repo_zf1/documentation/manual/en/module_specs/Zend_Tool-Extending.xml

<?xml version="1.0" encoding="UTF-8"?>
<!-- Reviewed: no -->
<sect1 id="zend.tool.extending">
    <title>Extending Zend_Tool</title>

    <sect2 id="zend.tool.extending.overview">
        <title>Overview of Zend_Tool</title>

        <para>
            <classname>Zend_Tool_Framework</classname> is a framework for exposing common
            functionalities such as the creation of project scaffolds, code
            generation, search index generation, and much more. Functionality may be
            written and exposed via <acronym>PHP</acronym> classes dropped into the
            <acronym>PHP</acronym> <property>include_path</property>, providing incredible
            flexibility of implementation. The functionality may then be consumed by writing
            implementation and/or protocol-specific clients -- such as console
            clients, <acronym>XML-RPC</acronym>, <acronym>SOAP</acronym>, and much more.
        </para>

        <para>
            <classname>Zend_Tool_Project</classname> builds on and extends the capabilities of
            <classname>Zend_Tool_Framework</classname> to that of managing a "project". In general, a
            "project" is a planned endeavor or an initiative. In the computer world, projects generally
            are a collection of resources. These resources can be files, directories, databases,
            schemas, images, styles, and more.
        </para>

    </sect2>

    <sect2 id="zend.tool.extending.zend-tool-framework">
        <title>Zend_Tool_Framework Extensions</title>

        <sect3 id="zend.tool.extending.zend-tool-framework.architecture">
            <title>Overall Architecture</title>

            <para>
                <classname>Zend_Tool_Framework</classname> provides the following:
            </para>

            <itemizedlist>
                <listitem>
                    <para>
                        <emphasis>Common interfaces and abstracts</emphasis> that allow
                        developers to create functionality and capabilities that are
                        dispatchable by tooling clients.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <emphasis>Base client functionality</emphasis> and a concrete
                        console implementation that connect external tools and
                        interfaces to the <classname>Zend_Tool_Framework</classname>. The Console
                        client may be used in <acronym>CLI</acronym> environments such as unix shells and
                        the Windows console.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <emphasis>"Provider" and "Manifest" interfaces</emphasis> that
                        can be utilized by the tooling system. "Providers" represent the
                        functional aspect of the framework, and define the actions that
                        tooling clients may call. "Manifests" act as metadata registries
                        that provide additional context for the various defined
                        providers.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <emphasis>An introspective loading system</emphasis> that will
                        scan the environment for providers and determine what is
                        required to dispatch them.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <emphasis>A standard set of system providers</emphasis> that
                        allow the system to report what the full capabilities of the
                        system are as well as provide useful feedback. This also
                        includes a comprehensive "Help System".
                    </para>
                </listitem>
            </itemizedlist>

            <para>
                Definitions that you should be aware of through this manual with respect
                to <classname>Zend_Tool_Framework</classname> include:
            </para>

            <itemizedlist>

                <listitem><para>
                    <classname>Zend_Tool_Framework</classname> - The framework which exposes
                    tooling capabilities.
                </para></listitem>

                <listitem><para>
                    <emphasis>Tooling Client</emphasis> - A developer tool that connects
                    to and consumes <classname>Zend_Tool_Framework</classname>.
                </para></listitem>

                <listitem><para>
                    <emphasis>Client</emphasis> - The subsystem of
                    <classname>Zend_Tool_Framework</classname> that exposes an interface such that
                    tooling clients can connect, query and execute commands.
                </para></listitem>

                <listitem><para>
                    <emphasis>Console Client / Command Line Interface /
                    <filename>zf.php</filename></emphasis> - The tooling client for the command line.
                </para></listitem>

                <listitem><para>
                    <emphasis>Provider</emphasis> - A subsystem and a collection of
                    built-in functionality that the framework exports.
                </para></listitem>

                <listitem><para>
                    <emphasis>Manifest</emphasis> - A subsystem for defining,
                    organizing, and disseminating provider requirement data.
                </para></listitem>

                <listitem><para>
                    <classname>Zend_Tool_Project</classname> Provider - A set of providers
                    specifically for creating and maintaining Zend Framework-based
                    projects.
                </para></listitem>

            </itemizedlist>

        </sect3>

        <sect3 id="zend.tool.extending.zend-tool-framework.cli-client">
            <title>Understanding the CLI Client</title>

            <para>
                The <acronym>CLI</acronym>, or command line tool (internally known as the console tool),
                is currently the primary interface for dispatching <classname>Zend_Tool</classname>
                requests. With the <acronym>CLI</acronym> tool, developers can issue tooling requests
                inside the "command line windows", also commonly known as a "terminal"
                window. This environment is predominant in the *nix environment, but
                also has a common implementation in windows with the
                <filename>cmd.exe</filename>, console2 and also with the Cygwin project.
            </para>

            <sect4 id="zend.tool.extending.zend-tool-framework.cli-client.setup-general">
                <title>Setting up the CLI tool</title>

                <para>
                    To issue tooling requests via the command line client, you first
                    need to set up the client so that your system can handle the "zf"
                    command. The command line client, for all intents and purposes, is
                    the <filename>.sh</filename> or <filename>.bat</filename> file that is provided with
                    your Zend Framework distribution. In trunk, it can be found here:
                    <ulink
                        url="http://framework.zend.com/svn/framework/standard/trunk/bin/">http://framework.zend.com/svn/framework/standard/trunk/bin/</ulink>.
                </para>

                <para>
                    As you can see, there are 3 files in the <filename>/bin/</filename>
                    directory: a <filename>zf.php</filename>, <filename>zf.sh</filename>, and
                    <filename>zf.bat</filename>. The <filename>zf.sh</filename> and the
                    <filename>zf.bat</filename> are the operating system specific client
                    wrappers: <filename>zf.sh</filename> for the *nix environment, and
                    <filename>zf.bat</filename> for the Win32 environment. These client wrappers are
                    responsible for finding the proper <filename>php.exe</filename>, finding the
                    <filename>zf.php</filename>, and passing on the client request. The
                    <filename>zf.php</filename> is the responsible for handling understanding
                    your environment, constructing the proper include_path, and passing
                    what is provided on the command line to the proper library component
                    for dispatching.
                </para>

                <para>
                    Ultimately, you want to ensure two things to make everything work
                    regardless of the operating system you are on:
                </para>

                <orderedlist>
                    <listitem>
                        <para>
                            <filename>zf.sh/zf.bat</filename> is reachable from your system
                            path. This is the ability to call <command>zf</command> from
                            anywhere on your command line, regardless of what your
                            current working directory is.
                        </para>
                    </listitem>
                    <listitem>
                        <para>
                            <filename>ZendFramework/library</filename> is in your
                            <property>include_path</property>.
                        </para>
                    </listitem>
                </orderedlist>

                <note>
                    <para>
                        Note: while the above are the most ideal
                        requirements, you can simply download Zend Framework and expect it
                        to work as <filename>./path/to/zf.php</filename> some command.
                    </para>
                </note>

            </sect4>

            <sect4 id="zend.tool.extending.zend-tool-framework.cli-client.setup-starnix">
                <title>Setting up the CLI tool on Unix-like Systems</title>

                <para>
                    The most common setup in the *nix environment, is to copy the
                    <filename>zf.sh</filename> and <filename>zf.php</filename> into the same directory
                    as your <acronym>PHP</acronym> binary. This can generally be found in one of the
                    following places:
                </para>

                <programlisting language="text"><![CDATA[
/usr/bin
/usr/local/bin
/usr/local/ZendServer/bin/
/Applications/ZendServer/bin/
]]></programlisting>

                <para>
                    To find out the location of your <acronym>PHP</acronym> binary, you can execute 'which
                    php' on the command line. This will return the location of the <acronym>PHP</acronym>
                    binary you will be using to run <acronym>PHP</acronym> scripts in this environment.
                </para>

                <para>
                    The next order of business is to ensure that Zend Framework
                    library is set up correctly inside of the system <acronym>PHP</acronym>
                    <property>include_path</property>. To find out where your
                    <property>include_path</property> is located, you can execute <command>php -i</command>
                    and look for the <property>include_path</property> variable, or more succinctly,
                    execute <command>php -i | grep include_path</command>. Once you have found where
                    your <property>include_path</property> is located (this will generally be
                    something like <filename>/usr/lib/php</filename>, <filename>/usr/share/php</filename>,
                    <filename>/usr/local/lib/php</filename>, or similar), ensure that the contents of the
                    <filename>/library/</filename> directory are put
                    inside your <property>include_path</property> specified directory.
                </para>

                <para>
                    Once you have done those two things, you should be able to issue a
                    command and get back the proper response like this:
                </para>

                <para>
                    <inlinegraphic scale="100" align="center" valign="middle"
                        fileref="figures/zend.tool.framework.cliversionunix.png" format="PNG" />
                </para>

                <para>
                    If you do not see this type of output, go back and check your setup
                    to ensure you have all of the necessary pieces in the proper place.
                </para>

                <para>
                    There are a couple of alternative setups you might want to employ
                    depending on your servers configuration, your level of access, or
                    for other reasons.
                </para>

                <para>
                    <emphasis>Alternative Setup</emphasis> involves keeping the Zend
                    Framework download together as is, and creating a link from a <constant>PATH</constant>
                    location to the <filename>zf.sh</filename>. What this means is you can
                    place the contents of the ZendFramework download into a location
                    such as <filename>/usr/local/share/ZendFramework</filename>, or more locally
                    like <filename>/home/username/lib/ZendFramework</filename>, and creating a
                    symbolic link to the <filename>zf.sh</filename>.
                </para>

                <para>
                    Assuming you want to put the link inside <filename>/usr/local/bin</filename>
                    (this could also work for placing the link inside
                    <filename>/home/username/bin/</filename> for example) you would issue a
                    command similar to this: </para>

                <programlisting language="sh"><![CDATA[
ln -s /usr/local/share/ZendFramework/bin/zf.sh /usr/local/bin/zf

# OR (for example)
ln -s /home/username/lib/ZendFramework/bin/zf.sh /home/username/bin/zf
]]></programlisting>

                <para>
                    This will create a link which you should be able to access globally
                    on the command line.
                </para>

            </sect4>

            <sect4 id="zend.tool.extending.zend-tool-framework.cli-client.setup-windows">
                <title>Setting up the CLI tool on Windows</title>

                <para>
                    The most common setup in the Windows Win32 environment, is to copy
                    the <filename>zf.bat</filename> and <filename>zf.php</filename> into the same
                    directory as your <acronym>PHP</acronym> binary. This can generally be found in one of
                    the following places:
                </para>

                <programlisting language="text"><![CDATA[
C:\PHP
C:\Program Files\ZendServer\bin\
C:\WAMP\PHP\bin
]]></programlisting>

                <para>
                    You should be able to run <filename>php.exe</filename> on the command line.
                    If you are not able to, first check the documentation that came with
                    your <acronym>PHP</acronym> distribution, or ensure that the path to
                    <filename>php.exe</filename> is in your
                    Windows <constant>PATH</constant> environment variable.
                </para>

                <para>
                    The next order of business is to ensure that Zend Framework
                    library is set up correctly inside of the system <acronym>PHP</acronym>
                    <property>include_path</property>. To find out where your
                    <property>include_path</property> is located, you can type <command>php -i</command> and
                    look for the <property>include_path</property> variable, or more succinctly
                    execute <command>php -i | grep include_path</command> if you have Cygwin setup with
                    grep available. Once you have found where your
                    <property>include_path</property> is located (this will generally be
                    something like <filename>C:\PHP\pear</filename>, <filename>C:\PHP\share</filename>,
                    <filename>C:\Program%20Files\ZendServer\share</filename> or similar), ensure
                    that the contents of the library/ directory are put inside your
                    <property>include_path</property> specified directory.
                </para>

                <para>
                    Once you have done those two things, you should be able to issue a
                    command and get back the proper response like this:
                </para>

                <para>
                    <inlinegraphic scale="100" align="center" valign="middle"
                        fileref="figures/zend.tool.framework.cliversionwin32.png" format="PNG" />
                </para>

                <para>
                    If you do not see this type of output, go back and check your setup
                    to ensure you have all of the necessary pieces in the proper place.
                </para>

                <para>
                    There are a couple of alternative setups you might want to employ
                    depending on your server's configuration, your level of access, or
                    for other reasons.
                </para>

                <para>
                    <emphasis>Alternative Setup</emphasis> involves keeping the Zend
                    Framework download together as is, and altering both your system
                    <constant>PATH</constant> as well as the <filename>php.ini</filename> file.
                    In your user's environment, make sure to add
                    <filename>C:\Path\To\ZendFramework\bin</filename>, so that your
                    <filename>zf.bat</filename> file is executable. Also, alter the
                    <filename>php.ini</filename> file to ensure that
                    <filename>C:\Path\To\ZendFramework\library</filename> is in your
                    <property>include_path</property>.
                </para>

            </sect4>

            <sect4 id="zend.tool.extending.zend-tool-framework.cli-client.setup-othernotes">
                <title>Other Setup Considerations</title>

                <para>
                    If for some reason you do not want Zend Framework library inside
                    your <property>include_path</property>, there is another option. There are
                    two special environment variables that <filename>zf.php</filename> will
                    utilize to determine the location of your Zend Framework
                    installation.
                </para>

                <para>
                    The first is <constant>ZEND_TOOL_INCLUDE_PATH_PREPEND</constant>, which will
                    prepend the value of this environment variable to the system
                    (<filename>php.ini</filename>) <property>include_path</property> before loading the
                    client.
                </para>

                <para>
                    Alternatively, you might want to use
                    <constant>ZEND_TOOL_INCLUDE_PATH</constant> to completely
                    <emphasis>replace</emphasis> the system <property>include_path</property>
                    for one that makes sense specifically for the <command>zf</command>
                    command line tool.
                </para>
            </sect4>

        </sect3>

        <sect3 id="zend.tool.extending.zend-tool-framework.providers-and-manifests">
            <title>Creating Providers</title>

            <para>
                In general, a provider, on its own, is nothing more than the shell for a
                developer to bundle up some capabilities they wish to dispatch with the
                command line (or other) clients. It is an analogue to what a
                "controller" is inside of your <acronym>MVC</acronym> application.
            </para>

            <sect4 id="zend.tool.extending.zend-tool-framework.providers-and-manifests.loading">
                <title>How Zend Tool finds your Providers</title>

                <para>
                    By default Zend Tool uses the BasicLoader to find all
                    the providers that you can run. It recursivly iterates all
                    include path directories and opens all files that end
                    with "Manifest.php" or "Provider.php". All classes in these
                    files are inspected if they implement either
                    <classname>Zend_Tool_Framework_Provider_Interface</classname>
                    or <classname>Zend_Tool_Framework_Manifest_ProviderManifestable</classname>.
                    Instances of the provider interface make up for the real functionality
                    and all their public methods are accessible as provider actions.
                    The ProviderManifestable interface however requires the implementation of a method
                    <methodname>getProviders()</methodname> which returns an array of
                    instantiated provider interface instances.
                </para>

                <para>
                    The following naming rules apply on how you can access the providers
                    that were found by the IncludePathLoader:
                </para>

                <itemizedlist>
                    <listitem>
                        <para>
                            The last part of your classname split by underscore is used
                            for the provider name, e.g. "My_Provider_Hello" leads to your
                            provider being accessible by the name "hello".
                        </para>
                    </listitem>
                    <listitem>
                        <para>
                            If your provider has a method <methodname>getName()</methodname>
                            it will be used instead of the previous method to determine
                            the name.
                        </para>
                    </listitem>
                    <listitem>
                        <para>
                            If your provider has "Provider" as prefix, e.g. it is called
                            <classname>My_HelloProvider</classname> it will be stripped
                            from the name so that the provider will be called "hello".
                        </para>
                    </listitem>
                </itemizedlist>

                <note>
                    <para>The IncludePathLoader does not follow symlinks, that means
                    you cannot link provider functionality into your include paths,
                    they have to be physically present in the include paths.</para>
                </note>

                <example id="zend.tool.extending.zend-tool-framework.providers-and-manifests.loading.example">
                    <title>Exposing Your Providers with a Manifest</title>

                    <para>
                        You can expose your providers to Zend Tool by offering a manifest
                        with a special filename ending with "Manifest.php".
                        A Provider Manifest is an implementation of the
                        <interface>Zend_Tool_Framework_Manifest_ProviderManifestable</interface>
                        and requires the <methodname>getProviders()</methodname> method to return
                        an array of instantiated providers. In anticipation of our first
                        own provider <classname>My_Component_HelloProvider</classname>
                        we will create the following manifest:
                    </para>

                    <programlisting language="php"><![CDATA[
class My_Component_Manifest
    implements Zend_Tool_Framework_Manifest_ProviderManifestable
{
    public function getProviders()
    {
        return array(
            new My_Component_HelloProvider()
        );
    }
}
]]></programlisting>

                </example>
            </sect4>

            <sect4 id="zend.tool.extending.zend-tool-framework.providers-and-manifests.basic">
                <title>Basic Instructions for Creating Providers</title>

                <para>
                    As an example, if a developer wants to add the capability of showing
                    the version of a datafile that his 3rd party component is working
                    from, there is only one class the developer would need to implement.
                    Assuming the component is called <classname>My_Component</classname>, he would
                    create a class named <classname>My_Component_HelloProvider</classname> in a
                    file named <filename>HelloProvider.php</filename> somewhere on the
                    <property>include_path</property>. This class would implement
                    <classname>Zend_Tool_Framework_Provider_Interface</classname>, and the body of
                    this file would only have to look like the following:
                </para>

                <programlisting language="php"><![CDATA[
class My_Component_HelloProvider
    implements Zend_Tool_Framework_Provider_Interface
{
    public function say()
    {
        echo 'Hello from my provider!';
    }
}
]]></programlisting>

                <para>
                    Given that code above, and assuming the developer wishes to access
                    this functionality through the console client, the call would look
                    like this:
                </para>

                <programlisting language="sh"><![CDATA[
% zf say hello
Hello from my provider!
]]></programlisting>
            </sect4>

            <sect4 id="zend.tool.extending.zend-tool-framework.providers-and-manifests.response">
                <title>The response object</title>

                <para>
                    As discussed in the architecture section Zend Tool allows to hook different clients for
                    using your Zend Tool providers. To keep compliant with different clients you should
                    use the response object to return messages from your providers instead of using
                    <methodname>echo()</methodname> or a similiar output mechanism. Rewritting our hello
                    provider with this knowledge it looks like:
                </para>

                <programlisting language="php"><![CDATA[
class My_Component_HelloProvider
    extends Zend_Tool_Framework_Provider_Abstract
{
    public function say()
    {
        $this->_registry->getResponse
                        ->appendContent("Hello from my provider!");
    }
}
]]></programlisting>

                <para>
                    As you can see one has to extend the <classname>Zend_Tool_Framework_Provider_Abstract</classname>
                    to gain access to the Registry which holds the <classname>Zend_Tool_Framework_Client_Response</classname>
                    instance.
                </para>
            </sect4>

            <sect4 id="zend.tool.extending.zend-tool-framework.providers-and-manifests.advanced">
                <title>Advanced Development Information</title>

                <sect5 id="zend.tool.extending.zend-tool-framework.providers-and-manifests.advanced.variables">
                    <title>Passing Variables to a Provider</title>

                    <para>
                        The above "Hello World" example is great for simple commands, but
                        what about something more advanced? As your scripting and tooling
                        needs grow, you might find that you need the ability to accept
                        variables. Much like function signatures have parameters, your
                        tooling requests can also accept parameters.
                    </para>

                    <para>
                        Just as each tooling request can be isolated to a method within a
                        class, the parameters of a tooling request can also be isolated in a
                        very well known place. Parameters of the action methods of a
                        provider can include the same parameters you want your client to
                        utilize when calling that provider and action combination. For
                        example, if you wanted to accept a name in the above example, you
                        would probably do this in OO code:
                    </para>

                <programlisting language="php"><![CDATA[
class My_Component_HelloProvider
    implements Zend_Tool_Framework_Provider_Interface
{
    public function say($name = 'Ralph')
    {
        echo 'Hello' . $name . ', from my provider!';
    }
}
]]></programlisting>

                    <para>
                        The above example can then be called via the command line
                        <command>zf say hello Joe</command>. "Joe" will be supplied to the provider as
                        a parameter of the method call. Also note, as you see that the
                        parameter is optional, that means it is also optional on the command
                        line, so that <command>zf say hello</command> will still work, and default
                        to the name "Ralph".
                    </para>

                </sect5>

                <sect5 id="zend.tool.extending.zend-tool-framework.providers-and-manifests.advanced.prompt">
                    <title>Prompt the User for Input</title>

                    <para>
                        There are cases when the workflow of your provider requires
                        to prompt the user for input. This can be done by requesting
                        the client to ask for more the required input by calling:
                    </para>

                    <programlisting language="php"><![CDATA[
class My_Component_HelloProvider
    extends Zend_Tool_Framework_Provider_Abstract
{
    public function say($name = 'Ralph')
    {
        $nameResponse = $this->_registry
                             ->getClient()
                             ->promptInteractiveInput("Whats your name?");
        $name = $name->getContent();

        echo 'Hello' . $name . ', from my provider!';
    }
}
]]></programlisting>

                    <para>
                        This command throws an exception if the current client is not
                        able to handle interactive requests. In case of the default Console Client
                        however you will be asked to enter the name.
                    </para>
                </sect5>

                <sect5 id="zend.tool.extending.zend-tool-framework.providers-and-manifests.advanced.pretendable">
                    <title>Pretending to execute a Provider Action</title>

                    <para>
                        Another interesting feature you might wish to implement is
                        <emphasis>pretendability</emphasis>. Pretendabilty is the ability
                        for your provider to "pretend" as if it is doing the requested
                        action and provider combination and give the user as much
                        information about what it <emphasis>would</emphasis> do without
                        actually doing it. This might be an important notion when doing
                        heavy database or filesystem modifications that the user might not
                        otherwise want to do.
                    </para>

                    <para>
                        Pretendability is easy to implement. There are two parts to this
                        feature: 1) marking the provider as having the ability to "pretend",
                        and 2) checking the request to ensure the current request was indeed
                        asked to be "pretended". This feature is demonstrated in the code
                        sample below.
                    </para>

                    <programlisting language="php"><![CDATA[
class My_Component_HelloProvider
    extends    Zend_Tool_Framework_Provider_Abstract
    implements Zend_Tool_Framework_Provider_Pretendable
{
    public function say($name = 'Ralph')
    {
        if ($this->_registry->getRequest()->isPretend()) {
            echo 'I would say hello to ' . $name . '.';
        } else {
            echo 'Hello' . $name . ', from my provider!';
        }
    }
}
]]></programlisting>

                    <para>
                        To run the provider in pretend mode just call:
                    </para>

                    <programlisting language="sh"><![CDATA[
% zf --pretend say hello Ralph
I would say hello Ralph.
]]></programlisting>

                </sect5>

                <sect5 id="zend.tool.extending.zend-tool-framework.providers-and-manifests.advanced.verbosedebug">
                    <title>Verbose and Debug modes</title>

                    <para>
                        You can also run your provider actions in "verbose" or "debug" modes.
                        The semantics in regard to this actions have to be implemented by you
                        in the context of your provider. You can access debug or verbose modes
                        with:
                    </para>

                    <programlisting language="php"><![CDATA[
class My_Component_HelloProvider
    implements Zend_Tool_Framework_Provider_Interface
{
    public function say($name = 'Ralph')
    {
        if($this->_registry->getRequest()->isVerbose()) {
            echo "Hello::say has been called\n";
        }
        if($this->_registry->getRequest()->isDebug()) {
            syslog(LOG_INFO, "Hello::say has been called\n");
        }
    }
}
]]></programlisting>
                </sect5>

                <sect5 id="zend.tool.extending.zend-tool-framework.providers-and-manifests.advanced.configstorage">
                    <title>Accessing User Config and Storage</title>

                    <para>
                        Using the Enviroment variable <property>ZF_CONFIG_FILE</property> or the
                        .zf.ini in your home directory you can inject configuration parameters into
                        any Zend Tool provider. Access to this configuration is available via the
                        registry that is passed to your provider if you extend
                        <classname>Zend_Tool_Framework_Provider_Abstract</classname>.
                    </para>

                    <programlisting language="php"><![CDATA[
class My_Component_HelloProvider
    extends Zend_Tool_Framework_Provider_Abstract
{
    public function say()
    {
        $username = $this->_registry->getConfig()->username;
        if(!empty($username)) {
            echo "Hello $username!";
        } else {
            echo "Hello!";
        }
    }
}
]]></programlisting>

                    <para>
                        The returned configuration is of the type
                        <classname>Zend_Tool_Framework_Client_Config</classname> but internally the
                        <methodname>__get()</methodname> and <methodname>__set()</methodname> magic methods
                        proxy to a <classname>Zend_Config</classname> of the given configuration type.
                    </para>

                    <para>
                        The storage allows to save arbitrary data for later reference. This can be useful for batch
                        processing tasks or for re-runs of your tasks. You can access the storage in a similar way
                        like the configuration:
                    </para>

                    <programlisting language="php"><![CDATA[
class My_Component_HelloProvider
    extends Zend_Tool_Framework_Provider_Abstract
{
    public function say()
    {
        $aValue = $this->_registry->getStorage()->get("myUsername");
        echo "Hello $aValue!";
    }
}
]]></programlisting>

                    <para>
                        The API of the storage is very simple:
                    </para>

                    <programlisting language="php"><![CDATA[
class Zend_Tool_Framework_Client_Storage
{
    public function setAdapter($adapter);
    public function isEnabled();
    public function put($name, $value);
    public function get($name, $defaultValue=null);
    public function has($name);
    public function remove($name);
    public function getStreamUri($name);
}
]]></programlisting>

                    <important>
                        <para>
                            When designing your providers that are config or storage aware remember to
                            check if the required user-config or storage keys really exist for a user.
                            You won't run into fatal errors when none of these are provided though,
                            since empty ones are created upon request.
                        </para>
                    </important>
                </sect5>

            </sect4>

        </sect3>

    </sect2>

    <sect2 id="zend.tool.extending.zend-tool-project">
        <title>Zend_Tool_Project Extensions</title>

        <para>
            Zend_Tool_Project exposes a rich set of functionality and capabilities that make the task
            of creating new providers, specficially those targetting project easier and more manageable.
        </para>

        <sect3 id="zend.tool.extending.zend-tool-project.architecture">
            <title>Overall Architecture</title>

            <para>
                This same concept applies to Zend Framework projects. In Zend Framework projects, you have
                controllers, actions, views, models, databases and so on and so forth. In terms of
                <classname>Zend_Tool</classname>, we need a way to track these types of resources - thus
                <classname>Zend_Tool_Project</classname>.
            </para>

            <para>
                <classname>Zend_Tool_Project</classname> is capable of tracking project resources throughout
                the development of a project. So, for example, if in one command you created a controller,
                and in the next command you wish to create an action within that controller,
                <classname>Zend_Tool_Project</classname> is gonna have to <emphasis>know</emphasis> about
                the controller file you created so that you can (in the next action), be able to append that
                action to it. This is what keeps our projects up to date and <emphasis>stateful</emphasis>.
            </para>

            <para>
                Another important point to understand about projects is that typically, resources are
                organized in a hierarchical fashion. With that in mind,
                <classname>Zend_Tool_Project</classname> is capable of serializing the current project into
                a internal representation that allows it to keep track of not only <emphasis>what</emphasis>
                resources are part of a project at any given time, but also <emphasis>where</emphasis> they
                are in relation to one another.
            </para>

        </sect3>


        <sect3 id="zend.tool.extending.zend-tool-project.providers">
            <title>Creating Providers</title>

            <para>
                Project specific providers are created in the same fashion as plain framework providers, with
                one exception: project providers must extend the <code>Zend_Tool_Project_Provider_Abstract</code>.
                This class comes with some significant functionality that helps developers load existing project,
                obtian the profile object, and be able to search the profile, then later store any changes to the
                current project profile.
            </para>

            <programlisting language="php"><![CDATA[
class My_Component_HelloProvider
    extends Zend_Tool_Project_Provider_Abstract
{
    public function say()
    {
        $profile = $this->_loadExistingProfile();

        /* ... do project stuff here */

        $this->_storeProfile();
    }
}
]]></programlisting>

        </sect3>

        <!--
        <sect3 id="zend.tool.extending.zend-tool-project.resources-and-contexts">
            <title>Creating Resources &amp; Contexts</title>



        </sect3>
        -->

    </sect2>
</sect1>