Serverless Redis with Upstash compatibility

This repo provides an HTTP server that interacts with the Redis database via HTTP requests. It supports compatibility with Upstash, a cloud service that provides Redis.

Technologies used:

• Hono: A lightweight framework for building high-performance HTTP servers in TypeScript. In this template, Hono is used to handle HTTP requests.
• Deno: A secure runtime for JavaScript and TypeScript.

Why use this template:

• Simple setup and high performance thanks to Hono.
• Easy to deploy on Railway.
• Compatible with Upstash, a cloud service that provides Redis.

Environment variables:

• REDIS_URL — connection string to the Redis instance (defaults to redis://localhost:6379).

• SR_TOKEN — bearer token required by clients.

• PORT / HOST — HTTP server bind address (default 0.0.0.0:3000).

• SR_IDLE_TIMEOUT_MS — idle timeout for the Redis connection in milliseconds. Defaults to 0 (the connection is kept open for the lifetime of the process, matching the previous behaviour). Any value greater than 0 will close the Redis connection after that many milliseconds of inactivity and re-open it on the next request.

  Useful for platforms like Railway serverless, where an active outbound TCP connection (e.g. to Redis) prevents the service from being put to sleep. Note that every reconnect pays the TCP/TLS/AUTH handshake cost, so pick a value that fits your traffic profile.

Limitations

This project aims to be compatible with the @upstash/redis HTTP client for the bulk of the command surface (strings, hashes, lists, sets, sorted sets, streams, scripting, bitops, geo, server commands, pipeline and base64 encoding). The following Upstash behaviours are intentionally out of scope:

• Pub/Sub (SUBSCRIBE, PSUBSCRIBE, PUBLISH): the request/response HTTP model cannot hold a long-lived subscription, so these commands will hang or return unexpected results.
• REST-style URL routes (e.g. POST /set/{key}/{value}, GET /get/{key}): only the array-form endpoints POST /, POST /pipeline and POST /multi-exec are implemented. Use the @upstash/redis client or send POST / -d '["SET","k","v"]' directly.
• MULTI/EXEC atomicity: the /multi-exec endpoint executes commands sequentially through ioredis without WATCH/MULTI/EXEC framing. The first failing command aborts the rest, and any successful commands before it stay committed. Treat it as a pipeline, not a real transaction.
• Connection-stateful commands (SELECT, CLIENT, RESET, SUBSCRIBE): every HTTP request may run on a fresh logical connection, especially when SR_IDLE_TIMEOUT_MS > 0, so state set by these commands is not guaranteed to persist across requests.