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diff --git a/app/static/doc/flask-docs/tutorial/dbcon.html b/app/static/doc/flask-docs/tutorial/dbcon.html new file mode 100644 index 0000000..91ed599 --- /dev/null +++ b/app/static/doc/flask-docs/tutorial/dbcon.html @@ -0,0 +1,154 @@ + +<!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>Step 4: Request Database Connections — 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="Tutorial" href="index.html" /> + <link rel="next" title="Step 5: The View Functions" href="views.html" /> + <link rel="prev" title="Step 3: Creating The Database" href="dbinit.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="views.html" title="Step 5: The View Functions" + accesskey="N">next</a> |</li> + <li class="right" > + <a href="dbinit.html" title="Step 3: Creating The Database" + accesskey="P">previous</a> |</li> + <li><a href="../index.html">Flask 0.8 documentation</a> »</li> + <li><a href="index.html" accesskey="U">Tutorial</a> »</li> + </ul> + </div> + + <div class="document"> + <div class="documentwrapper"> + <div class="bodywrapper"> + <div class="body"> + + <div class="section" id="step-4-request-database-connections"> +<span id="tutorial-dbcon"></span><h1>Step 4: Request Database Connections<a class="headerlink" href="#step-4-request-database-connections" title="Permalink to this headline">ΒΆ</a></h1> +<p>Now we know how we can open database connections and use them for scripts, +but how can we elegantly do that for requests? We will need the database +connection in all our functions so it makes sense to initialize them +before each request and shut them down afterwards.</p> +<p>Flask allows us to do that with the <a class="reference internal" href="../api.html#flask.Flask.before_request" title="flask.Flask.before_request"><tt class="xref py py-meth docutils literal"><span class="pre">before_request()</span></tt></a>, +<a class="reference internal" href="../api.html#flask.Flask.after_request" title="flask.Flask.after_request"><tt class="xref py py-meth docutils literal"><span class="pre">after_request()</span></tt></a> and <a class="reference internal" href="../api.html#flask.Flask.teardown_request" title="flask.Flask.teardown_request"><tt class="xref py py-meth docutils literal"><span class="pre">teardown_request()</span></tt></a> +decorators:</p> +<div class="highlight-python"><div class="highlight"><pre><span class="nd">@app.before_request</span> +<span class="k">def</span> <span class="nf">before_request</span><span class="p">():</span> + <span class="n">g</span><span class="o">.</span><span class="n">db</span> <span class="o">=</span> <span class="n">connect_db</span><span class="p">()</span> + +<span class="nd">@app.teardown_request</span> +<span class="k">def</span> <span class="nf">teardown_request</span><span class="p">(</span><span class="n">exception</span><span class="p">):</span> + <span class="n">g</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">close</span><span class="p">()</span> +</pre></div> +</div> +<p>Functions marked with <a class="reference internal" href="../api.html#flask.Flask.before_request" title="flask.Flask.before_request"><tt class="xref py py-meth docutils literal"><span class="pre">before_request()</span></tt></a> are called before +a request and passed no arguments. Functions marked with +<a class="reference internal" href="../api.html#flask.Flask.after_request" title="flask.Flask.after_request"><tt class="xref py py-meth docutils literal"><span class="pre">after_request()</span></tt></a> are called after a request and +passed the response that will be sent to the client. They have to return +that response object or a different one. They are however not guaranteed +to be executed if an exception is raised, this is where functions marked with +<a class="reference internal" href="../api.html#flask.Flask.teardown_request" title="flask.Flask.teardown_request"><tt class="xref py py-meth docutils literal"><span class="pre">teardown_request()</span></tt></a> come in. They get called after the +response has been constructed. They are not allowed to modify the request, and +their return values are ignored. If an exception occurred while the request was +being processed, it is passed to each function; otherwise, <cite>None</cite> is passed in.</p> +<p>We store our current database connection on the special <a class="reference internal" href="../api.html#flask.g" title="flask.g"><tt class="xref py py-data docutils literal"><span class="pre">g</span></tt></a> +object that Flask provides for us. This object stores information for one +request only and is available from within each function. Never store such +things on other objects because this would not work with threaded +environments. That special <a class="reference internal" href="../api.html#flask.g" title="flask.g"><tt class="xref py py-data docutils literal"><span class="pre">g</span></tt></a> object does some magic behind +the scenes to ensure it does the right thing.</p> +<p>Continue to <a class="reference internal" href="views.html#tutorial-views"><em>Step 5: The View Functions</em></a>.</p> +<div class="admonition hint"> +<p class="first admonition-title">Hint</p> +<p>Where do I put this code?</p> +<p>If you’ve been following along in this tutorial, you might be wondering +where to put the code from this step and the next. A logical place is to +group these module-level functions together, and put your new +<tt class="docutils literal"><span class="pre">before_request</span></tt> and <tt class="docutils literal"><span class="pre">teardown_request</span></tt> functions below your existing +<tt class="docutils literal"><span class="pre">init_db</span></tt> function (following the tutorial line-by-line).</p> +<p class="last">If you need a moment to find your bearings, take a look at how the <a class="reference external" href="http://github.com/mitsuhiko/flask/tree/master/examples/flaskr/">example +source</a> is organized. In Flask, you can put all of your application code +into a single Python module. You don’t have to, and if your app <a class="reference internal" href="../patterns/packages.html#larger-applications"><em>grows +larger</em></a>, it’s a good idea not to.</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>Related Topics</h3> +<ul> + <li><a href="../index.html">Documentation overview</a><ul> + <li><a href="index.html">Tutorial</a><ul> + <li>Previous: <a href="dbinit.html" title="previous chapter">Step 3: Creating The Database</a></li> + <li>Next: <a href="views.html" title="next chapter">Step 5: The View Functions</a></li> + </ul></li> + </ul></li> +</ul> + <h3>This Page</h3> + <ul class="this-page-menu"> + <li><a href="../_sources/tutorial/dbcon.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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