Solution: Track API Usage Metrics Transparently

Explore how to use the Proxy pattern to transparently monitor API usage metrics by intercepting method calls. Learn to track call counts dynamically without modifying original service methods, enabling you to add monitoring cleanly and efficiently in Node.js applications.

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Solution explanation
Revisit the problem statement

Solution explanation

Lines 2–10: We define the ApiService class that simulates two operations: fetchData() and postData().
- These represent typical API calls whose usage frequency we want to monitor.
- The goal is to track calls externally without changing the service implementation.
Lines 13–37: The createTrackedService() function constructs a Proxy that adds a transparent tracking layer.
- A target instance of ApiService is created as the real object.
- A stats object stores call counts per method name. ...

1.Introduction to Node.js Patterns

2.Factory Pattern: Generate Config-Driven Services Dynamically

3.Builder Pattern: Assemble Complex Objects with Fluent APIs

4.Decorator Pattern: Extend Behavior Without Modifying Core Logic

5.Adapter Pattern: Standardize Interface Across Dependencies

6.Proxy Pattern: Intercept and Control Access Transparently

7.Strategy Pattern: Swap Algorithms Based on Context

8.Wrapping Up

Solution: Track API Usage Metrics Transparently

Solution explanation