Upstash Integration

@dsar/upstash provides Upstash-backed DSAR runtime integrations. It currently exports an Upstash Redis-backed RateLimitStore for public intake endpoints. Use it for serverless or edge-friendly deployments where a fetch-based Redis client is preferred.

Install

bun add @dsar/upstash @upstash/redis

@upstash/redis is a peer dependency so host applications control the client version and environment variable setup.

Runtime Wiring

import { dsarInstance } from "@dsar/backend";
import { makeUpstashRateLimitStore } from "@dsar/upstash";
import { Redis } from "@upstash/redis";

const redis = Redis.fromEnv();

const runtime = dsarInstance({
	config: {
		rateLimit: {
			intake: {
				ip: {
					limit: 60,
					windowMs: 60_000,
				},
				tenant: {
					limit: 300,
					windowMs: 60_000,
				},
			},
			store: makeUpstashRateLimitStore({
				client: redis,
				keyPrefix: "dsar:rate-limit",
			}),
		},
	},
	repos: {
		persistence:
			/* see examples/config/runtime.config.example.ts or provide
			   runtimeReposFromPersistence(...) output */,
	},
});

Behavior

• Uses the backend fixed-window rate-limit contract.
• Shares IP and tenant counters across runtime instances.
• Returns the same 429 and Retry-After behavior as the default store.
• Automatically expires Upstash Redis keys after the configured window.
• Applies keyPrefix before DSAR's route/scope key. Use an empty string only when the host application already namespaces keys.

Production Notes

• Use this package for serverless and fetch-oriented deployments.
• Use @dsar/redis for long-running Node/server deployments with ioredis.
• Keep config.rateLimit.onLimitExceeded wired to your metrics pipeline when you need visibility into abusive or misconfigured public intake sources.