fastify-simple-form

fastify-simple-form

Fastify plugin that adds content type parser for the application/x-www-form-urlencoded and/or multipart/form-data types.

Description

Essentially a tiny wrapper around busboy, that parses application/x-www-form-urlencoded and/or multipart/form-data content types and attaches associated fields to request.body.

NB! This plugin does not handle files, these get simply discarded as described here.

Install

npm install fastify-simple-form

TypeScript

Although this package includes typings for the plugin itself, you must install ones for node.js and busboy manually:

npm install @types/node @types/busboy --save-dev

Usage & Options

Selectively enable content types to parse

fastify.register(require('fastify-simple-form'), {
  multipart: true,   // Enable parsing for `multipart/form-data`, default: true
  urlencoded: false, // Disable parsing for `application/x-www-form-urlencoded`, default: true
});

This plugin has no effect when both options above are set to false!

Options for busboy

Accepts identical options to those of busboy constructor (with the exception of headers, which will be omitted), e.g.:

fastify.register(require('fastify-simple-form'), {
  defCharset: 'utf8',
  limits: {
    fieldNameSize: 100, // Max field name size (in bytes), default: 100
    fieldSize: 1000000, // Max field value size (in bytes), default: 1MB
    fields: 10,         // Max number of non-file fields, default: Infinity
  },
});

Example

Given server & handler:

import Fastify from 'fastify';
import SimpleFormPlugin from 'fastify-simple-form';

const fastify = Fastify();

fastify.register(SimpleFormPlugin);

fastify.post(
  '/token',
  {
    schema: {
      body: {
        type: 'object',
        properties: {
          username: {
            type: 'string',
          },
          password: {
            type: 'string',
          },
          client_id: {
            type: 'string',
            format: 'uuid',
          },
          client_secret: {
            type: 'string',
          },
          refresh_token: {
            type: 'string',
            format: 'uuid',
          },
          grant_type: {
            type: 'string',
            enum: ['authorization_code', 'refresh_token'],
          },
        },
        required: ['grant_type'],
      },
    },
  },
  (request, reply) => {
    reply.send(request.body);
  },
);

fastify.listen(3000);

These requests would succeed:

curl \
  -F "client_id=e52b2864-7611-4f26-94e4-d13f7039f25d" \
  -F "client_secret=rGGb45-awp0Q9X2yP3CxwhP8HhUY8uW1" \
  -F "refresh_token=f5e6ca6e-e2cf-4130-9b3f-26727ca11f78" \
  -F "grant_type=refresh_token" \
  localhost:3000/token

curl \
  -d "client_id=e52b2864-7611-4f26-94e4-d13f7039f25d" \
  -d "client_secret=rGGb45-awp0Q9X2yP3CxwhP8HhUY8uW1" \
  -d "refresh_token=f5e6ca6e-e2cf-4130-9b3f-26727ca11f78" \
  -d "grant_type=refresh_token" \
  localhost:3000/token

Response:

{
  "client_id": "e52b2864-7611-4f26-94e4-d13f7039f25d",
  "client_secret": "rGGb45-awp0Q9X2yP3CxwhP8HhUY8uW1",
  "refresh_token": "f5e6ca6e-e2cf-4130-9b3f-26727ca11f78",
  "grant_type": "refresh_token"
}

While these won't pass the schema validation

curl \
  -F "username=jon" \
  -F "password=snow" \
  -F "grant_type=password" \
  localhost:3000/token

curl \
  -d "username=jon" \
  -d "password=snow" \
  -d "grant_type=password" \
  localhost:3000/token

Response

{
  "statusCode": 400,
  "error": "Bad Request",
  "message": "body.grant_type should be equal to one of the allowed values"
}