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    <p>I assume your configurations builds a tree with nodes beings sections and leaf being configuration options.</p> <p>Given that setup you can represent a 2 depth deep configuration like network with the following classes using a declarative API:</p> <pre><code>class InterfaceConfiguration(Configuration): mask = IPField() dns = IPField() IP = IPField() dhcp = BooleanField() driver = ChoiceField(choices=('madwifi', 'atheros', 'whatever')) class NetworkConfiguration(Configuration): eth0 = InterfaceConfiguration(verbose_name='network interface eth0') eth1 = InterfaceConfiguration(verbose_name='network interface eth1') wlan0 = InterfaceConfiguration(verboxe_name='wireless network interface wlan0') hostname = StringField() domain = StringField() </code></pre> <p>This kind of declarative API is achieved with <a href="https://stackoverflow.com/questions/100003/what-is-a-metaclass-in-python">metaclasses</a> have a look at <a href="https://github.com/j2labs/dictshield/blob/master/dictshield/document.py" rel="nofollow noreferrer">dictshield</a>, and the <a href="http://code.google.com/p/appengine-ndb-experiment/source/browse/ndb/model.py#2151" rel="nofollow noreferrer">many</a> <a href="https://bitbucket.org/zzzeek/sqlalchemy/src/f2c79e9a0bde/lib/sqlalchemy/ext/declarative.py" rel="nofollow noreferrer">ORMs</a> and <a href="https://bitbucket.org/abki/graffiti/src/2280f7f39328/graffiti/elements.py" rel="nofollow noreferrer">more</a> that implements such feature.</p> <p>Given this set of class you would be able to manipulate them as follow:</p> <pre><code>&gt;&gt;&gt; configuration = NetworkConfiguration('/path/to/config/file') &gt;&gt;&gt; configuration.eth0.verbose_name 'network interface eth0' &gt;&gt;&gt; configuration.eth0.mask.set('192.168.0.255') True &gt;&gt;&gt; configuration.eth0.driver.choices ('madwifi', 'atheros', 'whatever') &gt;&gt;&gt; configuration.hostname.set('amokrane') &gt;&gt;&gt; configuration.domain.set('imazighen') &gt;&gt;&gt; configuration.wlan0.dhcp.get_value() True </code></pre> <p>This kind of API is simpler to implement and doesn't require specific python construction (see below) and provide the ability to have other methods besides get and set.</p> <p>If you don't need other methods besides get/set you can use python descriptors to implement the different kind of fields, I recommand you read the article <a href="http://www.cafepy.com/article/python_attributes_and_methods/python_attributes_and_methods.html" rel="nofollow noreferrer">Python attributes and methods</a> about the subject and have deeper looks and the above links about Python ORMs since that is the used method.</p>
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    1. POClasses to group some actions in Python
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    1. COI like Your idea, but I need to read/write these values from system. For example NetworkConfiguration should be able to read/write interfaces from /etc/network/interfaces file (in Ubuntu). I am not sure if simply write read/write methods in Configuration and reimplement them in every subclass? Second I am not sure if hostname should belong to NetworkConfiguration class too because this is stored in another file...
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    2. CO1) I took the exemple of a network configuration where one file controls every aspects of network configuration, to show how it can be implemented. Describe a complex configuration that you need implemented I will update the exemple in consequence
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    3. COwrite/read are handled by the base classes via introspection, so you never actually write new code to implement new configurations files. But you might write new code if you want to support new Field types.
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