When building applications that rely on databases (which is almost every application, right?), one of the biggest challenges developers face is testing how their code handles various error scenarios. What happens when the database returns a HTTP 400 error? How does your application respond to throttling? Will your retry logic work as expected?
These questions are crucial because, in production, errors are inevitable. This holds true for Azure Cosmos DB as well. The database’s distributed nature means that errors can arise from various sources, including network issues (503 Service Unavailable), request timeouts (408 Request timeout), rate limits (429 Too many requests), and more. Therefore, robust error handling and testing are essential to maintain a reliable application that handles these gracefully rather than crashing or losing data.