React useEventSource Hook Simplifies Server-Sent Events with Auto-Reconnect

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A new React hook called useEventSource, available via the @reactuses/core package, offers a declarative way to consume Server-Sent Events (SSE) in React applications. SSE is a native browser protocol built on plain HTTP that has existed since 2011, enabling one-directional, server-to-client data streaming for use cases like live notifications, stock tickers, and AI response streaming. The hook manages connection lifecycle automatically, exposing data, status, and error as component state, eliminating the need for manual event listener setup and teardown. A companion hook, useFetchEventSource, addresses a key limitation of the native EventSource API — its inability to send custom headers or POST requests — which is increasingly relevant for authenticated AI-completion endpoints. The post highlights common bugs in hand-rolled SSE implementations, including infinite silent reconnects and opaque error handling, which the hook is designed to prevent.

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