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<h1 class="lined-header"><span>cowboy_req:stream_trailers(3)</span></h1>
<div class="sect1">
<h2 id="_name">Name</h2>
<div class="sectionbody">
<div class="paragraph"><p>cowboy_req:stream_trailers - Send the response trailers</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_description">Description</h2>
<div class="sectionbody">
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #000000">stream_trailers</span></span>(<span style="color: #009900">Trailers</span>, <span style="color: #009900">Req</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000000">cowboy_req:req</span></span>()) <span style="color: #990000">-></span> <span style="color: #FF6600">ok</span>
<span style="color: #009900">Trailers</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000000">cowboy:http_headers</span></span>()</tt></pre></div></div>
<div class="paragraph"><p>Send the response trailers and terminate the stream.</p></div>
<div class="paragraph"><p>This function can only be called once, after initiating
a response using
<a href="../cowboy_req.stream_reply">cowboy_req:stream_reply(3)</a>
and sending zero or more body chunks using
<a href="../cowboy_req.stream_body">cowboy_req:stream_body(3)</a>
with the <code>nofin</code> argument set. The function <code>stream_trailers/2</code>
implies <code>fin</code> and automatically terminate the response.</p></div>
<div class="paragraph"><p>You must list all field names sent in trailers in the
trailer header, otherwise they might be dropped by intermediaries
or clients.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_arguments">Arguments</h2>
<div class="sectionbody">
<div class="dlist"><dl>
<dt class="hdlist1">
Trailers
</dt>
<dd>
<p>
Trailer field values to be sent.
</p>
</dd>
<dt class="hdlist1">
Req
</dt>
<dd>
<p>
The Req object.
</p>
</dd>
</dl></div>
</div>
</div>
<div class="sect1">
<h2 id="_return_value">Return value</h2>
<div class="sectionbody">
<div class="paragraph"><p>The atom <code>ok</code> is always returned. It can be safely ignored.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_changelog">Changelog</h2>
<div class="sectionbody">
<div class="ulist"><ul>
<li>
<p>
<strong>2.2</strong>: Function introduced.
</p>
</li>
</ul></div>
</div>
</div>
<div class="sect1">
<h2 id="_examples">Examples</h2>
<div class="sectionbody">
<div class="listingblock">
<div class="title">Stream a response body with trailers</div>
<div class="content"><!-- Generator: GNU source-highlight
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="color: #009900">Req</span> <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">cowboy_req:stream_reply</span></span>(<span style="color: #993399">200</span>, #{
<span style="color: #990000"><<</span><span style="color: #FF0000">"content-type"</span><span style="color: #990000">>></span> <span style="color: #990000">=></span> <span style="color: #990000"><<</span><span style="color: #FF0000">"text/plain"</span><span style="color: #990000">>></span>,
<span style="color: #990000"><<</span><span style="color: #FF0000">"trailer"</span><span style="color: #990000">>></span> <span style="color: #990000">=></span> <span style="color: #990000"><<</span><span style="color: #FF0000">"expires, content-md5"</span><span style="color: #990000">>></span>
}, <span style="color: #009900">Req0</span>),
<span style="font-weight: bold"><span style="color: #000000">cowboy_req:stream_body</span></span>(<span style="color: #990000"><<</span><span style="color: #FF0000">"Hello\n"</span><span style="color: #990000">>></span>, <span style="color: #FF6600">nofin</span>, <span style="color: #009900">Req</span>),
<span style="font-weight: bold"><span style="color: #000000">timer:sleep</span></span>(<span style="color: #993399">1000</span>),
<span style="font-weight: bold"><span style="color: #000000">cowboy_req:stream_body</span></span>(<span style="color: #990000"><<</span><span style="color: #FF0000">"World!\n"</span><span style="color: #990000">>></span>, <span style="color: #FF6600">nofin</span>, <span style="color: #009900">Req</span>)<span style="color: #990000">.</span>
<span style="font-weight: bold"><span style="color: #000000">cowboy_req:stream_trailers</span></span>(#{
<span style="color: #990000"><<</span><span style="color: #FF0000">"expires"</span><span style="color: #990000">>></span> <span style="color: #990000">=></span> <span style="color: #990000"><<</span><span style="color: #FF0000">"Sun, 10 Dec 2017 19:13:47 GMT"</span><span style="color: #990000">>></span>,
<span style="color: #990000"><<</span><span style="color: #FF0000">"content-md5"</span><span style="color: #990000">>></span> <span style="color: #990000">=></span> <span style="color: #990000"><<</span><span style="color: #FF0000">"fbf68a8e34b2ded53bba54e68794b4fe"</span><span style="color: #990000">>></span>
}, <span style="color: #009900">Req</span>)<span style="color: #990000">.</span></tt></pre></div></div>
</div>
</div>
<div class="sect1">
<h2 id="_see_also">See also</h2>
<div class="sectionbody">
<div class="paragraph"><p><a href="../cowboy_req">cowboy_req(3)</a>,
<a href="../cowboy_req.stream_reply">cowboy_req:stream_reply(3)</a>,
<a href="../cowboy_req.stream_body">cowboy_req:stream_body(3)</a></p></div>
</div>
</div>
</div>
<div class="span3 sidecol">
<h3>
Cowboy
2.3
Function Reference
</h3>
<ul>
<li><a href="/docs/en/cowboy/2.3/guide">User Guide</a></li>
<li><a href="/docs/en/cowboy/2.3/manual">Function Reference</a></li>
</ul>
<h4 id="docs-nav">Navigation</h4>
<h4>Version select</h4>
<ul>
<li><a href="/docs/en/cowboy/2.3/manual">2.3</a></li>
<li><a href="/docs/en/cowboy/2.2/manual">2.2</a></li>
<li><a href="/docs/en/cowboy/2.1/manual">2.1</a></li>
<li><a href="/docs/en/cowboy/2.0/manual">2.0</a></li>
<li><a href="/docs/en/cowboy/1.0/manual">1.0</a></li>
</ul>
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