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<h1 class="lined-header"><span>cowboy_static(3)</span></h1>
<div class="sect1">
<h2 id="_name">Name</h2>
<div class="sectionbody">
<div class="paragraph"><p>cowboy_static - Static file handler</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_description">Description</h2>
<div class="sectionbody">
<div class="paragraph"><p>The module <code>cowboy_static</code> implements file serving capabilities
using the REST semantics provided by <code>cowboy_rest</code>.</p></div>
<div class="paragraph"><p>The static file handler is a pre-written handler coming with
Cowboy. To serve files, use it in your routes.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_options">Options</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">opts</span></span>() <span style="color: #990000">::</span> {<span style="color: #FF6600">priv_file</span>, <span style="color: #009900">App</span>, <span style="color: #009900">Path</span>}
| {<span style="color: #FF6600">priv_file</span>, <span style="color: #009900">App</span>, <span style="color: #009900">Path</span>, <span style="color: #009900">Extra</span>}
| {<span style="color: #FF6600">file</span>, <span style="color: #009900">Path</span>}
| {<span style="color: #FF6600">file</span>, <span style="color: #009900">Path</span>, <span style="color: #009900">Extra</span>}
| {<span style="color: #FF6600">priv_dir</span>, <span style="color: #009900">App</span>, <span style="color: #009900">Path</span>}
| {<span style="color: #FF6600">priv_dir</span>, <span style="color: #009900">App</span>, <span style="color: #009900">Path</span>, <span style="color: #009900">Extra</span>}
| {<span style="color: #FF6600">dir</span>, <span style="color: #009900">Path</span>}
| {<span style="color: #FF6600">dir</span>, <span style="color: #009900">Path</span>, <span style="color: #009900">Extra</span>}
<span style="color: #009900">App</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">atom</span></span>()
<span style="color: #009900">Path</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>() | <span style="font-weight: bold"><span style="color: #000000">string</span></span>()
<span style="color: #009900">Extra</span> <span style="color: #990000">::</span> [<span style="color: #009900">Etag</span> | <span style="color: #009900">Mimetypes</span>]
<span style="color: #009900">Etag</span> <span style="color: #990000">::</span> {<span style="color: #FF6600">etag</span>, <span style="font-weight: bold"><span style="color: #000000">module</span></span>(), <span style="font-weight: bold"><span style="color: #000080">function</span></span>()}
| {<span style="color: #FF6600">etag</span>, <span style="color: #000080">false</span>}
<span style="color: #009900">Mimetypes</span> <span style="color: #990000">::</span> {<span style="color: #FF6600">mimetypes</span>, <span style="font-weight: bold"><span style="color: #000000">module</span></span>(), <span style="font-weight: bold"><span style="color: #000080">function</span></span>()}
| {<span style="color: #FF6600">mimetypes</span>, <span style="font-weight: bold"><span style="color: #000080">binary</span></span>() | <span style="color: #009900">ParsedMime</span>}
<span style="color: #009900">ParsedMime</span> <span style="color: #990000">::</span> {<span style="color: #009900">Type</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>(), <span style="color: #009900">SubType</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>(), <span style="color: #009900">Params</span>}
<span style="color: #009900">Params</span> <span style="color: #990000">::</span> [{<span style="color: #009900">Key</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>(), <span style="color: #009900">Value</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>()}]</tt></pre></div></div>
<div class="paragraph"><p>Static handler configuration.</p></div>
<div class="dlist"><dl>
<dt class="hdlist1">
priv_file
</dt>
<dd>
<p>
Send a file.
</p>
<div class="paragraph"><p>The path is relative to the given application’s private
directory.</p></div>
</dd>
<dt class="hdlist1">
file
</dt>
<dd>
<p>
Send a file.
</p>
<div class="paragraph"><p>The path is either absolute or relative to the Erlang node’s
current directory.</p></div>
</dd>
<dt class="hdlist1">
priv_dir
</dt>
<dd>
<p>
Recursively serve files from a directory.
</p>
<div class="paragraph"><p>The path is relative to the given application’s private
directory.</p></div>
</dd>
<dt class="hdlist1">
dir
</dt>
<dd>
<p>
Recursively serve files from a directory.
</p>
<div class="paragraph"><p>The path is either absolute or relative to the Erlang node’s
current directory.</p></div>
</dd>
</dl></div>
<div class="paragraph"><p>The extra options allow you to define how the etag should be
calculated and how the MIME type of files should be detected.</p></div>
<div class="paragraph"><p>By default the static handler will generate an etag based
on the size and modification time of the file. You may disable
the etag entirely with <code>{etag, false}</code> or provide a module
and function that will be called when needed:</p></div>
<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">generate_etag</span></span>(<span style="color: #009900">Path</span>, <span style="color: #009900">Size</span>, <span style="color: #009900">Mtime</span>) <span style="color: #990000">-></span> {<span style="color: #FF6600">strong</span> | <span style="color: #FF6600">weak</span>, <span style="font-weight: bold"><span style="color: #000080">binary</span></span>()}
<span style="color: #009900">Path</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>()
<span style="color: #009900">Size</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()
<span style="color: #009900">Mtime</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000000">file:date_time</span></span>()</tt></pre></div></div>
<div class="paragraph"><p>By default the static handler will detect Web-related MIME types
by looking at the file extension. You can provide a specific
MIME type that will always be used, or a module and function that
will be called when needed:</p></div>
<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">detect_mimetype</span></span>(<span style="color: #009900">Path</span>) <span style="color: #990000">-></span> <span style="color: #009900">ParsedMime</span>
<span style="color: #009900">Path</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>()
<span style="color: #009900">ParsedMime</span> <span style="color: #990000">::</span> {<span style="color: #009900">Type</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>(), <span style="color: #009900">SubType</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>(), <span style="color: #009900">Params</span>}
<span style="color: #009900">Params</span> <span style="color: #990000">::</span> [{<span style="color: #009900">Key</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>(), <span style="color: #009900">Value</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">binary</span></span>()}]</tt></pre></div></div>
<div class="paragraph"><p>Cowboy comes with two such functions; the default function
<code>cow_mimetypes:web/1</code>, and a second function generated from
the Apache <em>mime.types</em> file, <code>cow_mimetypes:all/1</code>.</p></div>
<div class="paragraph"><p>The MIME type function should return
<code>{<<"application">>, <<"octet-stream">>, []}</code>
when it fails to detect a file’s MIME type.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_changelog">Changelog</h2>
<div class="sectionbody">
<div class="ulist"><ul>
<li>
<p>
<strong>1.0</strong>: Handler introduced.
</p>
</li>
</ul></div>
</div>
</div>
<div class="sect1">
<h2 id="_examples">Examples</h2>
<div class="sectionbody">
<div class="listingblock">
<div class="title">Custom etag function</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="font-weight: bold"><span style="color: #000000">generate_etag</span></span>(<span style="color: #009900">Path</span>, <span style="color: #009900">Size</span>, <span style="color: #009900">Mtime</span>) <span style="color: #990000">-></span>
{<span style="color: #FF6600">strong</span>, <span style="font-weight: bold"><span style="color: #000000">integer_to_binary</span></span>(
<span style="font-weight: bold"><span style="color: #000000">erlang:phash2</span></span>({<span style="color: #009900">Path</span>, <span style="color: #009900">Size</span>, <span style="color: #009900">Mtime</span>}, <span style="color: #993399">16#ffffffff</span>))}<span style="color: #990000">.</span></tt></pre></div></div>
<div class="listingblock">
<div class="title">Custom MIME type function</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="font-weight: bold"><span style="color: #000000">always_octet_stream</span></span>(<span style="color: #009900">_Path</span>) <span style="color: #990000">-></span>
<span style="font-weight: bold"><span style="color: #0000FF">case</span></span> <span style="font-weight: bold"><span style="color: #000000">filename:extension</span></span>(<span style="color: #009900">Path</span>) <span style="font-weight: bold"><span style="color: #0000FF">of</span></span>
<span style="color: #990000"><<</span><span style="color: #FF0000">".erl"</span><span style="color: #990000">>></span> <span style="color: #990000">-></span> {<span style="color: #990000"><<</span><span style="color: #FF0000">"text"</span><span style="color: #990000">>></span>, <span style="color: #990000"><<</span><span style="color: #FF0000">"plain"</span><span style="color: #990000">>></span>, []};
<span style="color: #990000">_</span> <span style="color: #990000">-></span> {<span style="color: #990000"><<</span><span style="color: #FF0000">"application"</span><span style="color: #990000">>></span>, <span style="color: #990000"><<</span><span style="color: #FF0000">"octet-stream"</span><span style="color: #990000">>></span>, []}
<span style="font-weight: bold"><span style="color: #0000FF">end</span></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(7)</a>,
<a href="../cowboy_router">cowboy_router(3)</a></p></div>
</div>
</div>
</div>
<div class="span3 sidecol">
<h3>
Cowboy
2.4
Function Reference
</h3>
<ul>
<li><a href="/docs/en/cowboy/2.4/guide">User Guide</a></li>
<li><a href="/docs/en/cowboy/2.4/manual">Function Reference</a></li>
</ul>
<h4 id="docs-nav">Navigation</h4>
<h4>Version select</h4>
<ul>
<li><a href="/docs/en/cowboy/2.4/manual">2.4</a></li>
<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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