How do data exchange approaches differ between Message Broker and REST API?

Message Broker and REST API are two different approaches to data exchange between systems.

Message Broker:

• Uses an intermediary (message broker) that receives, stores, and forwards messages.
• Supports asynchronous data exchange: sender and receiver do not need to operate simultaneously.
• Supports queues, topics, message routing.
• Suitable for high-load systems, distributed systems where reliability and scalability are important.

REST API:

• Based on HTTP protocol and REST architectural style.
• Data exchange is synchronous: the client sends a request and waits for a response.
• Uses standard HTTP methods (GET, POST, PUT, DELETE).
• Suitable for direct interaction between client and server when simplicity and transparency are required.

Key differences:

• Synchronous vs. Asynchronous: REST is synchronous, Message Broker is asynchronous.
• Communication: REST — direct, Message Broker — via intermediary.
• Reliability: Message Broker can guarantee message delivery, REST depends on network connection.

Example: for sending notifications that do not need immediate processing, Message Broker is preferable. For data retrieval on request, REST API is suitable.