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diff --git a/app/static/doc/flask-docs/config.html b/app/static/doc/flask-docs/config.html deleted file mode 100644 index c569e8f..0000000 --- a/app/static/doc/flask-docs/config.html +++ /dev/null @@ -1,505 +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>Configuration Handling — 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="Signals" href="signals.html" /> - <link rel="prev" title="Handling Application Errors" href="errorhandling.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="signals.html" title="Signals" - accesskey="N">next</a> |</li> - <li class="right" > - <a href="errorhandling.html" title="Handling Application Errors" - 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="configuration-handling"> -<span id="config"></span><h1>Configuration Handling<a class="headerlink" href="#configuration-handling" title="Permalink to this headline">¶</a></h1> -<p class="versionadded"> -<span class="versionmodified">New in version 0.3.</span></p> -<p>Applications need some kind of configuration. There are different settings -you might want to change depending on the application environment like -toggling the debug mode, setting the secret key, and other such -environment-specific things.</p> -<p>The way Flask is designed usually requires the configuration to be -available when the application starts up. You can hardcode the -configuration in the code, which for many small applications is not -actually that bad, but there are better ways.</p> -<p>Independent of how you load your config, there is a config object -available which holds the loaded configuration values: -The <a class="reference internal" href="api.html#flask.Flask.config" title="flask.Flask.config"><tt class="xref py py-attr docutils literal"><span class="pre">config</span></tt></a> attribute of the <a class="reference internal" href="api.html#flask.Flask" title="flask.Flask"><tt class="xref py py-class docutils literal"><span class="pre">Flask</span></tt></a> -object. This is the place where Flask itself puts certain configuration -values and also where extensions can put their configuration values. But -this is also where you can have your own configuration.</p> -<div class="section" id="configuration-basics"> -<h2>Configuration Basics<a class="headerlink" href="#configuration-basics" title="Permalink to this headline">¶</a></h2> -<p>The <a class="reference internal" href="api.html#flask.Flask.config" title="flask.Flask.config"><tt class="xref py py-attr docutils literal"><span class="pre">config</span></tt></a> is actually a subclass of a dictionary and -can be modified just like any dictionary:</p> -<div class="highlight-python"><div class="highlight"><pre><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="n">app</span><span class="o">.</span><span class="n">config</span><span class="p">[</span><span class="s">'DEBUG'</span><span class="p">]</span> <span class="o">=</span> <span class="bp">True</span> -</pre></div> -</div> -<p>Certain configuration values are also forwarded to the -<a class="reference internal" href="api.html#flask.Flask" title="flask.Flask"><tt class="xref py py-attr docutils literal"><span class="pre">Flask</span></tt></a> object so you can read and write them from there:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="n">app</span><span class="o">.</span><span class="n">debug</span> <span class="o">=</span> <span class="bp">True</span> -</pre></div> -</div> -<p>To update multiple keys at once you can use the <a class="reference external" href="http://docs.python.org/dev/library/stdtypes.html#dict.update" title="(in Python v3.3)"><tt class="xref py py-meth docutils literal"><span class="pre">dict.update()</span></tt></a> -method:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="n">app</span><span class="o">.</span><span class="n">config</span><span class="o">.</span><span class="n">update</span><span class="p">(</span> - <span class="n">DEBUG</span><span class="o">=</span><span class="bp">True</span><span class="p">,</span> - <span class="n">SECRET_KEY</span><span class="o">=</span><span class="s">'...'</span> -<span class="p">)</span> -</pre></div> -</div> -</div> -<div class="section" id="builtin-configuration-values"> -<h2>Builtin Configuration Values<a class="headerlink" href="#builtin-configuration-values" title="Permalink to this headline">¶</a></h2> -<p>The following configuration values are used internally by Flask:</p> -<table border="1" class="docutils"> -<colgroup> -<col width="45%" /> -<col width="55%" /> -</colgroup> -<tbody valign="top"> -<tr class="row-odd"><td><tt class="docutils literal"><span class="pre">DEBUG</span></tt></td> -<td>enable/disable debug mode</td> -</tr> -<tr class="row-even"><td><tt class="docutils literal"><span class="pre">TESTING</span></tt></td> -<td>enable/disable testing mode</td> -</tr> -<tr class="row-odd"><td><tt class="docutils literal"><span class="pre">PROPAGATE_EXCEPTIONS</span></tt></td> -<td>explicitly enable or disable the -propagation of exceptions. If not set or -explicitly set to <cite>None</cite> this is -implicitly true if either <cite>TESTING</cite> or -<cite>DEBUG</cite> is true.</td> -</tr> -<tr class="row-even"><td><tt class="docutils literal"><span class="pre">PRESERVE_CONTEXT_ON_EXCEPTION</span></tt></td> -<td>By default if the application is in -debug mode the request context is not -popped on exceptions to enable debuggers -to introspect the data. This can be -disabled by this key. You can also use -this setting to force-enable it for non -debug execution which might be useful to -debug production applications (but also -very risky).</td> -</tr> -<tr class="row-odd"><td><tt class="docutils literal"><span class="pre">SECRET_KEY</span></tt></td> -<td>the secret key</td> -</tr> -<tr class="row-even"><td><tt class="docutils literal"><span class="pre">SESSION_COOKIE_NAME</span></tt></td> -<td>the name of the session cookie</td> -</tr> -<tr class="row-odd"><td><tt class="docutils literal"><span class="pre">SESSION_COOKIE_DOMAIN</span></tt></td> -<td>the domain for the session cookie. If -this is not set, the cookie will be -valid for all subdomains of -<tt class="docutils literal"><span class="pre">SERVER_NAME</span></tt>.</td> -</tr> -<tr class="row-even"><td><tt class="docutils literal"><span class="pre">SESSION_COOKIE_PATH</span></tt></td> -<td>the path for the session cookie. If -this is not set the cookie will be valid -for all of <tt class="docutils literal"><span class="pre">APPLICATION_ROOT</span></tt> or if -that is not set for <tt class="docutils literal"><span class="pre">'/'</span></tt>.</td> -</tr> -<tr class="row-odd"><td><tt class="docutils literal"><span class="pre">SESSION_COOKIE_HTTPONLY</span></tt></td> -<td>controls if the cookie should be set -with the httponly flag. Defaults to -<cite>True</cite>.</td> -</tr> -<tr class="row-even"><td><tt class="docutils literal"><span class="pre">SESSION_COOKIE_SECURE</span></tt></td> -<td>controls if the cookie should be set -with the secure flag. Defaults to -<cite>False</cite>.</td> -</tr> -<tr class="row-odd"><td><tt class="docutils literal"><span class="pre">PERMANENT_SESSION_LIFETIME</span></tt></td> -<td>the lifetime of a permanent session as -<a class="reference external" href="http://docs.python.org/dev/library/datetime.html#datetime.timedelta" title="(in Python v3.3)"><tt class="xref py py-class docutils literal"><span class="pre">datetime.timedelta</span></tt></a> object. -Starting with Flask 0.8 this can also be -an integer representing seconds.</td> -</tr> -<tr class="row-even"><td><tt class="docutils literal"><span class="pre">USE_X_SENDFILE</span></tt></td> -<td>enable/disable x-sendfile</td> -</tr> -<tr class="row-odd"><td><tt class="docutils literal"><span class="pre">LOGGER_NAME</span></tt></td> -<td>the name of the logger</td> -</tr> -<tr class="row-even"><td><tt class="docutils literal"><span class="pre">SERVER_NAME</span></tt></td> -<td>the name and port number of the server. -Required for subdomain support (e.g.: -<tt class="docutils literal"><span class="pre">'myapp.dev:5000'</span></tt>) Note that -localhost does not support subdomains so -setting this to “localhost” does not -help.</td> -</tr> -<tr class="row-odd"><td><tt class="docutils literal"><span class="pre">APPLICATION_ROOT</span></tt></td> -<td>If the application does not occupy -a whole domain or subdomain this can -be set to the path where the application -is configured to live. This is for -session cookie as path value. If -domains are used, this should be -<tt class="docutils literal"><span class="pre">None</span></tt>.</td> -</tr> -<tr class="row-even"><td><tt class="docutils literal"><span class="pre">MAX_CONTENT_LENGTH</span></tt></td> -<td>If set to a value in bytes, Flask will -reject incoming requests with a -content length greater than this by -returning a 413 status code.</td> -</tr> -<tr class="row-odd"><td><tt class="docutils literal"><span class="pre">TRAP_HTTP_EXCEPTIONS</span></tt></td> -<td>If this is set to <tt class="docutils literal"><span class="pre">True</span></tt> Flask will -not execute the error handlers of HTTP -exceptions but instead treat the -exception like any other and bubble it -through the exception stack. This is -helpful for hairy debugging situations -where you have to find out where an HTTP -exception is coming from.</td> -</tr> -<tr class="row-even"><td><tt class="docutils literal"><span class="pre">TRAP_BAD_REQUEST_ERRORS</span></tt></td> -<td>Werkzeug’s internal data structures that -deal with request specific data will -raise special key errors that are also -bad request exceptions. Likewise many -operations can implicitly fail with a -BadRequest exception for consistency. -Since it’s nice for debugging to know -why exactly it failed this flag can be -used to debug those situations. If this -config is set to <tt class="docutils literal"><span class="pre">True</span></tt> you will get -a regular traceback instead.</td> -</tr> -</tbody> -</table> -<div class="admonition-more-on-server-name admonition "> -<p class="first admonition-title">More on <tt class="docutils literal"><span class="pre">SERVER_NAME</span></tt></p> -<p>The <tt class="docutils literal"><span class="pre">SERVER_NAME</span></tt> key is used for the subdomain support. Because -Flask cannot guess the subdomain part without the knowledge of the -actual server name, this is required if you want to work with -subdomains. This is also used for the session cookie.</p> -<p class="last">Please keep in mind that not only Flask has the problem of not knowing -what subdomains are, your web browser does as well. Most modern web -browsers will not allow cross-subdomain cookies to be set on a -server name without dots in it. So if your server name is -<tt class="docutils literal"><span class="pre">'localhost'</span></tt> you will not be able to set a cookie for -<tt class="docutils literal"><span class="pre">'localhost'</span></tt> and every subdomain of it. Please chose a different -server name in that case, like <tt class="docutils literal"><span class="pre">'myapplication.local'</span></tt> and add -this name + the subdomains you want to use into your host config -or setup a local <a class="reference external" href="https://www.isc.org/software/bind">bind</a>.</p> -</div> -<p class="versionadded"> -<span class="versionmodified">New in version 0.4: </span><tt class="docutils literal"><span class="pre">LOGGER_NAME</span></tt></p> -<p class="versionadded"> -<span class="versionmodified">New in version 0.5: </span><tt class="docutils literal"><span class="pre">SERVER_NAME</span></tt></p> -<p class="versionadded"> -<span class="versionmodified">New in version 0.6: </span><tt class="docutils literal"><span class="pre">MAX_CONTENT_LENGTH</span></tt></p> -<p class="versionadded"> -<span class="versionmodified">New in version 0.7: </span><tt class="docutils literal"><span class="pre">PROPAGATE_EXCEPTIONS</span></tt>, <tt class="docutils literal"><span class="pre">PRESERVE_CONTEXT_ON_EXCEPTION</span></tt></p> -<p class="versionadded"> -<span class="versionmodified">New in version 0.8: </span><tt class="docutils literal"><span class="pre">TRAP_BAD_REQUEST_ERRORS</span></tt>, <tt class="docutils literal"><span class="pre">TRAP_HTTP_EXCEPTIONS</span></tt>, -<tt class="docutils literal"><span class="pre">APPLICATION_ROOT</span></tt>, <tt class="docutils literal"><span class="pre">SESSION_COOKIE_DOMAIN</span></tt>, -<tt class="docutils literal"><span class="pre">SESSION_COOKIE_PATH</span></tt>, <tt class="docutils literal"><span class="pre">SESSION_COOKIE_HTTPONLY</span></tt>, -<tt class="docutils literal"><span class="pre">SESSION_COOKIE_SECURE</span></tt></p> -</div> -<div class="section" id="configuring-from-files"> -<h2>Configuring from Files<a class="headerlink" href="#configuring-from-files" title="Permalink to this headline">¶</a></h2> -<p>Configuration becomes more useful if you can store it in a separate file, -ideally located outside the actual application package. This makes -packaging and distributing your application possible via various package -handling tools (<a class="reference internal" href="patterns/distribute.html#distribute-deployment"><em>Deploying with Distribute</em></a>) and finally modifying the -configuration file afterwards.</p> -<p>So a common pattern is this:</p> -<div class="highlight-python"><div class="highlight"><pre><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="n">app</span><span class="o">.</span><span class="n">config</span><span class="o">.</span><span class="n">from_object</span><span class="p">(</span><span class="s">'yourapplication.default_settings'</span><span class="p">)</span> -<span class="n">app</span><span class="o">.</span><span class="n">config</span><span class="o">.</span><span class="n">from_envvar</span><span class="p">(</span><span class="s">'YOURAPPLICATION_SETTINGS'</span><span class="p">)</span> -</pre></div> -</div> -<p>This first loads the configuration from the -<cite>yourapplication.default_settings</cite> module and then overrides the values -with the contents of the file the <span class="target" id="index-0"></span><tt class="xref std std-envvar docutils literal"><span class="pre">YOURAPPLICATION_SETTINGS</span></tt> -environment variable points to. This environment variable can be set on -Linux or OS X with the export command in the shell before starting the -server:</p> -<div class="highlight-python"><pre>$ export YOURAPPLICATION_SETTINGS=/path/to/settings.cfg -$ python run-app.py - * Running on http://127.0.0.1:5000/ - * Restarting with reloader...</pre> -</div> -<p>On Windows systems use the <cite>set</cite> builtin instead:</p> -<div class="highlight-python"><pre>>set YOURAPPLICATION_SETTINGS=\path\to\settings.cfg</pre> -</div> -<p>The configuration files themselves are actual Python files. Only values -in uppercase are actually stored in the config object later on. So make -sure to use uppercase letters for your config keys.</p> -<p>Here is an example of a configuration file:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="c"># Example configuration</span> -<span class="n">DEBUG</span> <span class="o">=</span> <span class="bp">False</span> -<span class="n">SECRET_KEY</span> <span class="o">=</span> <span class="s">'?</span><span class="se">\xbf</span><span class="s">,</span><span class="se">\xb4\x8d\xa3</span><span class="s">"<</span><span class="se">\x9c\xb0</span><span class="s">@</span><span class="se">\x0f</span><span class="s">5</span><span class="se">\xab</span><span class="s">,w</span><span class="se">\xee\x8d</span><span class="s">$0</span><span class="se">\x13\x8b</span><span class="s">83'</span> -</pre></div> -</div> -<p>Make sure to load the configuration very early on, so that extensions have -the ability to access the configuration when starting up. There are other -methods on the config object as well to load from individual files. For a -complete reference, read the <a class="reference internal" href="api.html#flask.Config" title="flask.Config"><tt class="xref py py-class docutils literal"><span class="pre">Config</span></tt></a> object’s -documentation.</p> -</div> -<div class="section" id="configuration-best-practices"> -<h2>Configuration Best Practices<a class="headerlink" href="#configuration-best-practices" title="Permalink to this headline">¶</a></h2> -<p>The downside with the approach mentioned earlier is that it makes testing -a little harder. There is no single 100% solution for this problem in -general, but there are a couple of things you can keep in mind to improve -that experience:</p> -<ol class="arabic simple"> -<li>create your application in a function and register blueprints on it. -That way you can create multiple instances of your application with -different configurations attached which makes unittesting a lot -easier. You can use this to pass in configuration as needed.</li> -<li>Do not write code that needs the configuration at import time. If you -limit yourself to request-only accesses to the configuration you can -reconfigure the object later on as needed.</li> -</ol> -</div> -<div class="section" id="development-production"> -<h2>Development / Production<a class="headerlink" href="#development-production" title="Permalink to this headline">¶</a></h2> -<p>Most applications need more than one configuration. There should be at -least separate configurations for the production server and the one used -during development. The easiest way to handle this is to use a default -configuration that is always loaded and part of the version control, and a -separate configuration that overrides the values as necessary as mentioned -in the example above:</p> -<div class="highlight-python"><div class="highlight"><pre><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="n">app</span><span class="o">.</span><span class="n">config</span><span class="o">.</span><span class="n">from_object</span><span class="p">(</span><span class="s">'yourapplication.default_settings'</span><span class="p">)</span> -<span class="n">app</span><span class="o">.</span><span class="n">config</span><span class="o">.</span><span class="n">from_envvar</span><span class="p">(</span><span class="s">'YOURAPPLICATION_SETTINGS'</span><span class="p">)</span> -</pre></div> -</div> -<p>Then you just have to add a separate <cite>config.py</cite> file and export -<tt class="docutils literal"><span class="pre">YOURAPPLICATION_SETTINGS=/path/to/config.py</span></tt> and you are done. However -there are alternative ways as well. For example you could use imports or -subclassing.</p> -<p>What is very popular in the Django world is to make the import explicit in -the config file by adding an <tt class="docutils literal"><span class="pre">from</span> <span class="pre">yourapplication.default_settings</span> -<span class="pre">import</span> <span class="pre">*</span></tt> to the top of the file and then overriding the changes by hand. -You could also inspect an environment variable like -<tt class="docutils literal"><span class="pre">YOURAPPLICATION_MODE</span></tt> and set that to <cite>production</cite>, <cite>development</cite> etc -and import different hardcoded files based on that.</p> -<p>An interesting pattern is also to use classes and inheritance for -configuration:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="k">class</span> <span class="nc">Config</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span> - <span class="n">DEBUG</span> <span class="o">=</span> <span class="bp">False</span> - <span class="n">TESTING</span> <span class="o">=</span> <span class="bp">False</span> - <span class="n">DATABASE_URI</span> <span class="o">=</span> <span class="s">'sqlite://:memory:'</span> - -<span class="k">class</span> <span class="nc">ProductionConfig</span><span class="p">(</span><span class="n">Config</span><span class="p">):</span> - <span class="n">DATABASE_URI</span> <span class="o">=</span> <span class="s">'mysql://user@localhost/foo'</span> - -<span class="k">class</span> <span class="nc">DevelopmentConfig</span><span class="p">(</span><span class="n">Config</span><span class="p">):</span> - <span class="n">DEBUG</span> <span class="o">=</span> <span class="bp">True</span> - -<span class="k">class</span> <span class="nc">TestingConfig</span><span class="p">(</span><span class="n">Config</span><span class="p">):</span> - <span class="n">TESTING</span> <span class="o">=</span> <span class="bp">True</span> -</pre></div> -</div> -<p>To enable such a config you just have to call into -<a class="reference internal" href="api.html#flask.Config.from_object" title="flask.Config.from_object"><tt class="xref py py-meth docutils literal"><span class="pre">from_object()</span></tt></a>:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="n">app</span><span class="o">.</span><span class="n">config</span><span class="o">.</span><span class="n">from_object</span><span class="p">(</span><span class="s">'configmodule.ProductionConfig'</span><span class="p">)</span> -</pre></div> -</div> -<p>There are many different ways and it’s up to you how you want to manage -your configuration files. However here a list of good recommendations:</p> -<ul class="simple"> -<li>keep a default configuration in version control. Either populate the -config with this default configuration or import it in your own -configuration files before overriding values.</li> -<li>use an environment variable to switch between the configurations. -This can be done from outside the Python interpreter and makes -development and deployment much easier because you can quickly and -easily switch between different configs without having to touch the -code at all. If you are working often on different projects you can -even create your own script for sourcing that activates a virtualenv -and exports the development configuration for you.</li> -<li>Use a tool like <a class="reference external" href="http://fabfile.org/">fabric</a> in production to push code and -configurations separately to the production server(s). For some -details about how to do that, head over to the -<a class="reference internal" href="patterns/fabric.html#fabric-deployment"><em>Deploying with Fabric</em></a> pattern.</li> -</ul> -</div> -<div class="section" id="instance-folders"> -<span id="id1"></span><h2>Instance Folders<a class="headerlink" href="#instance-folders" title="Permalink to this headline">¶</a></h2> -<p class="versionadded"> -<span class="versionmodified">New in version 0.8.</span></p> -<p>Flask 0.8 introduces instance folders. Flask for a long time made it -possible to refer to paths relative to the application’s folder directly -(via <tt class="xref py py-attr docutils literal"><span class="pre">Flask.root_path</span></tt>). This was also how many developers loaded -configurations stored next to the application. Unfortunately however this -only works well if applications are not packages in which case the root -path refers to the contents of the package.</p> -<p>With Flask 0.8 a new attribute was introduced: -<tt class="xref py py-attr docutils literal"><span class="pre">Flask.instance_path</span></tt>. It refers to a new concept called the -“instance folder”. The instance folder is designed to not be under -version control and be deployment specific. It’s the perfect place to -drop things that either change at runtime or configuration files.</p> -<p>You can either explicitly provide the path of the instance folder when -creating the Flask application or you can let Flask autodetect the -instance folder. For explicit configuration use the <cite>instance_path</cite> -parameter:</p> -<div class="highlight-python"><div class="highlight"><pre><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="n">instance_path</span><span class="o">=</span><span class="s">'/path/to/instance/folder'</span><span class="p">)</span> -</pre></div> -</div> -<p>Please keep in mind that this path <em>must</em> be absolute when provided.</p> -<p>If the <cite>instance_path</cite> parameter is not provided the following default -locations are used:</p> -<ul> -<li><p class="first">Uninstalled module:</p> -<div class="highlight-python"><pre>/myapp.py -/instance</pre> -</div> -</li> -<li><p class="first">Uninstalled package:</p> -<div class="highlight-python"><pre>/myapp - /__init__.py -/instance</pre> -</div> -</li> -<li><p class="first">Installed module or package:</p> -<div class="highlight-python"><pre>$PREFIX/lib/python2.X/site-packages/myapp -$PREFIX/var/myapp-instance</pre> -</div> -<p><tt class="docutils literal"><span class="pre">$PREFIX</span></tt> is the prefix of your Python installation. This can be -<tt class="docutils literal"><span class="pre">/usr</span></tt> or the path to your virtualenv. You can print the value of -<tt class="docutils literal"><span class="pre">sys.prefix</span></tt> to see what the prefix is set to.</p> -</li> -</ul> -<p>Since the config object provided loading of configuration files from -relative filenames we made it possible to change the loading via filenames -to be relative to the instance path if wanted. The behavior of relative -paths in config files can be flipped between “relative to the application -root” (the default) to “relative to instance folder” via the -<cite>instance_relative_config</cite> switch to the application constructor:</p> -<div class="highlight-python"><div class="highlight"><pre><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="n">instance_relative_config</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span> -</pre></div> -</div> -<p>Here is a full example of how to configure Flask to preload the config -from a module and then override the config from a file in the config -folder if it exists:</p> -<div class="highlight-python"><div class="highlight"><pre><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="n">instance_relative_config</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span> -<span class="n">app</span><span class="o">.</span><span class="n">config</span><span class="o">.</span><span class="n">from_object</span><span class="p">(</span><span class="s">'yourapplication.default_settings'</span><span class="p">)</span> -<span class="n">app</span><span class="o">.</span><span class="n">config</span><span class="o">.</span><span class="n">from_pyfile</span><span class="p">(</span><span class="s">'application.cfg'</span><span class="p">,</span> <span class="n">silent</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span> -</pre></div> -</div> -<p>The path to the instance folder can be found via the -<tt class="xref py py-attr docutils literal"><span class="pre">Flask.instance_path</span></tt>. Flask also provides a shortcut to open a -file from the instance folder with <tt class="xref py py-meth docutils literal"><span class="pre">Flask.open_instance_resource()</span></tt>.</p> -<p>Example usage for both:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="n">filename</span> <span class="o">=</span> <span class="n">os</span><span class="o">.</span><span class="n">path</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">app</span><span class="o">.</span><span class="n">instance_root</span><span class="p">,</span> <span class="s">'application.cfg'</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="k">as</span> <span class="n">f</span><span class="p">:</span> - <span class="n">config</span> <span class="o">=</span> <span class="n">f</span><span class="o">.</span><span class="n">read</span><span class="p">()</span> - -<span class="c"># or via open_instance_resource:</span> -<span class="k">with</span> <span class="n">app</span><span class="o">.</span><span class="n">open_instance_resource</span><span class="p">(</span><span class="s">'application.cfg'</span><span class="p">)</span> <span class="k">as</span> <span class="n">f</span><span class="p">:</span> - <span class="n">config</span> <span class="o">=</span> <span class="n">f</span><span class="o">.</span><span class="n">read</span><span class="p">()</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="#">Configuration Handling</a><ul> -<li><a class="reference internal" href="#configuration-basics">Configuration Basics</a></li> -<li><a class="reference internal" href="#builtin-configuration-values">Builtin Configuration Values</a></li> -<li><a class="reference internal" href="#configuring-from-files">Configuring from Files</a></li> -<li><a class="reference internal" href="#configuration-best-practices">Configuration Best Practices</a></li> -<li><a class="reference internal" href="#development-production">Development / Production</a></li> -<li><a class="reference internal" href="#instance-folders">Instance Folders</a></li> -</ul> -</li> -</ul> -<h3>Related Topics</h3> -<ul> - <li><a href="index.html">Documentation overview</a><ul> - <li>Previous: <a href="errorhandling.html" title="previous chapter">Handling Application Errors</a></li> - <li>Next: <a href="signals.html" title="next chapter">Signals</a></li> - </ul></li> -</ul> - <h3>This Page</h3> - <ul class="this-page-menu"> - <li><a href="_sources/config.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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