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diff --git a/guide/upgrade_protocol.md b/guide/upgrade_protocol.md deleted file mode 100644 index db7a453..0000000 --- a/guide/upgrade_protocol.md +++ /dev/null @@ -1,37 +0,0 @@ -Protocol upgrades -================= - -Cowboy features many different handlers, each for different purposes. -All handlers have a common entry point: the `init/3` function. - -The default handler type is the simple HTTP handler. - -To switch to a different protocol, you must perform a protocol -upgrade. This is what is done for Websocket and REST and is -explained in details in the respective chapters. - -You can also create your own protocol on top of Cowboy and use -the protocol upgrade mechanism to switch to it. - -For example, if you create the `my_protocol` module implementing -the `cowboy_sub_protocol` behavior, then you can upgrade to it -by simply returning the module name from `init/3`. - -``` erlang -init(_, _, _Opts) -> - {upgrade, protocol, my_protocol}. -``` - -The `cowboy_sub_protocol` behavior only requires one callback, -`upgrade/4`. It receives the Req object, the middleware environment, -and the handler and options for this request. This is the same -module as the `init/3` function and the same options that were -passed to it. - -``` erlang -upgrade(Req, Env, Handler, HandlerOpts) -> - %% ... -``` - -This callback is expected to behave like a middleware. Please -see the corresponding chapter for more information. |