Install Page
============

It provides user options to install `pip` packages using different methods.
Therefore, three most useful user tasks are implemented :

a)  Install From PyPI
b)  Install From Local Archive
c)  Install From Requirements File
d)  Install From PythonLibs

The GUI options for switching betweeb these pages are provided as a set of
buttons stacked vertically in a tkinter frame. Further options can be added
easily by modifying manage_frame() method.

Install From PyPI Page
----------------------

.. image:: installfrompypi.png

Main components of this page are :

-   Search Bar
        In order to maintain consistency in UI design the search bar is placed
        at top with a search button to it's left. It has been ensured that the
        search bar functions in deafult way i.e. both actions clicking search
        button and pressing <Return> key with focus on tkinter Entry widget
        invoke the `pip` search command.

-   Tree View
        The treeview widget is used to show search results with four fields:
        -   Module Name
        -   Installed Version
        -   Available Versions
        -   Module Summary

        Out of four fields, three fields are shown as row elements of treeview
        widget. On <Double Click>, detailed summary is shown in the below text
        widget. Here, again consistency is maintained as most other package
        managers or installation wizards with GUI function in similar way.

Install From Local Archive
--------------------------

.. image:: installfromlocalarchive.png

It contains an tkinter `entry` widget with a `Browse` button. The `Browse`
button invokes the standard file dialog selection menu. It has been ensured
that file dialog shows archive files so that user can easily choose from
small number of options.

.. Note::
    This page requires improvement as there is empty space available in frame.

Install From Requirements File
------------------------------

The page layout for the Install From Requirements File page is similar to
Install From Local Archive Files.

.. Note::
    This page requires improvement as there is empty space available in frame.

.. toctree::
    :maxdepth: 2

Install From PythonLibs
-----------------------

The functionality to download and install Windows binary from
Pythonlibs (http://www.lfd.uci.edu/~gohlke/pythonlibs/) is provided by this
page. The implementation can be broken down in two parts :

-   Page Layout
        The page layout has options for searching through available Windows
        binaries, installation and sync with backend. The backend is explained
        in next section.

-   Pythonlibs Backend
        For optimum user performance ( that is to provide instant search
        results ), it is necessary to minimize time delay between giving search
        query and recieving search results. Therefore, application maintains
        a local Pythonlibs backend with an option for syncing with latest
        backend available online here:
        `pythonlibs_modules https://github.com/upendra-k14/pythonlibs_modules`_

        The Pythonlibs backend is essentially a json file with crawled metadata
        from Pythonlibs. The crawler is deployed as a cron job to daily crawl
        metadata from Pythonlibs and automatically commit to :
        `pythonlibs_modules https://github.com/upendra-k14/pythonlibs_modules`_

        The crawler code is `here https://github.com/upendra-k14/pip_gui/tree/master/pythonlibscron`_