Consolidate Three Partner APIs into a Query Service

Question

Design a query service that consolidates three partner APIs into a single interface for easier access and management.

Codemia · Accepted Answer

To begin, we need to define the requirements for our query service. The service should:
1. Provide a unified interface for querying data from three different partner APIs.
2. Support filtering, sorting, and pagination of results.
3. Handle authentication and authorization for each API.
4. Ensure high availability and low latency in response times.

The high-level architecture of the query service can be broken down into several components:
- **API Gateway**: This will serve as the entry point for client requests, routing them to the appropriate service.
- **Service Layer**: This layer will handle the business logic, including calling the partner APIs, aggregating the data, and formatting the response.
- **Data Caching**: Implement caching mechanisms to store frequently accessed data, reducing the number of calls to the partner APIs.
- **Load Balancer**: To ensure scalability, we can use a load balancer to distribute incoming requests across multiple instances of the service.

In the service layer, we will implement a strategy to call the partner APIs concurrently. We can use asynchronous programming to make non-blocking calls, which will improve the response time. Each API call will be wrapped in a try-catch block to handle errors gracefully. If one API fails, we can decide whether to return partial results or an error message, depending on the business requirements.

When designing this system, we must consider trade-offs such as:
- **Complexity vs. Simplicity**: A more complex architecture may offer better performance but can be harder to maintain.
- **Consistency vs. Availability**: In cases of API failure, we must decide whether to prioritize returning consistent data or ensuring availability.
To scale the service, we can implement horizontal scaling by adding more instances and using a distributed caching solution to handle increased load.

To manage errors, we will implement a robust logging system to track API failures and response times. We can also use circuit breakers to prevent cascading failures. For data consistency, we will define a strategy for merging responses from the APIs, ensuring that if one API returns outdated data, we can still provide a coherent response to the client.

Consolidate Three Partner APIs into a Query Service

Expedia

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