Phase 3 Project Guidelines

Learning Goals

• Build a web basic API with Sinatra and Active Record to support a React frontend

Introduction

Congrats on getting through all the material for Phase 3! Now's the time to put it all together and build something from scratch to reinforce what you know and expand your horizons.

The focus of this project is building a Sinatra API backend that uses Active Record to access and persist data in a database, which will be used by a separate React frontend that interacts with the database via the API.

Requirements

For this project, you must:

• Use Active Record to interact with a database.
• Have at least two models with a one-to-many relationship.
• At a minimum, set up the following API routes in Sinatra:
  • create and read actions for both models
  • full CRUD capability for one of the models: The update action should be implemented using a form that is pre-filled with existing values for the object. On submission of the form, the object should update. Note: Using a like button or similar will not meet the update requirement.
• Build a separate React frontend application that interacts with the API to perform CRUD actions.
• Implement proper front end state management. You should be updating state using a setState function after receiving your response from a POST, PATCH, or DELETE request. You should NOT be relying on a GET request to update state.
• Use good OO design patterns. You should have separate classes for each of your models, and create instance and class methods as necessary.
• Routes in your application (both client side and back end) should follow RESTful conventions.
• Use your back end optimally. Pass JSON for related associations to the front end from the back end. You should use active record methods in your controller to grab the needed data from your database and provide as JSON to the front end. You should NOT be relying on filtering front end state or a separate fetch request to retrieve related data.

For example, build a todo list application with a React frontend interface and a Sinatra backend API, where a user can:

• Create a new todo
• Read a list of all todos
• Update an individual todo
• Delete a todo

A Todo can be tagged with a Category, so that each todo belongs to a category and each category has many todos.

Getting Started

Backend Setup

This repository has all the starter code needed to get a Sinatra backend up and running. Fork and clone this repository to get started. Then, run bundle install to install the gems.

Important: Be sure you fork a copy of the repo into your GitHub account before cloning it. You can do this by using the link above or by clicking the "Octocat" button at the top of this page, then clicking "Fork" in the upper right corner of the repo page.

The app/controllers/application_controller.rb file has an example GET route handler. Replace this route with routes for your project.

You can start your server with:

$ bundle exec rake server

This will run your server on port http://localhost:9292.

Frontend Setup

Your backend and your frontend should be in two different repositories.

Create a new repository in a separate folder with a React app for your frontend. To do this, cd out of the backend project directory, and use create-react-app to generate the necessary code for your React frontend:

$ npx create-react-app my-app-frontend

After creating the project locally, you should also create a repository on GitHub to host your repo and help collaborate, if you're working with a partner.

Fetch Example

Your React app should make fetch requests to your Sinatra backend! Here's an example:

fetch("http://localhost:9292/test")
  .then((r) => r.json())
  .then((data) => console.log(data));

Project Tips

• This project is intended to focus more on the backend than the frontend, so try and keep the React side of things relatively simple. Focus on working with Active Record and performing CRUD actions. What are some interesting queries you can write? What kinds of questions can you ask of your data?
• Once you have a project idea, come up with a domain model and decide what relationships exist between the models in your application. Use a tool like dbdiagram.io to help visualize your models.
• Decide on your API endpoints. What data should they return? What kind of CRUD action should they perform? What data do they need from the client?
• Use Postman to test your endpoints.
• Use binding.pry to debug your requests on the server. It's very helpful to use a binding.pry in your controller within a route to see what params are being sent.
• Use the Network Tab in the Dev Tools in the frontend to debug your requests.

Resources

• create-react-app
• dbdiagram.io
• Postman