It is a behavioral design pattern that allows us to define a family of algorithms, encapsulate each one in a separate class and select the appropriate one based on the situation. This pattern is useful when multiple algorithms can be used for a specific task, and the choice of which one to use can be made dynamically at runtime.
Instead of hardcoding an algorithm inside a class, we delegate the actual implementation to different strategy classes. It is often used to isolate the business logic of a class from the implementation details of algorithms that may not be as important in the context of that logic.
- Strategy Interface: Defines a contract that all concrete strategies must follow.
- Concrete Strategies: Different implementations of the strategy interface.
- Context: A class that uses a strategy object to execute a behavior without knowing which specific algorithm is being used.
- Payment Processing: Selecting different payment gateways (PayPal, Stripe, etc.).
- Authentication Mechanisms: Choosing between OAuth, JWT, or basic authentication (Passportjs).
- Logging Mechanism: Dynamically choosing file-based logging, console logging, or cloud-based logging (Winston).