InstallerPluginSample
=====================

* :download:`Download example <PyObjCExample-InstallerPluginSample.zip>`

Install plugin sample
=====================

1. What is an Installer Plugin?
-------------------------------

An Installer Plugin extends the user experience of the Installation process by
allowing developers to insert additional custom steps in the installation
process of their software packages.  In the sample code provided here, a
registration pane is built that asks users for registration information before
installing.

Note that informed end-users can remove your package's Plugins directory
and/or change your package's InstallerSections.plist file to remove custom
plugins from its flow. So plugins cannot serve as effective gatekeepers to
prevent installation.

2. Using the Sample Installer Plugin
------------------------------------

1. Take a pre-existing package (or create a new one with PackageMaker.)

   The sample package ``InstallerPluginsTestPackage.pkg`` is provided for your
   test use.

2. Create a ``Plugins`` directory in that Package bundle: ``InstallerPluginsTestPackage.pkg/Contents/Plugins``

3. Run the ``setup.py`` in ``Registration``

4. Copy the created bundle created into the Plugins directory of your package.

5. Copy the ``InstallerSections.plist`` file in this directory into the
   Plugins directory of your package. The ``InstallerSections.plist`` defines
   the order that the Installer section pane will be presented to the user,
   and where the Registration pane will appear (following the ``License`` pane.)

6. Open the package

   It will run with the additional custom Registration plugin (and will ask
   if it is al right to run additional code before opening).

3. Creating Your Own Custom Installer Plugin
--------------------------------------------

Getting started
...............

* Use the provided plugin as your starting point for development.

* Custom Installer Plugins must be written in Cocoa.  They may not be written
  in Carbon or Java, but can be written in Python (obviously).

* Review the InstallerPlugins.framework APIs.

* Copy and update the provided ``InstallerSections.plist`` file to include
  your plugin(s), and place them in the appropriate location in the Install
  sequence.

* Contact the Mac OS X Installation Technology Engineering team with questions
  by subscribing to the installer-dev mailing list (email contact information
  is provided in the 'Notes' section.)

Code Flow in the Plugin
.......................

* The plugin's entry point to is the method ``didEnterPane_(pane)``.

* When the user clicks the "Continue" button, method ``shouldExitPane_(dir)``
  is called. Return False from this method to prevent the user from leaving
  your plugin page.

4. Notes
--------

Plugins are only supported in Mac OS X Tiger (v10.4) and later.

.. lists are no longer a thing:

   Contact: Subscribe to the installer-dev mailing list at the Apple Mailing
   Lists web page <https://lists.apple.com/mailman/listinfo>.  Select the
   "Installer-dev" list item and follow the steps on
   "Subscribing to Installer-dev".

.. dead link:
	Documentation:	http://developer.apple.com/documentation/DeveloperTools/Conceptual/SoftwareDistribution/index.html


.. rst-class:: tabber

Sources
-------

.. rst-class:: tabbertab

setup.py
........

.. sourcecode:: python

    """
    This is dummy file, the real setup.py
    is in ``Registration``
    """

.. rst-class:: tabbertab

Registration/RegistrationPane.py
................................

.. sourcecode:: python

    import Cocoa
    import InstallerPlugins
    import objc
    
    # Important: be aware that informed end-users can remove your package's
    # Plugins directory and/or change your package's InstallerSections.plist file
    # to remove custom plugins from its flow.
    # So plugins cannot serve as effective gatekeepers to prevent installation.
    
    
    class RegistrationPane(InstallerPlugins.InstallerPane):
        uiFirstNameField = objc.IBOutlet()
        uiLastNameField = objc.IBOutlet()
        uiOrganizationField = objc.IBOutlet()
        uiSerialNumberField = objc.IBOutlet()
    
        def _entriesAreValid(self):
            """
            test all textfields to if they all have at least one character in them
            """
            if (
                len(self.uiFirstNameField.stringValue()) == 0
                or len(self.uiLastNameField.stringValue()) == 0
                or len(self.uiOrganizationField.stringValue()) == 0
                or len(self.uiSerialNumberField.stringValue()) == 0
            ):
                return False
    
            return True
    
        def _serialNumberIsValid(self):
            """
            perform a simple string compare to validate the serial number
            entered by the user
            """
            return self.uiSerialNumberField.stringValue() == "123-456-789"
    
        def _updateNextButtonState(self):
            """
            enable the 'Continue' button if '_entriesAreValid' returns 'True'
            """
            self.setNextEnabled_(self._entriesAreValid())
    
        def _localizedStringForKey_(self, key):
            """
            localization helper method:  This pulls localized strings from the
            plugin's bundle
            """
            return Cocoa.NSBundle.bundleForClass_(
                type(self)
            ).localizedStringForKey_value_table_(key, "", None)
    
        def title(self):
            """
            return the title of this pane
            """
            return self._localizedStringForKey_("Title")
    
        def didEnterPane_(self, direction):
            """
            pane's entry point: code called when user enters this pane
            """
            Cocoa.NSLog("DIDENTER")
            self._updateNextButtonState()
    
        def shouldExitPane_(self, direction):
            """
            called when user clicks "Continue" -- return value indicates
            if application should exit pane
            """
            if (
                direction == InstallerPlugins.InstallerDirectionForward
                and not self._serialNumberIsValid()
            ):
                self._updateNextButtonState()
    
                Cocoa.NSBeginInformationalAlertSheet(
                    None,
                    self._localizedStringForKey_("OK_BUTTON"),
                    None,
                    None,
                    self.uiFirstNameField.window(),
                    None,
                    None,
                    None,
                    0,
                    self._localizedStringForKey_("InvalidSerialNumberAlertMessage"),
                )
                return False
    
            return True
    
        def controlTextDidChange_(self, notification):
            """
            updates the state of the next button when the contents of the
            delegate textfields change
            """
            self._updateNextButtonState()

.. rst-class:: tabbertab

Registration/setup.py
.....................

.. sourcecode:: python

    """
    Script for building the example.
    
    Usage:
        python3 setup.py py2app
    """
    from setuptools import setup
    
    plist = {
        "InstallerSectionTitle": "PyRegistration",
        "NSMainNibFile": "Registration",
        "NSPrincipalClass": "InstallerSection",
        "CFBundleIdentifier": "com.MyCompany.Installer.example.Registration",
    }
    
    setup(
        name="Registration",
        plugin=["RegistrationPane.py"],
        data_files=["English.lproj"],
        options={"py2app": {"extension": ".bundle", "plist": plist}},
        setup_requires=[
            "py2app",
            "pyobjc-framework-Cocoa",
            "pyobjc-framework-InstallerPlugins",
        ],
    )

