EVOLUTION-MANAGER

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<table width="100%" summary="page for cache_info {httr}"><tr><td>cache_info {httr}</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Compute caching information for a response.</h2>

<h3>Description</h3>

<p><code>cache_info()</code> gives details of cacheability of a response,
<code>rerequest()</code> re-performs the original request doing as little work
as possible (if not expired, returns response as is, or performs
revalidation if Etag or Last-Modified headers are present).
</p>

<h3>Usage</h3>

<pre>
cache_info(r)

rerequest(r)
</pre>

<h3>Arguments</h3>

<table summary="R argblock">
<tr valign="top"><td><code>r</code></td>
<td>
<p>A response</p>
</td></tr>
</table>

<h3>Examples</h3>

<pre>
# Never cached, always causes redownload
r1 &lt;- GET("https://www.google.com")
cache_info(r1)
r1$date
rerequest(r1)$date

# Expires in a year
r2 &lt;- GET("https://www.google.com/images/srpr/logo11w.png")
cache_info(r2)
r2$date
rerequest(r2)$date

# Has last-modified and etag, so does revalidation
r3 &lt;- GET("http://httpbin.org/cache")
cache_info(r3)
r3$date
rerequest(r3)$date

# Expires after 5 seconds
## Not run: 
r4 &lt;- GET("http://httpbin.org/cache/5")
cache_info(r4)
r4$date
rerequest(r4)$date
Sys.sleep(5)
cache_info(r4)
rerequest(r4)$date

## End(Not run)
</pre>

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