hapi-field-auth

Hapi server plugin for field-level authorization.

Tested with

• Node 14/16, Hapi 18/19/20, Joi 17
• Node 10, Hapi 18, Joi 16

Install

npm install hapi-field-auth

Purpose

This plugin provides field-level authorization (not authentication) for Hapi routes -- particularly useful for PATCH routes. If the request payload has fields with special constraints in respect to the scope of the authenticated user, this plugin allows restricting access on field-level and adding field validation depending on the scope.

A prerequisite is authentication. Use any authentication plugin, e.g., hapi-auth-basic or hapi-auth-bearer-token. The authentication plugin must properly set request.auth.credentials.scope with the authenticated user's scope for this plugin to work.

Dynamic scopes referring to the request object (query, params, payload, and credentials) are supported, e.g., user-{params.id}. Prefix characters ! and + are not (yet) supported.

Usage

Register the plugin with Hapi server like this:

const Hapi = require('@hapi/hapi');
const hapiAuthBasic = require('@hapi/basic');
const hapiFieldAuth = require('hapi-field-auth');

const server = new Hapi.Server({
  port: 3000,
});

const provision = async () => {
  await server.register([hapiAuthBasic, hapiFieldAuth]);
  // ...
  await server.start();
};

provision();

Your route configuration may look like this:

server.route({
  method: 'PATCH',
  path: '/example',
  options: {
    auth: {
      access: { // route-level auth -> HTTP 401/403
        scope: ['write', 'write.extended'], // multiple scopes on route-level
      },
    },
    validate: {
      payload: ExampleSchema, // Joi schema validation -> HTTP 400
    },
    plugins: {
      'hapi-field-auth': [{ // add field-level authorization -> HTTP 403
        fields: ['myProtectedField'], // request payload properties
        scope: ['write.extended'], // restricted scopes on field-level
      }, {
        fields: ['activeUntil', 'validUntil'],
        scope: ['write.extended'], // restricted scopes on field-level...
        validate: Joi.date().min('now').allow(null), // ...OR additional Joi schema -> HTTP 400
      }],
    },
  },
  handler: function (request, h) {
    // ...
  }
});