@forrestjs/service-fastify

ForrestJS service which helps setting up an FastifyJS server.

DEMO:
https://codesandbox.io/s/service-fastify-th8dq

Install & Setup

npm add @forrestjs/service-fastify

Set it up in your FastifyJS App:

// index.js
const forrestjs = require('@forrestjs/core');
const fastifyService = require('@forrestjs/service-fastify');

// Create an Home Page for the Web App
const homePage = () => ({
  target: '$FASTIFY_ROUTE',
  handler: [
    {
      method: 'GET',
      url: '/',
      handler: async () => `Hello World`,
    },
  ],
});

// Run the App:
forrestjs.run({
  settings: {
    fastify: {
      port: 8080,
    },
  },
  services: [fastifyService],
  features: [homePage],
});

---

Configuration & Environment

📝 fastify.port

Sets up the port on which the server will listen for requests.

It falls back to environment variables:

• process.env.REACT_APP_PORT
• process.env.PORT
• 8080 (default value)

📝 fastify.instance.options

Let you pass arbitrary configuration to the Fastify instance.

📝 fastify.tdd.scope

Let you setup the root of the testing APIs.

Default: /test

---

Context

The ForrestJS App will be decorated with:

🌎 fastify

A reference to the Fastify instance as configured during the booting of the App. It allows to fully manipulate the running server.

const fastify = getContext('fastify');

🌎 axios

A reference to the static instance of Axios.

const axios = getContext('axios');
await axios.get('/');

---

Testing Support

Service Fastify ships testing facilities with the goal of making end-2-end testing easy for you.

The idea is to let the testing enviornment interact with the Fastify instance using REST APIs that are available exclusively whith process.env.NODE_ENV set to:

• development
• test

🔥 You must also pass the environmental variable 🔥

DANGEROUSLY_ENABLE_FASTIFY_TDD_ENDPOINT=yes

Those test-specific APIs are exposed under a /test/... root that you can change by setting fastify.tdd.root.

Test Healthcheck

The root Route /test acts as healthcheck for running tests. Any test client should await for a 200 reply from this endpoint before attempting to run any call.

By default there is no logic to this healthcheck, but you can interact with by implementing two extensions:

• $FASTIFY_TDD_CHECK
• $FASTIFY_TDD_ROOT

Test APIs

get://test/reset

Runs the $FASTIFY_TDD_RESET handlers to reset the App's state.

get://test/config?key=foobar&value=123

Reads a configuration value from the App

post://test/config { key: 'foobar', value: 555 }

Writes a configuration value into the App

post://test/axios/stubs

delete://test/axios/stubs

---

Extensions

All the extensions exposed by service-fastify are synchronous and executes in serie.

🧩 $FASTIFY_OPTIONS

It allows to programmatically modify the options that are given to the Fastify's instance, it works in waterfall.

registerAction({
  target: '$FASTIFY_OPTIONS',
  handler: (defaultOptions) => ({
    ...defaultOptions,
    logger: true,
  }),
});

🧩 $FASTIFY_HACKS_BEFORE

This hook fires before any other step.
It receives a direct reference to the fastify instance.

registerAction({
  target: '$FASTIFY_HACKS_BEFORE',
  handler: ({ fastify }) => {
    // Do something with the Fastify's instance
    fastify.register();
  },
});

🧩 $FASTIFY_HACKS_AFTER

This hook fires after any other step.
It receives a direct reference to the fastify instance.

registerAction({
  target: '$FASTIFY_HACKS_AFTER',
  handler: ({ fastify }) => {
    // Do something with the Fastify's instance
    fastify.register();
  },
});

🧩 $FASTIFY_PLUGIN

Let register Fastify plugins or decorate the instance.

registerAction({
  hook: '$FASTIFY_PLUGIN',
  handler: ({ registerPlugin }) => {
    registerPlugin(/* fastify plugin */);
    registerPlugin(/* fastify plugin */);
  },
});

It also receives API for decorating the Fastify instance:

registerAction({
  hook: '$FASTIFY_PLUGIN',
  handler: ({ decorateRequest }) => {
    const user = { name: 'Marco' };
    decorateRequest('user', user);
  },
});

🧩 $FASTIFY_ROUTE

Lets implement first level routes in your Fastify instance:

// With the API:
registerAction({
  target: '$FASTIFY_ROUTE',
  handler: ({ registerRoute }) =>
    registerRoute({
      method: 'GET',
      url: '/',
      handler: (req, res) => res.send('Hello World'),
    }),
});

// With direct values:
registerAction({
  target: '$FASTIFY_ROUTE',
  handler: () => ({
    method: 'GET',
    url: '/',
    handler: (req, res) => res.send('Hello World'),
  }),
});

// With multiple routes
registerAction({
  target: '$FASTIFY_ROUTE',
  handler: () => [
    {
      method: 'GET',
      url: '/p1',
      handler: (req, res) => res.send('Page1'),
    },
    {
      method: 'GET',
      url: '/p2',
      handler: (req, res) => res.send('Page2'),
    },
  ],
});

🧩 $FASTIFY_TDD_RESET

Let you inject state reset logic from any Service or Feature.

Tests will then call /test/reset in order to trigger an App's state reset.

registerAction({
  target: '$FASTIFY_TDD_CHECK',
  handler: ({ registerTddReset }) => {
    registerTddCheck(async ({ getContext }) => {
      const pg = getContext('pg');
      return pg.query('DROP SCHEMA "public" CASCADE');
    });
  },
});

🧩 $FASTIFY_TDD_CHECK

Let you inject preHandlers to the /test route.

Use this to await for database connections or other preconditions.

registerAction({
  target: '$FASTIFY_TDD_CHECK',
  handler: ({ registerTddCheck }) => {
    // Middleware style
    registerTddCheck((request, reply, next) => {
      console.log('Healthcheck with callback');
      next();
    });

    // Async style
    registerTddCheck(async (request, reply) => {
      console.log('Asynchronous healthcheck');
    });
  },
});

🧩 $FASTIFY_TDD_ROOT

Let you implement the returning body of the /test route.

registerAction({
  target: '$FASTIFY_TDD_ROOT',
  name: 'registerTddRoute',
  handler: () => (request, reply) => reply.send('ok'),
});

🧩 $FASTIFY_TDD_ROOT

Let you extend the /test API with custom sub-routes.

It works exactly as $FASTIFY_ROUTE, but all the routes you define are scoped with the testing prefix.