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diff --git a/app/static/doc/flask-docs/patterns/urlprocessors.html b/app/static/doc/flask-docs/patterns/urlprocessors.html deleted file mode 100644 index 8e50e36..0000000 --- a/app/static/doc/flask-docs/patterns/urlprocessors.html +++ /dev/null @@ -1,237 +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>Using URL Processors — 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="Deploying with Distribute" href="distribute.html" /> - <link rel="prev" title="Application Dispatching" href="appdispatch.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="distribute.html" title="Deploying with Distribute" - accesskey="N">next</a> |</li> - <li class="right" > - <a href="appdispatch.html" title="Application Dispatching" - 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="using-url-processors"> -<h1>Using URL Processors<a class="headerlink" href="#using-url-processors" title="Permalink to this headline">¶</a></h1> -<p class="versionadded"> -<span class="versionmodified">New in version 0.7.</span></p> -<p>Flask 0.7 introduces the concept of URL processors. The idea is that you -might have a bunch of resources with common parts in the URL that you -don’t always explicitly want to provide. For instance you might have a -bunch of URLs that have the language code in it but you don’t want to have -to handle it in every single function yourself.</p> -<p>URL processors are especially helpful when combined with blueprints. We -will handle both application specific URL processors here as well as -blueprint specifics.</p> -<div class="section" id="internationalized-application-urls"> -<h2>Internationalized Application URLs<a class="headerlink" href="#internationalized-application-urls" title="Permalink to this headline">¶</a></h2> -<p>Consider an application like this:</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">Flask</span><span class="p">,</span> <span class="n">g</span> - -<span class="n">app</span> <span class="o">=</span> <span class="n">Flask</span><span class="p">(</span><span class="n">__name__</span><span class="p">)</span> - -<span class="nd">@app.route</span><span class="p">(</span><span class="s">'/<lang_code>/'</span><span class="p">)</span> -<span class="k">def</span> <span class="nf">index</span><span class="p">(</span><span class="n">lang_code</span><span class="p">):</span> - <span class="n">g</span><span class="o">.</span><span class="n">lang_code</span> <span class="o">=</span> <span class="n">lang_code</span> - <span class="o">...</span> - -<span class="nd">@app.route</span><span class="p">(</span><span class="s">'/<lang_code>/about'</span><span class="p">)</span> -<span class="k">def</span> <span class="nf">about</span><span class="p">(</span><span class="n">lang_code</span><span class="p">):</span> - <span class="n">g</span><span class="o">.</span><span class="n">lang_code</span> <span class="o">=</span> <span class="n">lang_code</span> - <span class="o">...</span> -</pre></div> -</div> -<p>This is an awful lot of repetition as you have to handle the language code -setting on the <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 yourself in every single function. -Sure, a decorator could be used to simplify this, but if you want to -generate URLs from one function to another you would have to still provide -the language code explicitly which can be annoying.</p> -<p>For the latter, this is where <a class="reference internal" href="../api.html#flask.Flask.url_defaults" title="flask.Flask.url_defaults"><tt class="xref py py-func docutils literal"><span class="pre">url_defaults()</span></tt></a> functions -come in. They can automatically inject values into a call for -<a class="reference internal" href="../api.html#flask.url_for" title="flask.url_for"><tt class="xref py py-func docutils literal"><span class="pre">url_for()</span></tt></a> automatically. The code below checks if the -language code is not yet in the dictionary of URL values and if the -endpoint wants a value named <tt class="docutils literal"><span class="pre">'lang_code'</span></tt>:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="nd">@app.url_defaults</span> -<span class="k">def</span> <span class="nf">add_language_code</span><span class="p">(</span><span class="n">endpoint</span><span class="p">,</span> <span class="n">values</span><span class="p">):</span> - <span class="k">if</span> <span class="s">'lang_code'</span> <span class="ow">in</span> <span class="n">values</span> <span class="ow">or</span> <span class="ow">not</span> <span class="n">g</span><span class="o">.</span><span class="n">lang_code</span><span class="p">:</span> - <span class="k">return</span> - <span class="k">if</span> <span class="n">app</span><span class="o">.</span><span class="n">url_map</span><span class="o">.</span><span class="n">is_endpoint_expecting</span><span class="p">(</span><span class="n">endpoint</span><span class="p">,</span> <span class="s">'lang_code'</span><span class="p">):</span> - <span class="n">values</span><span class="p">[</span><span class="s">'lang_code'</span><span class="p">]</span> <span class="o">=</span> <span class="n">g</span><span class="o">.</span><span class="n">lang_code</span> -</pre></div> -</div> -<p>The method <a class="reference external" href="http://werkzeug.pocoo.org/docs/routing/#werkzeug.routing.Map.is_endpoint_expecting" title="(in Werkzeug v0.7)"><tt class="xref py py-meth docutils literal"><span class="pre">is_endpoint_expecting()</span></tt></a> of the URL -map can be used to figure out if it would make sense to provide a language -code for the given endpoint.</p> -<p>The reverse of that function are -<a class="reference internal" href="../api.html#flask.Flask.url_value_preprocessor" title="flask.Flask.url_value_preprocessor"><tt class="xref py py-meth docutils literal"><span class="pre">url_value_preprocessor()</span></tt></a>s. They are executed right -after the request was matched and can execute code based on the URL -values. The idea is that they pull information out of the values -dictionary and put it somewhere else:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="nd">@app.url_value_preprocessor</span> -<span class="k">def</span> <span class="nf">pull_lang_code</span><span class="p">(</span><span class="n">endpoint</span><span class="p">,</span> <span class="n">values</span><span class="p">):</span> - <span class="n">g</span><span class="o">.</span><span class="n">lang_code</span> <span class="o">=</span> <span class="n">values</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="s">'lang_code'</span><span class="p">,</span> <span class="bp">None</span><span class="p">)</span> -</pre></div> -</div> -<p>That way you no longer have to do the <cite>lang_code</cite> assigment to -<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> in every function. You can further improve that by -writing your own decorator that prefixes URLs with the language code, but -the more beautiful solution is using a blueprint. Once the -<tt class="docutils literal"><span class="pre">'lang_code'</span></tt> is popped from the values dictionary and it will no longer -be forwarded to the view function reducing the code to this:</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">Flask</span><span class="p">,</span> <span class="n">g</span> - -<span class="n">app</span> <span class="o">=</span> <span class="n">Flask</span><span class="p">(</span><span class="n">__name__</span><span class="p">)</span> - -<span class="nd">@app.url_defaults</span> -<span class="k">def</span> <span class="nf">add_language_code</span><span class="p">(</span><span class="n">endpoint</span><span class="p">,</span> <span class="n">values</span><span class="p">):</span> - <span class="k">if</span> <span class="s">'lang_code'</span> <span class="ow">in</span> <span class="n">values</span> <span class="ow">or</span> <span class="ow">not</span> <span class="n">g</span><span class="o">.</span><span class="n">lang_code</span><span class="p">:</span> - <span class="k">return</span> - <span class="k">if</span> <span class="n">app</span><span class="o">.</span><span class="n">url_map</span><span class="o">.</span><span class="n">is_endpoint_expecting</span><span class="p">(</span><span class="n">endpoint</span><span class="p">,</span> <span class="s">'lang_code'</span><span class="p">):</span> - <span class="n">values</span><span class="p">[</span><span class="s">'lang_code'</span><span class="p">]</span> <span class="o">=</span> <span class="n">g</span><span class="o">.</span><span class="n">lang_code</span> - -<span class="nd">@app.url_value_preprocessor</span> -<span class="k">def</span> <span class="nf">pull_lang_code</span><span class="p">(</span><span class="n">endpoint</span><span class="p">,</span> <span class="n">values</span><span class="p">):</span> - <span class="n">g</span><span class="o">.</span><span class="n">lang_code</span> <span class="o">=</span> <span class="n">values</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="s">'lang_code'</span><span class="p">,</span> <span class="bp">None</span><span class="p">)</span> - -<span class="nd">@app.route</span><span class="p">(</span><span class="s">'/<lang_code>/'</span><span class="p">)</span> -<span class="k">def</span> <span class="nf">index</span><span class="p">():</span> - <span class="o">...</span> - -<span class="nd">@app.route</span><span class="p">(</span><span class="s">'/<lang_code>/about'</span><span class="p">)</span> -<span class="k">def</span> <span class="nf">about</span><span class="p">():</span> - <span class="o">...</span> -</pre></div> -</div> -</div> -<div class="section" id="internationalized-blueprint-urls"> -<h2>Internationalized Blueprint URLs<a class="headerlink" href="#internationalized-blueprint-urls" title="Permalink to this headline">¶</a></h2> -<p>Because blueprints can automatically prefix all URLs with a common string -it’s easy to automatically do that for every function. Furthermore -blueprints can have per-blueprint URL processors which removes a whole lot -of logic from the <a class="reference internal" href="../api.html#flask.Flask.url_defaults" title="flask.Flask.url_defaults"><tt class="xref py py-meth docutils literal"><span class="pre">url_defaults()</span></tt></a> function because it no -longer has to check if the URL is really interested in a <tt class="docutils literal"><span class="pre">'lang_code'</span></tt> -parameter:</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">Blueprint</span><span class="p">,</span> <span class="n">g</span> - -<span class="n">bp</span> <span class="o">=</span> <span class="n">Blueprint</span><span class="p">(</span><span class="s">'frontend'</span><span class="p">,</span> <span class="n">__name__</span><span class="p">,</span> <span class="n">url_prefix</span><span class="o">=</span><span class="s">'/<lang_code>'</span><span class="p">)</span> - -<span class="nd">@bp.url_defaults</span> -<span class="k">def</span> <span class="nf">add_language_code</span><span class="p">(</span><span class="n">endpoint</span><span class="p">,</span> <span class="n">values</span><span class="p">):</span> - <span class="n">values</span><span class="o">.</span><span class="n">setdefault</span><span class="p">(</span><span class="s">'lang_code'</span><span class="p">,</span> <span class="n">g</span><span class="o">.</span><span class="n">lang_code</span><span class="p">)</span> - -<span class="nd">@bp.url_value_preprocessor</span> -<span class="k">def</span> <span class="nf">pull_lang_code</span><span class="p">(</span><span class="n">endpoint</span><span class="p">,</span> <span class="n">values</span><span class="p">):</span> - <span class="n">g</span><span class="o">.</span><span class="n">lang_code</span> <span class="o">=</span> <span class="n">values</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="s">'lang_code'</span><span class="p">)</span> - -<span class="nd">@bp.route</span><span class="p">(</span><span class="s">'/'</span><span class="p">)</span> -<span class="k">def</span> <span class="nf">index</span><span class="p">():</span> - <span class="o">...</span> - -<span class="nd">@bp.route</span><span class="p">(</span><span class="s">'/about'</span><span class="p">)</span> -<span class="k">def</span> <span class="nf">about</span><span class="p">():</span> - <span class="o">...</span> -</pre></div> -</div> -</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="#">Using URL Processors</a><ul> -<li><a class="reference internal" href="#internationalized-application-urls">Internationalized Application URLs</a></li> -<li><a class="reference internal" href="#internationalized-blueprint-urls">Internationalized Blueprint URLs</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="appdispatch.html" title="previous chapter">Application Dispatching</a></li> - <li>Next: <a href="distribute.html" title="next chapter">Deploying with Distribute</a></li> - </ul></li> - </ul></li> -</ul> - <h3>This Page</h3> - <ul class="this-page-menu"> - <li><a href="../_sources/patterns/urlprocessors.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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