Note: This feature is available in Web Workers.
Traditionally, a web page has to send a request to the server to receive new data; that is, the page requests data from the server. With server-sent events, it's possible for a server to send new data to a web page at any time, by pushing messages to the web page. These incoming messages can be treated as Events + data inside the web page.
To learn how to use server-sent events, see our article Using server-sent events.
EventSourceDefines all the features that handle connecting to a server, receiving events/data, errors, closing a connection, etc.
| Specification |
|---|
| HTML> # server-sent-events> |
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https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events