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diff --git a/studio/static/doc/flask-docs/patterns/streaming.html b/studio/static/doc/flask-docs/patterns/streaming.html deleted file mode 100644 index 9285ec4..0000000 --- a/studio/static/doc/flask-docs/patterns/streaming.html +++ /dev/null @@ -1,172 +0,0 @@ - -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" - "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> - - -<html xmlns="http://www.w3.org/1999/xhtml"> - <head> - <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> - - <title>Streaming Contents — Flask 0.8 documentation</title> - - <link rel="stylesheet" href="../_static/flasky.css" type="text/css" /> - <link rel="stylesheet" href="../_static/pygments.css" type="text/css" /> - - <script type="text/javascript"> - var DOCUMENTATION_OPTIONS = { - URL_ROOT: '../', - VERSION: '0.8', - COLLAPSE_INDEX: false, - FILE_SUFFIX: '.html', - HAS_SOURCE: true - }; - </script> - <script type="text/javascript" src="../_static/jquery.js"></script> - <script type="text/javascript" src="../_static/underscore.js"></script> - <script type="text/javascript" src="../_static/doctools.js"></script> - <link rel="top" title="Flask 0.8 documentation" href="../index.html" /> - <link rel="up" title="Patterns for Flask" href="index.html" /> - <link rel="next" title="Deferred Request Callbacks" href="deferredcallbacks.html" /> - <link rel="prev" title="Adding a favicon" href="favicon.html" /> - - - <link rel="apple-touch-icon" href="../_static/touch-icon.png" /> - - <link media="only screen and (max-device-width: 480px)" href="../_static/small_flask.css" type= "text/css" rel="stylesheet" /> - - </head> - <body> - <div class="related"> - <h3>Navigation</h3> - <ul> - <li class="right" style="margin-right: 10px"> - <a href="../genindex.html" title="General Index" - accesskey="I">index</a></li> - <li class="right" > - <a href="deferredcallbacks.html" title="Deferred Request Callbacks" - accesskey="N">next</a> |</li> - <li class="right" > - <a href="favicon.html" title="Adding a favicon" - accesskey="P">previous</a> |</li> - <li><a href="../index.html">Flask 0.8 documentation</a> »</li> - <li><a href="index.html" accesskey="U">Patterns for Flask</a> »</li> - </ul> - </div> - - <div class="document"> - <div class="documentwrapper"> - <div class="bodywrapper"> - <div class="body"> - - <div class="section" id="streaming-contents"> -<h1>Streaming Contents<a class="headerlink" href="#streaming-contents" title="Permalink to this headline">¶</a></h1> -<p>Sometimes you want to send an enormous amount of data to the client, much -more than you want to keep in memory. When you are generating the data on -the fly though, how do you send that back to the client without the -roundtrip to the filesystem?</p> -<p>The answer is by using generators and direct responses.</p> -<div class="section" id="basic-usage"> -<h2>Basic Usage<a class="headerlink" href="#basic-usage" title="Permalink to this headline">¶</a></h2> -<p>This is a basic view function that generates a lot of CSV data on the fly. -The trick is to have an inner function that uses a generator to generate -data and to then invoke that function and pass it to a response object:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">flask</span> <span class="kn">import</span> <span class="n">Response</span> - -<span class="nd">@app.route</span><span class="p">(</span><span class="s">'/large.csv'</span><span class="p">)</span> -<span class="k">def</span> <span class="nf">generate_large_csv</span><span class="p">():</span> - <span class="k">def</span> <span class="nf">generate</span><span class="p">():</span> - <span class="k">for</span> <span class="n">row</span> <span class="ow">in</span> <span class="n">iter_all_rows</span><span class="p">():</span> - <span class="k">yield</span> <span class="s">','</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">row</span><span class="p">)</span> <span class="o">+</span> <span class="s">'</span><span class="se">\n</span><span class="s">'</span> - <span class="k">return</span> <span class="n">Response</span><span class="p">(</span><span class="n">generate</span><span class="p">(),</span> <span class="n">mimetype</span><span class="o">=</span><span class="s">'text/csv'</span><span class="p">)</span> -</pre></div> -</div> -<p>Each <tt class="docutils literal"><span class="pre">yield</span></tt> expression is directly sent to the browser. Now though -that some WSGI middlewares might break streaming, so be careful there in -debug environments with profilers and other things you might have enabled.</p> -</div> -<div class="section" id="streaming-from-templates"> -<h2>Streaming from Templates<a class="headerlink" href="#streaming-from-templates" title="Permalink to this headline">¶</a></h2> -<p>The Jinja2 template engine also supports rendering templates piece by -piece. This functionality is not directly exposed by Flask because it is -quite uncommon, but you can easily do it yourself:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">flask</span> <span class="kn">import</span> <span class="n">Response</span> - -<span class="k">def</span> <span class="nf">stream_template</span><span class="p">(</span><span class="n">template_name</span><span class="p">,</span> <span class="o">**</span><span class="n">context</span><span class="p">):</span> - <span class="n">app</span><span class="o">.</span><span class="n">update_template_context</span><span class="p">(</span><span class="n">context</span><span class="p">)</span> - <span class="n">t</span> <span class="o">=</span> <span class="n">app</span><span class="o">.</span><span class="n">jinja_env</span><span class="o">.</span><span class="n">get_template</span><span class="p">(</span><span class="n">template_name</span><span class="p">)</span> - <span class="n">rv</span> <span class="o">=</span> <span class="n">t</span><span class="o">.</span><span class="n">stream</span><span class="p">(</span><span class="n">context</span><span class="p">)</span> - <span class="n">rv</span><span class="o">.</span><span class="n">enable_buffering</span><span class="p">(</span><span class="mi">5</span><span class="p">)</span> - <span class="k">return</span> <span class="n">rv</span> - -<span class="nd">@app.route</span><span class="p">(</span><span class="s">'/my-large-page.html'</span><span class="p">)</span> -<span class="k">def</span> <span class="nf">render_large_template</span><span class="p">():</span> - <span class="n">rows</span> <span class="o">=</span> <span class="n">iter_all_rows</span><span class="p">()</span> - <span class="k">return</span> <span class="n">Response</span><span class="p">(</span><span class="n">stream_template</span><span class="p">(</span><span class="s">'the_template.html'</span><span class="p">,</span> <span class="n">rows</span><span class="o">=</span><span class="n">rows</span><span class="p">))</span> -</pre></div> -</div> -<p>The trick here is to get the template object from the Jinja2 environment -on the application and to call <tt class="xref py py-meth docutils literal"><span class="pre">stream()</span></tt> instead of -<tt class="xref py py-meth docutils literal"><span class="pre">render()</span></tt> which returns a stream object instead of a -string. Since we’re bypassing the Flask template render functions and -using the template object itself we have to make sure to update the render -context ourselves by calling <a class="reference internal" href="../api.html#flask.Flask.update_template_context" title="flask.Flask.update_template_context"><tt class="xref py py-meth docutils literal"><span class="pre">update_template_context()</span></tt></a>. -The template is then evaluated as the stream is iterated over. Since each -time you do a yield the server will flush the content to the client you -might want to buffer up a few items in the template which you can do with -<tt class="docutils literal"><span class="pre">rv.enable_buffering(size)</span></tt>. <tt class="docutils literal"><span class="pre">5</span></tt> is a sane default.</p> -</div> -</div> - - - </div> - </div> - </div> - <div class="sphinxsidebar"> - <div class="sphinxsidebarwrapper"><p class="logo"><a href="../index.html"> - <img class="logo" src="../_static/flask.png" alt="Logo"/> -</a></p> - <h3><a href="../index.html">Table Of Contents</a></h3> - <ul> -<li><a class="reference internal" href="#">Streaming Contents</a><ul> -<li><a class="reference internal" href="#basic-usage">Basic Usage</a></li> -<li><a class="reference internal" href="#streaming-from-templates">Streaming from Templates</a></li> -</ul> -</li> -</ul> -<h3>Related Topics</h3> -<ul> - <li><a href="../index.html">Documentation overview</a><ul> - <li><a href="index.html">Patterns for Flask</a><ul> - <li>Previous: <a href="favicon.html" title="previous chapter">Adding a favicon</a></li> - <li>Next: <a href="deferredcallbacks.html" title="next chapter">Deferred Request Callbacks</a></li> - </ul></li> - </ul></li> -</ul> - <h3>This Page</h3> - <ul class="this-page-menu"> - <li><a href="../_sources/patterns/streaming.txt" - rel="nofollow">Show Source</a></li> - </ul> -<div id="searchbox" style="display: none"> - <h3>Quick search</h3> - <form class="search" action="../search.html" method="get"> - <input type="text" name="q" /> - <input type="submit" value="Go" /> - <input type="hidden" name="check_keywords" value="yes" /> - <input type="hidden" name="area" value="default" /> - </form> - <p class="searchtip" style="font-size: 90%"> - Enter search terms or a module, class or function name. - </p> -</div> -<script type="text/javascript">$('#searchbox').show(0);</script> - </div> - </div> - <div class="clearer"></div> - </div> - <div class="footer"> - © Copyright 2010, Armin Ronacher. - Created using <a href="http://sphinx.pocoo.org/">Sphinx</a>. - </div> - </body> -</html>
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