Class: Pgbus::Streams::WatermarkCacheMiddleware

Inherits:

Object

• Object
• Pgbus::Streams::WatermarkCacheMiddleware

Defined in:

lib/pgbus/streams/watermark_cache_middleware.rb

Overview

Rack middleware that clears the per-request thread-local watermark cache used by ‘Pgbus::StreamsHelper#pgbus_stream_from`. Without this middleware, a subsequent request served by the same thread would see stale `current_msg_id` values from the previous render — the pgbus_stream_from helper caches watermark lookups within a single request to avoid N+1 queries when a page uses multiple streams, and the cache would leak without a per-request boundary.

Installed automatically by ‘Pgbus::Engine` at boot.

Constant Summary

CACHE_KEY =

:pgbus_streams_watermark_cache

Instance Method Summary

• #call(env) ⇒ Object
• #initialize(app) ⇒ WatermarkCacheMiddleware constructor

  A new instance of WatermarkCacheMiddleware.

Constructor Details

#initialize(app) ⇒ WatermarkCacheMiddleware

Returns a new instance of WatermarkCacheMiddleware.

# File 'lib/pgbus/streams/watermark_cache_middleware.rb', line 17

def initialize(app)
  @app = app
end

Instance Method Details

#call(env) ⇒ Object

# File 'lib/pgbus/streams/watermark_cache_middleware.rb', line 21

def call(env)
  @app.call(env)
ensure
  Thread.current[CACHE_KEY] = nil
end