);

Handling errors

If clients can send requests which aren't, for example, JSON, then JSON middleware will reject with an error when it attempts to parse the body. There are a few solutions to this issue:

• Handle it in the errorHandler property of the app object.
• Use the text middleware and parse it by hand.
• Chain the middleware with a catch.

I recommend the third solution, which looks like:

import http from 'http';
import Toisu from '@toisu/toisu';
import * as body from '@toisu/body';

const app = new Toisu();
const json = body.json();

app.use(function (req, res) {
  return json.call(this, req, res).catch(function (err) {
    res.statusCode = 400;
    res.end();
  });
});

app.use(function (req, res) {
  const body = this.get('body');
  const stringified = JSON.stringify(body);

  res.writeHead(200, {
    'Content-Type': 'application/json',
    'Content-Length': Buffer.byteLength(stringified)
  });

  res.write(stringified);
  res.end();
});

http.createServer(app.requestHandler).listen(3000);

You could go further and check the content type of the request as well, and if the content type isn't compatible with JSON use a 415 status code.

API

This module exports four methods. Each takes a single options object which is passed on to the body module internally. See the documentation for that module for details on the options available. Each method returns a Toisu! middeware function.

text(options)

Gets the body from the request as a string, and attempts no parsing on it. Useful for when you need to do some custom checks or parsing. It appends this string to the Toisu! request-response context (this in middlewares) as 'body'.

json(options)

Gets the body from the request and parses it as JSON. It appends this string to the Toisu! request-response context (this in middlewares) as 'body'.

form(options)

Gets the body from the request and parses it as a form. It appends this string to the Toisu! request-response context (this in middlewares) as 'body'.

any(options)

Looks at the Content-Type header and will parse as either form data or JSON. If the content type doesn't conform to either, it will throw an error.