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diff --git a/app/static/doc/flask-docs/unicode.html b/app/static/doc/flask-docs/unicode.html new file mode 100644 index 0000000..d5e4800 --- /dev/null +++ b/app/static/doc/flask-docs/unicode.html @@ -0,0 +1,215 @@ + +<!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>Unicode in Flask — 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="next" title="Flask Extension Development" href="extensiondev.html" /> + <link rel="prev" title="Security Considerations" href="security.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="extensiondev.html" title="Flask Extension Development" + accesskey="N">next</a> |</li> + <li class="right" > + <a href="security.html" title="Security Considerations" + accesskey="P">previous</a> |</li> + <li><a href="index.html">Flask 0.8 documentation</a> »</li> + </ul> + </div> + + <div class="document"> + <div class="documentwrapper"> + <div class="bodywrapper"> + <div class="body"> + + <div class="section" id="unicode-in-flask"> +<h1>Unicode in Flask<a class="headerlink" href="#unicode-in-flask" title="Permalink to this headline">¶</a></h1> +<p>Flask like Jinja2 and Werkzeug is totally Unicode based when it comes to +text. Not only these libraries, also the majority of web related Python +libraries that deal with text. If you don’t know Unicode so far, you +should probably read <a class="reference external" href="http://www.joelonsoftware.com/articles/Unicode.html">The Absolute Minimum Every Software Developer +Absolutely, Positively Must Know About Unicode and Character Sets</a>. This part of the +documentation just tries to cover the very basics so that you have a +pleasant experience with Unicode related things.</p> +<div class="section" id="automatic-conversion"> +<h2>Automatic Conversion<a class="headerlink" href="#automatic-conversion" title="Permalink to this headline">¶</a></h2> +<p>Flask has a few assumptions about your application (which you can change +of course) that give you basic and painless Unicode support:</p> +<ul class="simple"> +<li>the encoding for text on your website is UTF-8</li> +<li>internally you will always use Unicode exclusively for text except +for literal strings with only ASCII character points.</li> +<li>encoding and decoding happens whenever you are talking over a protocol +that requires bytes to be transmitted.</li> +</ul> +<p>So what does this mean to you?</p> +<p>HTTP is based on bytes. Not only the protocol, also the system used to +address documents on servers (so called URIs or URLs). However HTML which +is usually transmitted on top of HTTP supports a large variety of +character sets and which ones are used, are transmitted in an HTTP header. +To not make this too complex Flask just assumes that if you are sending +Unicode out you want it to be UTF-8 encoded. Flask will do the encoding +and setting of the appropriate headers for you.</p> +<p>The same is true if you are talking to databases with the help of +SQLAlchemy or a similar ORM system. Some databases have a protocol that +already transmits Unicode and if they do not, SQLAlchemy or your other ORM +should take care of that.</p> +</div> +<div class="section" id="the-golden-rule"> +<h2>The Golden Rule<a class="headerlink" href="#the-golden-rule" title="Permalink to this headline">¶</a></h2> +<p>So the rule of thumb: if you are not dealing with binary data, work with +Unicode. What does working with Unicode in Python 2.x mean?</p> +<ul class="simple"> +<li>as long as you are using ASCII charpoints only (basically numbers, +some special characters of latin letters without umlauts or anything +fancy) you can use regular string literals (<tt class="docutils literal"><span class="pre">'Hello</span> <span class="pre">World'</span></tt>).</li> +<li>if you need anything else than ASCII in a string you have to mark +this string as Unicode string by prefixing it with a lowercase <cite>u</cite>. +(like <tt class="docutils literal"><span class="pre">u'Hänsel</span> <span class="pre">und</span> <span class="pre">Gretel'</span></tt>)</li> +<li>if you are using non-Unicode characters in your Python files you have +to tell Python which encoding your file uses. Again, I recommend +UTF-8 for this purpose. To tell the interpreter your encoding you can +put the <tt class="docutils literal"><span class="pre">#</span> <span class="pre">-*-</span> <span class="pre">coding:</span> <span class="pre">utf-8</span> <span class="pre">-*-</span></tt> into the first or second line of +your Python source file.</li> +<li>Jinja is configured to decode the template files from UTF-8. So make +sure to tell your editor to save the file as UTF-8 there as well.</li> +</ul> +</div> +<div class="section" id="encoding-and-decoding-yourself"> +<h2>Encoding and Decoding Yourself<a class="headerlink" href="#encoding-and-decoding-yourself" title="Permalink to this headline">¶</a></h2> +<p>If you are talking with a filesystem or something that is not really based +on Unicode you will have to ensure that you decode properly when working +with Unicode interface. So for example if you want to load a file on the +filesystem and embed it into a Jinja2 template you will have to decode it +from the encoding of that file. Here the old problem that text files do +not specify their encoding comes into play. So do yourself a favour and +limit yourself to UTF-8 for text files as well.</p> +<p>Anyways. To load such a file with Unicode you can use the built-in +<tt class="xref py py-meth docutils literal"><span class="pre">str.decode()</span></tt> method:</p> +<div class="highlight-python"><div class="highlight"><pre><span class="k">def</span> <span class="nf">read_file</span><span class="p">(</span><span class="n">filename</span><span class="p">,</span> <span class="n">charset</span><span class="o">=</span><span class="s">'utf-8'</span><span class="p">):</span> + <span class="k">with</span> <span class="nb">open</span><span class="p">(</span><span class="n">filename</span><span class="p">,</span> <span class="s">'r'</span><span class="p">)</span> <span class="k">as</span> <span class="n">f</span><span class="p">:</span> + <span class="k">return</span> <span class="n">f</span><span class="o">.</span><span class="n">read</span><span class="p">()</span><span class="o">.</span><span class="n">decode</span><span class="p">(</span><span class="n">charset</span><span class="p">)</span> +</pre></div> +</div> +<p>To go from Unicode into a specific charset such as UTF-8 you can use the +<tt class="xref py py-meth docutils literal"><span class="pre">unicode.encode()</span></tt> method:</p> +<div class="highlight-python"><div class="highlight"><pre><span class="k">def</span> <span class="nf">write_file</span><span class="p">(</span><span class="n">filename</span><span class="p">,</span> <span class="n">contents</span><span class="p">,</span> <span class="n">charset</span><span class="o">=</span><span class="s">'utf-8'</span><span class="p">):</span> + <span class="k">with</span> <span class="nb">open</span><span class="p">(</span><span class="n">filename</span><span class="p">,</span> <span class="s">'w'</span><span class="p">)</span> <span class="k">as</span> <span class="n">f</span><span class="p">:</span> + <span class="n">f</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="n">contents</span><span class="o">.</span><span class="n">encode</span><span class="p">(</span><span class="n">charset</span><span class="p">))</span> +</pre></div> +</div> +</div> +<div class="section" id="configuring-editors"> +<h2>Configuring Editors<a class="headerlink" href="#configuring-editors" title="Permalink to this headline">¶</a></h2> +<p>Most editors save as UTF-8 by default nowadays but in case your editor is +not configured to do this you have to change it. Here some common ways to +set your editor to store as UTF-8:</p> +<ul> +<li><p class="first">Vim: put <tt class="docutils literal"><span class="pre">set</span> <span class="pre">enc=utf-8</span></tt> to your <tt class="docutils literal"><span class="pre">.vimrc</span></tt> file.</p> +</li> +<li><p class="first">Emacs: either use an encoding cookie or put this into your <tt class="docutils literal"><span class="pre">.emacs</span></tt> +file:</p> +<div class="highlight-python"><pre>(prefer-coding-system 'utf-8) +(setq default-buffer-file-coding-system 'utf-8)</pre> +</div> +</li> +<li><p class="first">Notepad++:</p> +<ol class="arabic simple"> +<li>Go to <em>Settings -> Preferences ...</em></li> +<li>Select the “New Document/Default Directory” tab</li> +<li>Select “UTF-8 without BOM” as encoding</li> +</ol> +<p>It is also recommended to use the Unix newline format, you can select +it in the same panel but this is not a requirement.</p> +</li> +</ul> +</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="#">Unicode in Flask</a><ul> +<li><a class="reference internal" href="#automatic-conversion">Automatic Conversion</a></li> +<li><a class="reference internal" href="#the-golden-rule">The Golden Rule</a></li> +<li><a class="reference internal" href="#encoding-and-decoding-yourself">Encoding and Decoding Yourself</a></li> +<li><a class="reference internal" href="#configuring-editors">Configuring Editors</a></li> +</ul> +</li> +</ul> +<h3>Related Topics</h3> +<ul> + <li><a href="index.html">Documentation overview</a><ul> + <li>Previous: <a href="security.html" title="previous chapter">Security Considerations</a></li> + <li>Next: <a href="extensiondev.html" title="next chapter">Flask Extension Development</a></li> + </ul></li> +</ul> + <h3>This Page</h3> + <ul class="this-page-menu"> + <li><a href="_sources/unicode.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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