API Starter

A simple starter-kit for developing DARRT-style APIs. DARRT is an acronym which stands for Data, Actions, Resources, Representations, & Transitions. The DARRT library is used in the book "Design and Build Great Web APIs" (https://pragprog.com/book/maapis/design-and-build-great-web-apis).

Set up your project

First, FORK this repo (or just copy the /dartt/ folder and the root index.js and package.json files into your own project folder).

This project has a package.json which identifies the following runtime dependencies:

• body-parser
• cors
• ejs
• express

You can use npm install to update all dependencies. If you just copy the files, be sure to install/update the dependencies yourself.

Update the control files

The project SHOULD work "out-of-the-box" as a simple CRUD-style API to manage persons. To make this work for your own API needs, you only need to update the files in the /darrt/ folder. See the steps below for details.

The DARRT folder

The /darrt/ folder holds the framework base files:

• data.js
• actions.js
• resources.js
• representations.js
• transitions.js

These four files are the ones you'll edit to match your API needs.

The lib and representors folders

There are two subfolders, too: /darrt/lib and /darrt/representors/. The lib folder holds the operational support files for managing the information in your control files in the /darrt/ folder. The representors folder holds response representation templates (using ejs) matched to media-type strings. The representors in the base library are:

• application/json
• text/csv
• application/forms+json
• application/links+json (alpha)
• application/prag+sjon (beta)

You can edit these and add new representors for additional media types as needed.

The darrt/data.js file

This defines what state is passed back and forth

• properties (MUST include id, dateCreated, & dateUpdated; SHOULD include status)
• enums
• requireds
• defaults

The darrt/actions.js file

This implements the internal functionality your service supports through a series of exported functions. See the included actions.js for examples.

The darrt/resources.js file

This file contains the routes and calling routines for all the URLs in your API and maps to the actions. This is the classic express.js-style router.get(...), router.post(...) set of operations that call the exported actions.js methods via a special operation (utils.handler(...)). See the included resources.js for examples.

The representation.js file

This file contains the response representations your service supports. This is based on the representor pattern. See the darrt/representors/ folder for built-in examples of a handful of media-type representors.

The transitions.js file

This file contains all the links and forms your service API will emit at runtime. If you are only supporting application/json or text/csv or some other format that has no hypermedia support, you can ignore this step.

Data Storage

The current project just stores the passed state on disk in the /data/ folder. This is handled by the /darrt/lib/components.js and /darrt/lib/storage.js files. You can use this local storage approach or update it to use more robust storage tooling yourself and just modify the dependencies. NOTE that in this release, storage is implemented without support for Promises. A future version will make storage fully 'then-able' to make adding remote adpaters easy to do.

TODO

1. Convert if and switcH statements to polymorphic function paradigm, or
   "semantics-driven development".