Making GET Requests and Handling Responses

Welcome to the second lesson in our journey of interacting with APIs in Ruby. In the previous lesson, we laid a strong foundation by understanding RESTful APIs and how HTTP requests facilitate interactions with them. We used curl to manually craft and send a GET request to an endpoint. Now, we are transitioning to automating this process using Ruby. This lesson introduces Ruby's Net::HTTP library, which allows us to send HTTP requests effortlessly in our scripts, making it an invaluable tool in the realm of web development and API integration.

To make HTTP requests in Ruby, we use the Net::HTTP library, a built-in library for handling HTTP requests. This means you don't need to install any additional gems to start making HTTP requests.

When interacting with an API, it's helpful to define a base URL for the service you're communicating with. This makes your code more modular and easy to maintain, allowing you to change the root of your API URL in one place without modifying each request.

# Base URL for the API
base_url = "http://localhost:8000"

By setting this base URL, we can easily concatenate endpoints for different services within the API, making our code cleaner and more adaptable.

Let's dive into the process of fetching data from an API using Ruby's Net::HTTP library. Our goal is to retrieve a list of to-do items from the /todos endpoint using the GET method.

require 'net/http'
require 'uri'

# Construct the full URL
uri = URI("#{base_url}/todos")

# Perform the GET request
response = Net::HTTP.get_response(uri)

# Print raw response
puts "Raw Response:"
puts response.body

By using Net::HTTP.get_response, we send a GET request to the constructed full URL. The response from the server, stored in the variable response, is then printed using response.body, which gives us the raw response body as a string.

Here’s an example of what the raw response might look like:

Raw Response:
[
  {
    "description": "Milk, eggs, bread, and coffee",
    "done": false,
    "id": 1,
    "title": "Buy groceries"
  },
  {
    "description": "Check in and catch up",
    "done": true,
    "id": 2,
    "title": "Call mom"
  },
  {
    "description": "Summarize Q4 performance metrics",
    "done": false,
    "id": 3,
    "title": "Finish project report"
  },
  {
    "description": "30 minutes of cardio",
    "done": true,
    "id": 4,
    "title": "Workout"
  }
]

This raw output allows us to see the immediate result returned by the server, serving as a starting point for further processing of the data.