Apache HTTP Server Version 2.5

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# Apache Module mod_proxy_wstunnel

Available Languages: en | fr

Description: | Websockets support module for `mod_proxy`
Status: | Extension
Module Identifier: | proxy_wstunnel_module
Source File: | mod_proxy_wstunnel.c
Compatibility: | Available in httpd 2.4.5 and later

### Summary

This module requires the service of `mod_proxy`. It provides support for the tunnelling of web socket connections to a backend websockets server. The connection is automatically upgraded to a websocket connection:

### HTTP Response

    Upgrade: WebSocket
    Connection: Upgrade

Proxying requests to a websockets server like `echo.websocket.org` can be done using the `ProxyPass` directive:

    ProxyPass "/ws2/"  "ws://echo.websocket.org/"
    ProxyPass "/wss2/" "wss://echo.websocket.org/"

Load balancing for multiple backends can be achieved using `mod_proxy_balancer`.

In fact the module can be used to upgrade to other protocols, you can set the `upgrade` parameter in the `ProxyPass` directive to allow the module to accept other protocol. NONE means you bypass the check for the header but still upgrade to WebSocket. ANY means that `Upgrade` will read in the request headers and use in the response `Upgrade`

### Directives

### Bugfix checklist

- httpd changelog
- Known issues
- Report a bug

### See also

- `mod_proxy`
- Comments

## ProxyWebsocketAsync Directive ¶

Description: | Instructs this module to try to create an asynchronous tunnel
Syntax: | `ProxyWebsocketAsync ON|OFF`
Context: | server config, virtual host
Status: | Extension
Module: | mod_proxy_wstunnel

This directive instructs the server to try to create an asynchronous tunnel. If the current MPM does not support the necessary features, a synchronous tunnel is used.

### Note

Async support is experimental and subject to change.

## ProxyWebsocketAsyncDelay Directive ¶

Description: | Sets the amount of time the tunnel waits synchronously for data
Syntax: | `ProxyWebsocketAsyncDelay num[ms]`
Default: | `ProxyWebsocketAsyncDelay 0`
Context: | server config, virtual host
Status: | Extension
Module: | mod_proxy_wstunnel

If `ProxyWebsocketAsync` is enabled, this directive controls how long the server synchronously waits for more data. The timeout is considered in seconds by default, but it is possible to increase the time resolution to milliseconds adding the ms suffix.

### Note

Async support is experimental and subject to change.

## ProxyWebsocketIdleTimeout Directive ¶

Description: | Sets the maximum amount of time to wait for data on the websockets tunnel
Syntax: | `ProxyWebsocketIdleTimeout num[ms]`
Default: | `ProxyWebsocketIdleTimeout 0`
Context: | server config, virtual host
Status: | Extension
Module: | mod_proxy_wstunnel

This directive imposes a maximum amount of time for the tunnel to be left open while idle. The timeout is considered in seconds by default, but it is possible to increase the time resolution to milliseconds adding the ms suffix.

Available Languages: en | fr

## Comments

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