Add rate limiter and example

[neekolas]

Add a Redis-backed publish rate limiter and surface Retry-After with ResourceExhausted in gRPC responses while configuring a 10s Redis connect timeout across gateway setup

Introduce a concrete Redis-backed rate limit authorizer via authorizers.NewRateLimitAuthorizer, integrate GatewayServiceError with RetryAfter and ResourceExhausted handling in the gRPC interceptor, and update the gateway builder to create or reuse a Redis client with a configurable config.RedisOptions.ConnectTimeout set to 10s. Add a builder for rate limit authorizers, refactor nonce manager setup to accept a shared Redis client, and include a runnable example wiring the limiter into the gateway.

📍Where to Start

Start with the authorizers.NewRateLimitAuthorizer implementation and its usage in the interceptor path in pkg/gateway/authorizers/ratelimit.go and then review the gRPC error mapping in pkg/gateway/interceptor.go.

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📊 Macroscope summarized aeabe07. 11 files reviewed, 2 issues evaluated, 1 issue filtered, 0 comments posted

🗂️ Filtered Issues

pkg/gateway/builder.go — 0 comments posted, 1 evaluated, 1 filtered

• line 316: SetupRedisClient calls ctx.Err() (line 316) without guarding against a nil ctx. If any caller passes a nil context (which is possible because there is no visible guard or constructor guarantee preventing it), the method call panics with invalid memory address or nil pointer dereference, crashing the process before the Redis client is set up. Add an explicit nil check (e.g., return an error or substitute context.Background()) before dereferencing ctx. [ Out of scope ]

[neekolas]

• Add rate limiter and example #1255 👈 (View in Graphite)
• main

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