Implementation Effort and Use Cases of Different API Gateway Authorization Methods

API Gateway Authorization Methods: My quick evaluation

Intro

I'm developing a utility tool for my internal team using API Gateway + Lambda. One aspect I'd like to apply when it comes to securing APIs is limiting API access. AWS provides us three primary authorization methods exist: IAM, Amazon Cognito, and Lambda Authorizers. Here is my quick evaluation of each method's implementation effort, and ideal use cases.

Authorization Method Comparisons

1. IAM Authorization

Complexity: Low

Best For: Internal AWS environments

Implementation Effort: ⅕

Key Advantages:

• Native AWS ecosystem integration
• Minimal custom code requirements

Limitations:

• Restricted to AWS infrastructure
• Limited external user support

2. Amazon Cognito

Complexity: Medium

Best For: User-centric applications

Implementation Effort: ⅗

Key Advantages:

• Managed user authentication
• Built-in social login capabilities
• Multi-factor authentication support

Challenges:

• Requires initial configuration
• Steeper learning curve for advanced features

3. Lambda Authorizers

Complexity: High

Best For: Enterprise-level, custom authentication scenarios

Implementation Effort: 5/5

Key Advantages:

• Maximum authentication customization
• Supports intricate authentication logic
• Integrates with external identity providers

Challenges:

• Requires custom Lambda function development
• Higher maintenance overhead
• Potential performance implications

Recommendation Matrix

My closing thoughts

I'm developing some web-bases utility tools for my internal team. IAM Authorization seems a no-brainer to me. Minimal coding and configuration required helps me to ship fast to collect users' feedback as we also use AWS as our cloud provider.

In case, security concerns and authorization grow more complex, I'll look into Lambda Authorizers thanks to its flexibility while I'd like to avoid AWS Cognito as it requires steep learning curve when requirements are more complex.