Beginner's Guide to Ruby API Consumption

Understanding Ruby API Consumption

Consuming an API (Application Programming Interface) in Ruby involves making HTTP requests to retrieve or send data. The most common way to work with APIs in Ruby is by using the Net::HTTP library or the popular HTTParty gem. Below are some practical examples for both methods.

Example 1: Using Net::HTTP

Making a GET Request

require 'net/http'
require 'json'

url = URI.parse('https://api.example.com/data')
response = Net::HTTP.get_response(url)

if response.is_a?(Net::HTTPSuccess)
  data = JSON.parse(response.body)
  puts data
else
  puts "Error: #{response.code} - #{response.message}"
end

Explanation:

• require ’net/http’: Loads the Net::HTTP library for making HTTP requests.
• require ‘json’: Loads the JSON library for parsing JSON data.
• URI.parse: Parses the URL string into a URI object.
• Net::HTTP.get_response: Sends a GET request to the specified URL.
• JSON.parse: Converts the JSON response body into a Ruby hash.

Example 2: Using the HTTParty Gem

Installing HTTParty

To use HTTParty, you first need to install the gem. Add it to your Gemfile or install it directly:

gem install httparty

Making a GET Request

require 'httparty'

response = HTTParty.get('https://api.example.com/data')

if response.success?
  data = response.parsed_response
  puts data
else
  puts "Error: #{response.code} - #{response.message}"
end

Explanation:

• require ‘httparty’: Loads the HTTParty library.
• HTTParty.get: Sends a GET request to the specified URL.
• response.success?: Checks if the response is successful.
• response.parsed_response: Automatically parses the JSON response into a Ruby hash.

Example 3: Sending Data with a POST Request

Using Net::HTTP

require 'net/http'
require 'json'

url = URI.parse('https://api.example.com/data')
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true # Enable SSL if required

request = Net::HTTP::Post.new(url)
request.content_type = 'application/json'
request.body = JSON.dump({ key: 'value' })

response = http.request(request)

if response.is_a?(Net::HTTPSuccess)
  puts "Data sent successfully!"
else
  puts "Error: #{response.code} - #{response.message}"
end

Explanation:

• Net::HTTP.new: Creates a new HTTP instance for requests.
• http.use_ssl = true: Enables SSL for secure requests.
• Net::HTTP::Post.new: Prepares a POST request.
• request.content_type: Sets the content type to JSON.
• JSON.dump: Converts a Ruby hash into a JSON string.

Conclusion

In this guide, we covered how to consume APIs in Ruby using both the Net::HTTP library and the HTTParty gem. With these examples, you should be able to make GET and POST requests, as well as handle responses and parse JSON data effectively. Happy coding!