https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events

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 1. References
 2. Web APIs
 3. Server-sent events

Article Actions

  * English (US)

In this article

  * Concepts and usage
  * Interfaces
  * Examples
  * Specifications
  * See also

 1. Server-sent events
 2. Guides
     1. Using server-sent events
 3. Interfaces
     1. EventSource

In this article

  * Concepts and usage
  * Interfaces
  * Examples
  * Specifications
  * See also

Server-sent events

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.

Note: This feature is available in Web Workers

Note: Firefox does not currently support the use of server-sent
events in service workers (it does support them in dedicated and
shared workers). See Firefox bug 1681218.

Concepts and usage

To learn how to use server-sent events, see our article Using
server-sent events.

Interfaces

EventSource

    Defines all the features that handle connecting to a server,
    receiving events/data, errors, closing a connection, etc.

Examples

  * Simple SSE demo using PHP

Specifications

   Specification
HTML Standard
# server-sent-events

See also

Tools

  * Mercure: a real-time communication protocol (publish-subscribe)
    built on top of SSE
  * EventSource polyfill for Node.js
  * Remy Sharp's EventSource polyfill
  * Yaffle's EventSource polyfill
  * Rick Waldron's jquery plugin
  * intercooler.js declarative SSE support

Related Topics

  * AJAX
  * JavaScript
  * WebSockets

Other resources

  * A Twitter like application powered by server-sent events and its
    code on GitHub.
  * HTML5 and Server-sent events

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This page was last modified on May 3, 2023 by MDN contributors.

 

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