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<h1 class="lined-header"><span>cowboy_middleware(3)</span></h1>

<div class="sect1">
<h2 id="_name">Name</h2>
<div class="sectionbody">
<div class="paragraph"><p>cowboy_middleware - behaviour for middlewares</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_description">Description</h2>
<div class="sectionbody">
<div class="paragraph"><p>The <code>cowboy_middleware</code> behaviour defines the interface used
by Cowboy middleware modules.</p></div>
<div class="paragraph"><p>Middlewares process the request sequentially in the order they
are configured.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_types">Types</h2>
<div class="sectionbody">
<div class="sect2">
<h3 id="_env_atom_any">env() = [{atom(), any()}]</h3>
<div class="paragraph"><p>The environment variable.</p></div>
<div class="paragraph"><p>One is created for every request. It is passed to each
middleware module executed and subsequently returned,
optionally with its contents modified.</p></div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_callbacks">Callbacks</h2>
<div class="sectionbody">
<div class="sect2">
<h3 id="_execute_req_env_8594_ok_req_env_suspend_module_function_args_stop_req">execute(Req, Env) &#8594; {ok, Req, Env} | {suspend, Module, Function, Args} | {stop, Req}</h3>
<div class="dlist"><dl>
<dt class="hdlist1">
Req = cowboy_req:req()
</dt>
<dd>
<p>
The Req object.
</p>
</dd>
<dt class="hdlist1">
Env = env()
</dt>
<dd>
<p>
The request environment.
</p>
</dd>
<dt class="hdlist1">
Module = module()
</dt>
<dd>
<p>
MFA to call when resuming the process.
</p>
</dd>
<dt class="hdlist1">
Function = atom()
</dt>
<dd>
<p>
MFA to call when resuming the process.
</p>
</dd>
<dt class="hdlist1">
Args = [any()]
</dt>
<dd>
<p>
MFA to call when resuming the process.
</p>
</dd>
</dl></div>
<div class="paragraph"><p>Execute the middleware.</p></div>
<div class="paragraph"><p>The <code>ok</code> return value indicates that everything went well
and that Cowboy should continue processing the request. A
response may or may not have been sent.</p></div>
<div class="paragraph"><p>The <code>suspend</code> return value will hibernate the process until
an Erlang message is received. Note that when resuming, any
previous stacktrace information will be gone.</p></div>
<div class="paragraph"><p>The <code>stop</code> return value stops Cowboy from doing any further
processing of the request, even if there are middlewares
that haven&#8217;t been executed yet. The connection may be left
open to receive more requests from the client.</p></div>
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	Cowboy
	2.0
	Function Reference
	
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