What even are Cloudflare Durable Objects?
17 days ago
- #cloudflare
- #serverless
- #stateful
- Cloudflare Durable Objects (DOs) provide stateful serverless capabilities, allowing for long-lived connections and coordination without the operational overhead of traditional servers.
- DOs are unique per ID, ensuring global consistency and single-instance handling for specific IDs, unlike stateless serverless functions.
- They support multiple storage layers: in-memory state for active sessions, KV storage for metadata, SQLite for structured data, and external storage for large files.
- Parent-child relationships in DOs enable efficient multi-tenant applications by separating logical entities (e.g., workspaces and projects) into individual DOs.
- DOs can schedule operations with alarms, enabling just-in-time execution for tasks like subscription renewals without batch processing.
- The Hibernate API allows DOs to sleep while maintaining WebSocket connections, reducing costs and improving resource utilization.
- The Cloudflare Agents SDK simplifies building with DOs, offering features like WebSocket handling, HTTP routing, and task queues, even for non-AI applications.
- Common pitfalls include single-threaded processing per instance and the need to initialize DO identities explicitly.
- DOs are ideal for real-time collaboration, per-user databases, and coordinated tasks but not for large blobs or cross-user analytics.