Google Calendar MultiMerge
==========================
Programmed and designed by Matti 'ccr' Hämäläinen <ccr@tnsp.org>
(C) Copyright 2016 Tecnic Software productions (TNSP)

For license information, see file "COPYING".

Introduction
============

Google Calendar Multimerge (GCMM) is a simple Python utility for
creating a "merged" calendar from a number of "source" calendars.
Through Google Calendar API, events are copied from source calendars
to the target calendar and updated on each run. Deleted events will
be accordingly deleted from the target.

In practice, the target is always an amalgamate of the sources, if
any events are added or deleted from it manually, they will be deleted
or re-added accordingly from it on the next run of GCMM.

The reason for GCMM is that while an amalgamate view of all calendars
(shared or not) can be viewed through the main calendar site, the
amalgamate view can't be shared or viewed as an embedded element
directly.


How to use
==========

First, we need to install the required Python tools in order to
install the required Google API Python modules ... in Debian/Ubuntu,
chant the following magic incantations:

$ sudo apt-get install python-pip python-setuptools python-wheel

Then, use PIP to install Google API stuff locally for the user ..

$ pip install --upgrade google-api-python-client

--

At this point, you will need to enable the Calendar API from
Google's control panel. Refer to the following web page:

https://developers.google.com/google-apps/calendar/quickstart/python

The section "Step 1" has the instructions. We've already done "Step 2",
which is incomplete in the guide anyway.

--

Finally, edit example.cfg and run multimerge with config file as
command line parameter (if no configuration file is specified,
certain default settings will be used):

$ ./multimerge.py example.cfg

On first run, you will need to authenticate Multimerge to allow
access to the target calendar. You copy & paste the generated URL
to browser, authenticate and copy & paste the given "key" to
the Multimerge's prompt and hit ENTER.

After first time authentication the program can be run from a
Cron task, if preferred.