Comparing authentication methods in API with Ruby on Rails - Part 1

In this post, we will compare the most common authentication methods in API with Ruby on Rails.

I. Introduction

When building an API, one of the most important things to consider is how to authenticate users. There are many different methods for authenticating users in an API, each with its own advantages and disadvantages. In this post, we will compare the most common authentication methods in API with Ruby on Rails. These methods include:

Basic authentication: The user sends their username and password with each request.
Token base authentication: The user sends a token with each request instead of their username and password.
OAuth authentication: The user authorizes a third-party application to access their data on their behalf.
JWT authentication: The user sends a JSON Web Token (JWT) with each request instead of their username and password.
Session authentication: The user logs in with their username and password, and the server creates a session to track the user’s authentication status.
API key authentication: The user sends an API key with each request to authenticate themselves.

II. Basic authentication

Basic authentication is the simplest form of authentication in an API. The user sends their username and password with each request, and the server checks the credentials against a database of users. If the credentials are valid, the server allows the user to access the requested resource.

The main advantage of basic authentication is that it is easy to implement and understand. However, it is not very secure, as the username and password are sent in plain text with each request. This makes it vulnerable

Example of basic authentication in Ruby on Rails:

class ApplicationController < ActionController::API
  http_basic_authenticate_with name: "admin", password: "password"
end

Advantages of basic authentication:

Easy to implement and understand.
Works with any HTTP client.
No need to store session data on the server.

Disadvantages of basic authentication:

Not very secure, as the username and password are sent in plain text with each request.
Not suitable for high-security applications.
Vulner.

Common use cases for basic authentication:

Simple authentication requirements that do not require user-specific data.
Internal APIs that do not need to be exposed to the public.
Prototyping and testing.

Best practices for basic authentication:

Use HTTPS to encrypt the username and password in transit. By using HTTPS, you can encrypt the username and password in transit to prevent them from being intercepted by attackers. This is especially important if you are using basic authentication over an unsecured network, such as a public Wi-Fi network.
Use strong passwords. To prevent brute-force attacks, you should use strong passwords that are difficult to guess or brute-force. You can use password policies to enforce password complexity requirements, such as minimum length, uppercase and lowercase letters, numbers, and special characters.
Use rate limiting. To prevent brute-force attacks, you can use rate limiting to limit the number of login attempts per user or IP address. If a user exceeds the login attempts, you can temporarily block the user or IP address to prevent further attempts.
Use secure cookies. If you are using basic authentication with a web application, you can use secure cookies to store the user’s authentication status. Secure cookies are encrypted and can only be accessed over HTTPS, making them more secure than plain text cookies.

III. OAuth authentication

OAuth authentication is a protocol that allows a user to authorize a third-party application to access their data on their behalf. The user logs in with their username and password, and the server generates an access token that the third-party application can use to access the user’s data.

The main advantage of OAuth authentication is that it allows users to grant access to their data without sharing their username and password with the third-party application. However, it can be more complex to implement, as the server needs to handle the OAuth flow and manage access tokens.

In Ruby on Rails, you can use the omniauth gem to implement OAuth authentication:

# Gemfile

gem 'omniauth'

# config/initializers/omniauth.rb

Rails.application.config.middleware.use OmniAuth::Builder do
  provider :facebook, ENV['FACEBOOK_APP_ID'], ENV['FACEBOOK_APP_SECRET']
end

Advantages of OAuth authentication:

Allows users to grant access to their data without sharing their username and password.
Works with any HTTP client.
No need to store session data on the server.

Disadvantages of OAuth authentication:

More complex to implement than basic authentication.
The server needs to handle the OAuth flow and manage access tokens.
Requires users to authorize third-party applications to access their data.

Common use cases for OAuth authentication:

Web applications that need to access user data from third-party applications.
Single sign-on (SSO) across multiple applications.
Securely sharing data between different services.

IV. Token base authentication

Token base authentication is a more secure alternative to basic authentication. Instead of sending their username and password with each request, the user sends a token that is generated by the server when they log in. The server checks the token against a database of valid tokens, and if the token is valid, the server allows the user to access the requested resource.

The main advantage of token base authentication is that it is more secure than basic authentication, as the token is not sent in plain text with each request. However, it can be more complex to implement, as the server needs to generate and manage tokens for each user.

These are many ways to implement token base authentication in Ruby on Rails:

Self-Contained Tokens (JWT -JSON Web Tokens): You can use the jwt gem to generate and verify JWTs in Ruby on Rails. JWTs are stateless tokens that are signed with a secret key, making them difficult to tamper with or forge. Here is an example of token base authentication using the jwt

Example of token base authentication using JWT in Ruby on Rails:

class ApplicationController < ActionController::API
  before_action :authenticate_user!

  private

  def authenticate_user!
    token = request.headers["Authorization"]
    decoded_token = JWT.decode(token, Rails.application.secrets.secret_key_base)
    user_id = decoded_token.first["user_id"]
    user = User.find(user_id)
    head :unauthorized unless user
  end
end

class SessionsController < ApplicationController
  def create
    user = User.find_by(email: params[:email])
    if user&.authenticate(params[:password])
      token = JWT.encode({ user_id: user.id }, Rails.application.secrets.secret_key_base)
      render json: { token: token }
    else
      render json: { message: "Invalid email or password" }, status: :unauthorized
    end
  end
end

Opaque Tokens: You can use opaque tokens that are stored in a database and checked against a database of valid tokens. Opaque tokens are more secure than JWTs, as they are not easily decoded by attackers.

Example of token base authentication using opaque tokens in Ruby on Rails:

class ApplicationController < ActionController::API
  before_action :authenticate_user!

  private

  def authenticate_user!
    token = request.headers["Authorization"]
    user = User.find_by(token: token)
    head :unauthorized unless user
  end
end

class SessionsController < ApplicationController
  def create
    user = User.find_by(email: params[:email])
    if user&.authenticate(params[:password])
      token = SecureRandom.hex
      user.update(token: token)
      render json: { token: token }
    else
      render json: { message: "Invalid email or password" }, status: :unauthorized
    end
  end
end

Reference Tokens: You can use reference tokens that are stored in a database and checked against a database of valid tokens. Reference tokens are more secure than JWTs, as they are not easily decoded by attackers. Different from opaque tokens, reference tokens are not sent with each request, but are used to look up the user’s authentication status on the server.

Example of token base authentication using reference tokens in Ruby on Rails:

class ApplicationController < ActionController::API
  before_action :authenticate_user!

  private

  def authenticate_user!
    token = request.headers["Authorization"]
    user_id = Rails.cache.read(token)
    user = User.find(user_id)
    head :unauthorized unless user
  end
end

class SessionsController < ApplicationController
  def create
    user = User.find_by(email: params[:email])
    if user&.authenticate(params[:password])
      token = SecureRandom.hex
      Rails.cache.write(token, user.id)
      render json: { token: token }
    else
      render json: { message: "Invalid email or password" }, status: :unauthorized
    end
  end
end

Advantages of token base authentication:

More secure than basic authentication, as the token is not sent in plain text with each request.
Works with any HTTP client.
No need to store session data on the server.

Disadvantages of token base authentication:

More complex to implement than basic authentication.
The server needs to generate and manage tokens for each user.
Tokens can be stolen or compromised if not properly secured.

Common use cases for token base authentication:

APIs that require user-specific data and need to authenticate users securely.
Single sign-on (SSO) across multiple applications.
Securely sharing data between different services.

Best practices for token base authentication:

Use HTTPS to encrypt the token in transit. By using HTTPS, you can encrypt the token in transit to prevent it from being intercepted by attackers. This is especially important if you are using token base authentication over an unsecured network, such as a public Wi-Fi network.
Use short-lived tokens. To reduce the risk of token theft, you can use short-lived tokens that automatically expire after a certain period. You can set an expiration time for the tokens to automatically expire after a certain period, such as 15 minutes or 1 hour.
Use secure tokens. To prevent token theft, you should use secure tokens that are difficult to guess or brute-force. You can use random tokens that are long and complex to prevent them from being easily guessed or brute-forced.
Use token revocation. To prevent token theft, you can revoke tokens that have been stolen or compromised. If a token is stolen or compromised, you can invalidate the token on the server to prevent it from being used to access the user’s account.

V. JWT authentication

JWT authentication is a stateless authentication method that uses JSON Web Tokens (JWTs) to authenticate users. The user sends a JWT with each request, and the server verifies the JWT to authenticate the user.

The main advantage of JWT authentication is that it is stateless, meaning that the server does not need to store session data for each user. However, it can be more complex to implement, as the server needs to generate and verify JWTs for each user.

Example of JWT authentication in Ruby on Rails:

class ApplicationController < ActionController::API
  before_action :authenticate_user!

  private

  def authenticate_user!
    token = request.headers["Authorization"]
    decoded_token = JWT.decode(token, Rails.application.secrets.secret_key_base)
    user_id = decoded_token.first["user_id"]
    user = User.find(user_id)
    head :unauthorized unless user
  end
end

Advantages of JWT authentication:

Stateless, meaning that the server does not need to store session data for each user.
Works with any HTTP client.
No need to store session data on the server.

Disadvantages of JWT authentication:

More complex to implement than basic authentication.
The server needs to generate and verify JWTs for each user.
Tokens can be stolen or compromised if not properly secured. A JWT can be decoded by anyone who has the secret key used to sign the token.

Common use cases for JWT authentication:

Single sign-on (SSO) across multiple applications.
Stateless authentication for APIs.
Securely sharing data between different services. By using JWTs, you can securely share data between different services without the need for a centralized authentication server, as long as all services have access to the same secret key used to sign the JWTs.

Best practices for JWT authentication:

Use a secure secret key to sign the JWTs. The secret key should be long and random to prevent it from being easily guessed or brute-forced.
Use HTTPS to encrypt the JWTs in transit.
Use short-lived JWTs to reduce the risk of token theft. You can set an expiration time for the JWTs to automatically expire after a certain period.
Use JWTs to store only non-sensitive data. Avoid storing sensitive data such as passwords or credit card numbers in the JWT payload, as the payload can be easily decoded by anyone who has the secret key used to sign the token.

VI. Session authentication

Session authentication is a stateful authentication method that uses sessions to authenticate users. The user logs in with their username and password, and the server creates a session to track the user’s authentication status.

The main advantage of session authentication is that it is easy to implement and understand. However, it can be less secure than other authentication methods, as the server needs to store session data for each user.

Example of session authentication in Ruby on Rails:

class SessionsController < ApplicationController
  def create
    user = User.find_by(email: params[:email])
    if user&.authenticate(params[:password])
      session[:user_id] = user.id
      render json: { message: "Logged in successfully" }
    else
      render json: { message: "Invalid email or password" }, status: :unauthorized
    end
  end
end

Advantages of session authentication:

Easy to implement and understand.
Works with any HTTP client.
No need to store session data on the server.

Disadvantages of session authentication:

Less secure than other authentication methods, as the server needs to store session data for each user.
Vulnerable to attacks such as session hijacking. If an attacker steals a user’s session ID, they can impersonate the user and access their account. To prevent session hijacking, you can use secure cookies and set the secure and httponly flags to prevent the session ID from being accessed by JavaScript. You can also use CSRF tokens to prevent cross-site request forgery attacks. CSRF tokens are unique tokens that are generated for each session and included in each request to verify that the request is coming from the user’s browser. If the CSRF token is missing or invalid, the server rejects the request.
Not suitable for high-security applications.

Common use cases for session authentication:

Web applications that need to track the user’s authentication status.
User-specific data that requires authentication.
E-commerce applications that need to track the user’s shopping cart and order history.

Best practices for session authentication:

Use secure cookies to store the session ID. Secure cookies are encrypted and can only be accessed over HTTPS, making them more secure than plain text cookies. You can set the secure and httponly flags to prevent the session ID from being accessed by JavaScript.
Use CSRF tokens to prevent cross-site request forgery attacks. CSRF tokens are unique tokens that are generated for each session and included in each request to verify that the request is coming from the user’s browser. If the CSRF token is missing or invalid, the server rejects the request.
Use rate limiting to prevent brute-force attacks. To prevent brute-force attacks, you can use rate limiting to limit the number of login attempts per user or IP address. If a user exceeds the login attempts, you can temporarily block the user or IP address to prevent further attempts.
Use strong passwords. To prevent brute-force attacks, you should use strong passwords that are difficult to guess or brute-force. You can use password policies to enforce password complexity requirements, such as minimum length, uppercase and lowercase letters, numbers, and special characters.
Use HTTPS to encrypt the session ID in transit. By using HTTPS, you can encrypt the session ID in transit to prevent it from being intercepted by attackers. This is especially important if you are using session authentication over an unsecured network, such as a public Wi-Fi network.
Use session expiration to automatically log out inactive users. To prevent session hijacking, you can set an expiration time for the session to automatically log out inactive users after a certain period. You can set the expiration time to a short period, such as 15 minutes or 1 hour, to reduce the risk of session hijacking.
Use secure cookies to store the user’s authentication status. Secure cookies are encrypted and can only be accessed over HTTPS, making them more secure than plain text cookies. You can set the secure and httponly flags to prevent the session ID from being accessed by JavaScript.
Use session revocation to invalidate stolen or compromised sessions. If a session is stolen or compromised, you can invalidate the session on the server to prevent it from being used to access the user’s account.
Use multi-factor authentication to add an extra layer of security. Multi-factor authentication requires users to provide two or more factors to authenticate, such as a password and a one-time code sent to their phone. By using multi-factor authentication, you can add an extra layer of security to prevent unauthorized access to the user’s account.

VII. API key authentication

API key authentication is a simple authentication method that uses API keys to authenticate users. The user sends an API key with each request, and the server checks the API key against a database of valid keys.

The main advantage of API key authentication is that it is easy to implement and understand. However, it can be less secure than other authentication methods, as the API key is sent in plain text with each request.

Example of API key authentication in Ruby on Rails:


class ApplicationController < ActionController::API
  before_action :authenticate_user!

  private

  def authenticate_user!
    api_key = request.headers["X-API-KEY"]
    user = User.find_by(api_key: api_key)
    head :unauthorized unless user
  end
end

Advantages of API key authentication:

Easy to implement and understand.
Works with any HTTP client.
No need to store session data on the server.

Disadvantages of API key authentication:

Less secure than other authentication methods, as the API key is sent in plain text with each request.
Vulnerable to attacks. If an attacker intercepts the API key, they can impersonate the user and access their account. To prevent API key theft, you can use HTTPS to encrypt the API key in transit. You can also rotate the API key periodically to reduce the risk of theft.
Not suitable for high-security applications.
Can be difficult to manage if you have a large number of users or API keys.
Not suitable for user-specific data. API key authentication is more suitable for simple authentication requirements that do not require user-specific data. If you need to authenticate users and access user-specific data, you should use token base authentication or JWT authentication instead.

Common use cases for API key authentication:

Simple authentication requirements that do not require user-specific data.
Internal APIs that do not need to be exposed to the public.
Prototyping and testing.

Best practices for API key authentication:

Use HTTPS to encrypt the API key in transit. By using HTTPS, you can encrypt the API key in transit to prevent it from being intercepted by attackers. This is especially important if you are using API key authentication over an unsecured network, such as a public Wi-Fi network.
Use short-lived API keys to reduce the risk of key theft. You can rotate the API key periodically to reduce the risk of theft. By rotating the API key, you can invalidate the old key and generate a new key for the user to use.
Use secure API keys. To prevent key theft, you should use secure API keys that are difficult to guess or brute-force. You can use random keys that are long and complex to prevent them from being easily guessed or brute-forced.
Use API key revocation to invalidate stolen or compromised keys. If an API key is stolen or compromised, you can invalidate the key on the server to prevent it from being used to access the user’s account.
Use rate limiting to prevent brute-force attacks. To prevent brute-force attacks, you can use rate limiting to limit the number of login attempts per user or IP address. If a user exceeds the login attempts, you can temporarily block the user or IP address to prevent further attempts.

IX. Conclusion

In this post, we have compared the most common authentication methods in API with Ruby on Rails. Each method has its own advantages and disadvantages, and the best method to use will depend on the specific requirements of your application. When choosing an authentication method, it is important to consider factors such as security, complexity, ease of implementation, and use cases. By choosing the right authentication method for your application, you can ensure that your users’ data is secure and protected from unauthorized access.

References:

I. Introduction#

II. Basic authentication#

III. OAuth authentication#

IV. Token base authentication#

V. JWT authentication#

VI. Session authentication#

VII. API key authentication#

IX. Conclusion#