= cowboy_http2(3)

== Name

cowboy_http2 - HTTP/2

== Description

The module `cowboy_http2` implements HTTP/2
as a Ranch protocol.

== Types

=== opts()

[source,erlang]
----
opts() :: #{
    env             := cowboy_middleware:env(),
    middlewares     := [module()],
    preface_timeout := timeout()
}
----

Configuration for the HTTP/2 protocol.

This configuration is passed to Cowboy when starting listeners
using `cowboy:start_clear/4` or `cowboy:start_tls/4` functions.

It can be updated without restarting listeners using the
Ranch functions `ranch:get_protocol_options/1` and
`ranch:set_protocol_options/2`.

=== Option descriptions

The default value is given next to the option name.

env (#{})::
    Middleware environment.

middlewares ([cowboy_router, cowboy_handler])::
    Middlewares to run for every request.

preface_timeout (5000)::
    Time in ms Cowboy is willing to wait for the connection preface.

== Changelog

* *2.0*: Protocol introduced.

== See also

link:man:cowboy(7)[cowboy(7)],
link:man:cowboy_http(3)[cowboy_http(3)],
link:man:cowboy_websocket(3)[cowboy_websocket(3)]
