Building and Testing Rails JSON API with

RSpec

Eddie Lau (3dd13@42la.bs)23 Oct 2014

Agenda

• 1. Development Process

• 2. API Design

• 3. Rails, RSpec and Gems

• 4. Mini-hackathon

Mini-hackthonbuild your own API

Setup (Mac)Ruby \curl -sSL https://get.rvm.io | bash rvm install 2.1.3

Gems neededgem install bundlergem install rails

Sample project codegit clone http://github.com/3dd13/api_rspec_workshopcd api_rspec_workshopbundle install

1. Development Process

WorkflowInitial• UX / UI / Wireframe• Communication / Endpoint needed• API Design• Test cases• GREEN

Add feature• UX / UI / Wireframe• Communication / Endpoint needed• API Design• Upgrade version (if needed)• Add / Update test cases• GREEN

2. API Design

Architecture

Frontend Js Client

Backend Server

HTTP API

42 Labs Stack

AngularJS (Browser or Mobile)

Ruby on Rails / Node.js

RESTful API - JSON

42 Labs Stack

Customer Web(AngularJS)

Customer Mobile(AngularJS)

Admin Web

Ruby on Rails

HTML

JSON API

JSON API

RESTful• GET http://example.com/projects.json

• GET http://example.com/projects/:id.json

• PATCH http://example.com/projects/:id.json

body: {project: {name: “”, …}}

• POST http://example.com/projects.json

body: {project: {name: “”, …}}

• DELETE http://example.com/projects/:id.json

Standard / Convention

Always

GET, CREATE, UPDATE, DELETE resource

RESTful ?1. Search projects by date range

GET http://example.com/projects/search.json

2. Create multiple projects

POST http://example.com/projects.json

body: [{project: {name: “”, …}, {project: {name: “”,…}} ]

3. Update multiple projects (e.g. mark as archived)

PATCH http://example.com/projects/archive.json

body: { project_ids: [1, 3, 5]}

Suggestionnot always true !

1. Search projects by date range

GET http://example.com/projects.json?date_range_filter=last_week

2. Create multiple projects

POST http://example.com/project_batches.json

body: {project_batch: [{ project: {name: “”} }, …]}

3. Update multiple projects (e.g. mark as archived)

PATCH http://example.com/projects/1,3,5.json

RESTful Authentication

• Step 1: User Sign In

POST http://example.com/users/sessions

body: {email: “user@example.com”, password: “password”}

Response:

{session: {auth_token: “123abc456defxxxxx”}}

• Step 2: Access Protected Action

GET http://example.com/users/projects/1.json

Header: X-AUTH-TOKEN 123abc456defxxxxx

Versioning

• GET http://example.com/api/v1/projects.json

• GET http://example.com/api/projects.jsonAccept: application/vnd.charityspring.v1

3. Rails & RSpecand other gems

Testing

rspec

expect(status).to eq 201

expect(response_body).to be_json_eql(expected_json)

expect{ do_request }.to change{ Project.count }.from(0).to(1)

factory_girl

FactoryGirl.define do factory :user do sequence(:email) { |n| "user#{n}@example.com"} password "password" endend

user = FactoryGirl.create(:user)

rspec_api_documentation

rake docs:generate

4. Mini-hackthonbuild your own API

Setup (Mac)Ruby \curl -sSL https://get.rvm.io | bash rvm install 2.1.3

Gems neededgem install bundlergem install rails

Sample project codegit clone http://github.com/3dd13/api_rspec_workshopcd api_rspec_workshopbundle install

Run test cases

rake db:migrate

rake

rake docs:generate

Create seed data

rake db:seed

Code walk through

Note:

1. password is plain text

2. no database index was created

don’t use it in production, feel free to change the code

Start coding ~1. Visitor wants to see a list of crowd funding projects

2. Visitor wants to search crowd funding projects by name

3. Visitor wants to sign up using email and password

4. Visitor wants to sign in using email and password

5. Member wants to create a crowd funding project

6. Member wants to see a list of crowd funding project she created

7. Member wants to pledge a crowd funding project

8. Member wants to see a list of crowd funding project she pledged

Advanced

1. Member wants to pledge and pay via Paypal / Stripe

2. Add a new API endpoint to v2