API Authorization Strategies

1. Introduction

API authorization is a critical aspect of API security, ensuring that users can only access resources they are permitted to interact with. This lesson covers different strategies for API authorization within the context of microservices and API development.

2. Key Concepts

• Authorization: The process of determining if a user has permission to perform an action.
• Authentication vs. Authorization: Authentication verifies user identity, while authorization determines access rights.
• Scopes: Define the extent of the permissions granted to applications or users.
• Tokens: Used to manage session and permissions, often in the form of JWT (JSON Web Tokens).

3. Authorization Methods

Below are common strategies used for API authorization:

1. OAuth 2.0: A widely used authorization framework that allows third-party services to exchange access tokens.
2. API Keys: Simple tokens passed in the API request, used to identify the calling program.
3. JWT (JSON Web Tokens): Compact tokens representing claims to be transferred between two parties.
4. Role-Based Access Control (RBAC): Permissions are assigned to roles rather than individual users.

4. Step-by-Step Guide

Implementing OAuth 2.0 as an authorization strategy can be broken down into the following steps:

graph TD;
    A[Client Application] -->|Requests Token| B[Authorization Server]
    B -->|Redirects with Token| C[Resource Server]
    C -->|Validates Token| D[Protected Resource]
        

5. Best Practices

• Use HTTPS to secure data in transit.
• Implement token expiration and rotation policies.
• Regularly review and update access permissions.
• Log access attempts for auditing and monitoring.

6. FAQ