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<H1><A NAME="SECTION0021000000000000000000">
20. How to use streaming with CherryPy</A>
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<P>
If you need to return a very big page to a browser, then you might want to use streaming, which means that CherryPy
will start sending the page back to the browser before the page is completely built, and the page will
be returned in chunks.
<P>
All you need to do to use streaming is to use the <var>response.wfile</var> variable, which contains the socket used
to send the response back to the browser. You need to write <b>all</b> the data on the socket (including the
response header).
<P>
You also need to tell CherryPy that you've already sent the response to the browser and therefore it doesn't have to do it.
To do so, you need to set the <var>response.sendResponse</var> variable to 0.
<P>
The following code shows an example of how to use streaming:
<div class="verbatim"><pre>
import time
CherryClass Root:
view:
def index(self):
response.wfile.write("HTTP/1.1 200\r\n")
response.wfile.write("Content-Type: text/plain\r\n\r\n")
response.wfile.write("First line. Sleeping 2 seconds ...\n")
time.sleep(2)
response.wfile.write("Second line. Sleeping 2 seconds ...\n")
time.sleep(2)
response.wfile.write("Third and last line")
response.sendResponse = 0
return "" # The view still needs to return a string
</pre></div>
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<span class="release-info">Release 0.10, documentation updated on 19 March 2004.</span>
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