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diff --git a/app/static/doc/flask-docs/patterns/fabric.html b/app/static/doc/flask-docs/patterns/fabric.html deleted file mode 100644 index 9949480..0000000 --- a/app/static/doc/flask-docs/patterns/fabric.html +++ /dev/null @@ -1,298 +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>Deploying with Fabric — 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="Using SQLite 3 with Flask" href="sqlite3.html" /> - <link rel="prev" title="Deploying with Distribute" href="distribute.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="sqlite3.html" title="Using SQLite 3 with Flask" - accesskey="N">next</a> |</li> - <li class="right" > - <a href="distribute.html" title="Deploying with Distribute" - 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="deploying-with-fabric"> -<span id="fabric-deployment"></span><h1>Deploying with Fabric<a class="headerlink" href="#deploying-with-fabric" title="Permalink to this headline">¶</a></h1> -<p><a class="reference external" href="http://fabfile.org/">Fabric</a> is a tool for Python similar to Makefiles but with the ability -to execute commands on a remote server. In combination with a properly -set up Python package (<a class="reference internal" href="packages.html#larger-applications"><em>Larger Applications</em></a>) and a good concept for -configurations (<a class="reference internal" href="../config.html#config"><em>Configuration Handling</em></a>) it is very easy to deploy Flask -applications to external servers.</p> -<p>Before we get started, here a quick checklist of things we have to ensure -upfront:</p> -<ul class="simple"> -<li>Fabric 1.0 has to be installed locally. This tutorial assumes the -latest version of Fabric.</li> -<li>The application already has to be a package and requires a working -<cite>setup.py</cite> file (<a class="reference internal" href="distribute.html#distribute-deployment"><em>Deploying with Distribute</em></a>).</li> -<li>In the following example we are using <cite>mod_wsgi</cite> for the remote -servers. You can of course use your own favourite server there, but -for this example we chose Apache + <cite>mod_wsgi</cite> because it’s very easy -to setup and has a simple way to reload applications without root -access.</li> -</ul> -<div class="section" id="creating-the-first-fabfile"> -<h2>Creating the first Fabfile<a class="headerlink" href="#creating-the-first-fabfile" title="Permalink to this headline">¶</a></h2> -<p>A fabfile is what controls what Fabric executes. It is named <cite>fabfile.py</cite> -and executed by the <cite>fab</cite> command. All the functions defined in that file -will show up as <cite>fab</cite> subcommands. They are executed on one or more -hosts. These hosts can be defined either in the fabfile or on the command -line. In this case we will add them to the fabfile.</p> -<p>This is a basic first example that has the ability to upload the current -sourcecode to the server and install it into a pre-existing -virtual environment:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">fabric.api</span> <span class="kn">import</span> <span class="o">*</span> - -<span class="c"># the user to use for the remote commands</span> -<span class="n">env</span><span class="o">.</span><span class="n">user</span> <span class="o">=</span> <span class="s">'appuser'</span> -<span class="c"># the servers where the commands are executed</span> -<span class="n">env</span><span class="o">.</span><span class="n">hosts</span> <span class="o">=</span> <span class="p">[</span><span class="s">'server1.example.com'</span><span class="p">,</span> <span class="s">'server2.example.com'</span><span class="p">]</span> - -<span class="k">def</span> <span class="nf">pack</span><span class="p">():</span> - <span class="c"># create a new source distribution as tarball</span> - <span class="n">local</span><span class="p">(</span><span class="s">'python setup.py sdist --formats=gztar'</span><span class="p">,</span> <span class="n">capture</span><span class="o">=</span><span class="bp">False</span><span class="p">)</span> - -<span class="k">def</span> <span class="nf">deploy</span><span class="p">():</span> - <span class="c"># figure out the release name and version</span> - <span class="n">dist</span> <span class="o">=</span> <span class="n">local</span><span class="p">(</span><span class="s">'python setup.py --fullname'</span><span class="p">,</span> <span class="n">capture</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span><span class="o">.</span><span class="n">strip</span><span class="p">()</span> - <span class="c"># upload the source tarball to the temporary folder on the server</span> - <span class="n">put</span><span class="p">(</span><span class="s">'dist/</span><span class="si">%s</span><span class="s">.tar.gz'</span> <span class="o">%</span> <span class="n">dist</span><span class="p">,</span> <span class="s">'/tmp/yourapplication.tar.gz'</span><span class="p">)</span> - <span class="c"># create a place where we can unzip the tarball, then enter</span> - <span class="c"># that directory and unzip it</span> - <span class="n">run</span><span class="p">(</span><span class="s">'mkdir /tmp/yourapplication'</span><span class="p">)</span> - <span class="k">with</span> <span class="n">cd</span><span class="p">(</span><span class="s">'/tmp/yourapplication'</span><span class="p">):</span> - <span class="n">run</span><span class="p">(</span><span class="s">'tar xzf /tmp/yourapplication.tar.gz'</span><span class="p">)</span> - <span class="c"># now setup the package with our virtual environment's</span> - <span class="c"># python interpreter</span> - <span class="n">run</span><span class="p">(</span><span class="s">'/var/www/yourapplication/env/bin/python setup.py install'</span><span class="p">)</span> - <span class="c"># now that all is set up, delete the folder again</span> - <span class="n">run</span><span class="p">(</span><span class="s">'rm -rf /tmp/yourapplication /tmp/yourapplication.tar.gz'</span><span class="p">)</span> - <span class="c"># and finally touch the .wsgi file so that mod_wsgi triggers</span> - <span class="c"># a reload of the application</span> - <span class="n">run</span><span class="p">(</span><span class="s">'touch /var/www/yourapplication.wsgi'</span><span class="p">)</span> -</pre></div> -</div> -<p>The example above is well documented and should be straightforward. Here -a recap of the most common commands fabric provides:</p> -<ul class="simple"> -<li><cite>run</cite> - executes a command on a remote server</li> -<li><cite>local</cite> - executes a command on the local machine</li> -<li><cite>put</cite> - uploads a file to the remote server</li> -<li><cite>cd</cite> - changes the directory on the serverside. This has to be used -in combination with the <cite>with</cite> statement.</li> -</ul> -</div> -<div class="section" id="running-fabfiles"> -<h2>Running Fabfiles<a class="headerlink" href="#running-fabfiles" title="Permalink to this headline">¶</a></h2> -<p>Now how do you execute that fabfile? You use the <cite>fab</cite> command. To -deploy the current version of the code on the remote server you would use -this command:</p> -<div class="highlight-python"><pre>$ fab pack deploy</pre> -</div> -<p>However this requires that our server already has the -<tt class="docutils literal"><span class="pre">/var/www/yourapplication</span></tt> folder created and -<tt class="docutils literal"><span class="pre">/var/www/yourapplication/env</span></tt> to be a virtual environment. Furthermore -are we not creating the configuration or <cite>.wsgi</cite> file on the server. So -how do we bootstrap a new server into our infrastructure?</p> -<p>This now depends on the number of servers we want to set up. If we just -have one application server (which the majority of applications will -have), creating a command in the fabfile for this is overkill. But -obviously you can do that. In that case you would probably call it -<cite>setup</cite> or <cite>bootstrap</cite> and then pass the servername explicitly on the -command line:</p> -<div class="highlight-python"><pre>$ fab -H newserver.example.com bootstrap</pre> -</div> -<p>To setup a new server you would roughly do these steps:</p> -<ol class="arabic"> -<li><p class="first">Create the directory structure in <tt class="docutils literal"><span class="pre">/var/www</span></tt>:</p> -<div class="highlight-python"><pre>$ mkdir /var/www/yourapplication -$ cd /var/www/yourapplication -$ virtualenv --distribute env</pre> -</div> -</li> -<li><p class="first">Upload a new <cite>application.wsgi</cite> file to the server and the -configuration file for the application (eg: <cite>application.cfg</cite>)</p> -</li> -<li><p class="first">Create a new Apache config for <cite>yourapplication</cite> and activate it. -Make sure to activate watching for changes of the <cite>.wsgi</cite> file so -that we can automatically reload the application by touching it. -(See <a class="reference internal" href="../deploying/mod_wsgi.html#mod-wsgi-deployment"><em>mod_wsgi (Apache)</em></a> for more information)</p> -</li> -</ol> -<p>So now the question is, where do the <cite>application.wsgi</cite> and -<cite>application.cfg</cite> files come from?</p> -</div> -<div class="section" id="the-wsgi-file"> -<h2>The WSGI File<a class="headerlink" href="#the-wsgi-file" title="Permalink to this headline">¶</a></h2> -<p>The WSGI file has to import the application and also to set an environment -variable so that the application knows where to look for the config. This -is a short example that does exactly that:</p> -<div class="highlight-python"><div class="highlight"><pre><span class="kn">import</span> <span class="nn">os</span> -<span class="n">os</span><span class="o">.</span><span class="n">environ</span><span class="p">[</span><span class="s">'YOURAPPLICATION_CONFIG'</span><span class="p">]</span> <span class="o">=</span> <span class="s">'/var/www/yourapplication/application.cfg'</span> -<span class="kn">from</span> <span class="nn">yourapplication</span> <span class="kn">import</span> <span class="n">app</span> -</pre></div> -</div> -<p>The application itself then has to initialize itself like this to look for -the config at that environment variable:</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_config'</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_CONFIG'</span><span class="p">)</span> -</pre></div> -</div> -<p>This approach is explained in detail in the <a class="reference internal" href="../config.html#config"><em>Configuration Handling</em></a> section of the -documentation.</p> -</div> -<div class="section" id="the-configuration-file"> -<h2>The Configuration File<a class="headerlink" href="#the-configuration-file" title="Permalink to this headline">¶</a></h2> -<p>Now as mentioned above, the application will find the correct -configuration file by looking up the <cite>YOURAPPLICATION_CONFIG</cite> environment -variable. So we have to put the configuration in a place where the -application will able to find it. Configuration files have the unfriendly -quality of being different on all computers, so you do not version them -usually.</p> -<p>A popular approach is to store configuration files for different servers -in a separate version control repository and check them out on all -servers. Then symlink the file that is active for the server into the -location where it’s expected (eg: <tt class="docutils literal"><span class="pre">/var/www/yourapplication</span></tt>).</p> -<p>Either way, in our case here we only expect one or two servers and we can -upload them ahead of time by hand.</p> -</div> -<div class="section" id="first-deployment"> -<h2>First Deployment<a class="headerlink" href="#first-deployment" title="Permalink to this headline">¶</a></h2> -<p>Now we can do our first deployment. We have set up the servers so that -they have their virtual environments and activated apache configs. Now we -can pack up the application and deploy it:</p> -<div class="highlight-python"><pre>$ fab pack deploy</pre> -</div> -<p>Fabric will now connect to all servers and run the commands as written -down in the fabfile. First it will execute pack so that we have our -tarball ready and then it will execute deploy and upload the source code -to all servers and install it there. Thanks to the <cite>setup.py</cite> file we -will automatically pull in the required libraries into our virtual -environment.</p> -</div> -<div class="section" id="next-steps"> -<h2>Next Steps<a class="headerlink" href="#next-steps" title="Permalink to this headline">¶</a></h2> -<p>From that point onwards there is so much that can be done to make -deployment actually fun:</p> -<ul class="simple"> -<li>Create a <cite>bootstrap</cite> command that initializes new servers. It could -initialize a new virtual environment, setup apache appropriately etc.</li> -<li>Put configuration files into a separate version control repository -and symlink the active configs into place.</li> -<li>You could also put your application code into a repository and check -out the latest version on the server and then install. That way you -can also easily go back to older versions.</li> -<li>hook in testing functionality so that you can deploy to an external -server and run the testsuite.</li> -</ul> -<p>Working with Fabric is fun and you will notice that it’s quite magical to -type <tt class="docutils literal"><span class="pre">fab</span> <span class="pre">deploy</span></tt> and see your application being deployed automatically -to one or more remote servers.</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="#">Deploying with Fabric</a><ul> -<li><a class="reference internal" href="#creating-the-first-fabfile">Creating the first Fabfile</a></li> -<li><a class="reference internal" href="#running-fabfiles">Running Fabfiles</a></li> -<li><a class="reference internal" href="#the-wsgi-file">The WSGI File</a></li> -<li><a class="reference internal" href="#the-configuration-file">The Configuration File</a></li> -<li><a class="reference internal" href="#first-deployment">First Deployment</a></li> -<li><a class="reference internal" href="#next-steps">Next Steps</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="distribute.html" title="previous chapter">Deploying with Distribute</a></li> - <li>Next: <a href="sqlite3.html" title="next chapter">Using SQLite 3 with Flask</a></li> - </ul></li> - </ul></li> -</ul> - <h3>This Page</h3> - <ul class="this-page-menu"> - <li><a href="../_sources/patterns/fabric.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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