Error Handling Strategy

Error Handling Strategy

Overview

Good error handling improves debuggability, user experience, and system resilience. Inconsistent or leaky error handling is a common source of production pain.

When to Use

• Designing new services or APIs
• Reviewing existing error paths
• Standardizing error codes, messages, or exception hierarchies
• Improving observability of failures

Core Principles

• Fail fast for programmer errors; handle expected failures gracefully
• Preserve context (correlation IDs, causes) without leaking sensitive data
• Make errors actionable for both operators and (when appropriate) end users
• Prefer explicit error types/codes over generic catch-alls
• Log at the right level with enough context to diagnose

Recommended Practices

• Distinguish between domain/business errors and technical/infrastructure errors
• Use structured error responses for APIs
• Avoid exposing internal stack traces or secrets to clients
• Ensure transient errors are retried appropriately (see resilience patterns)
• Centralize mapping of internal errors to external representations where helpful

Verification

• Common failure modes have clear, consistent handling
• Logs and metrics make it possible to diagnose production errors
• User-facing messages are helpful without being dangerous