Google Directions API, Part 2
=============================


Contents
--------

.. toctree::
   :maxdepth: 1


Indices and tables
------------------

* :ref:`genindex`
* :ref:`modindex`
* :ref:`search`


Exercise
--------

For this week, the goal is to implement a function that does the following:

* The function should accept 3 parameters, which you parsed with the argument parsing function last week:
    
    * Starting location
   
    * Destination location
    
    * Trip waypoints: None or List

* Sends an http request to the `Google Directions API <https://developers.google.com/maps/documentation/directions/>`_ 
    
    * Full information on how to construct a link can be found at the API site (note: an API key is not actually required), but here are some guidelines:
        
        * Use `http://maps.googleapis.com/maps/api/directions/json?` as the base of the query. Http works best for python and we want json output. 
        
        * Options are added as name=value, with & joining multiple options together. Start = "origin", End = "destination", Waypoints = "waypoints"
        
        * `Here is a sample query to illistrate <http://maps.googleapis.com/maps/api/directions/json?origin=649+North+service+Road,+Burlington,+ON&destination=Niagara+Falls,+ON&waypoints=Tim+Hortons+Field,+Hamilton,+ON|>`_
        
* Return the json result.


This excercise will require use of the :py:mod:`requests` package, specifically :py:mod:`requests.get`

For exceptions look at :py:exc:`requests.ConnectionError` and :py:exc:`requests.Timeout`

Requests should be installed now, if not try 

.. code-block:: bash

   $ sudo -H pip3 install -U requests
   


On completion of this exercies, you should be able to run your stub program and have it do the following:

* Parse the arguments as outlined last week

* Print the query result with just a start and end point passed.

* Print the query result with start, end, and one or more waypoints passed.


Note: you might receive a response from the API about being over your allotted number of requests. If this happens, just try again.

Hints
-----

To help you get started, here is one possible signature for the request function:

.. literalinclude:: directions2.py
   :language: python3
   :lines: 60-67
   
* Use exception handling as appropriate.

Solution
--------

When you are ready to see one possible solution, try :download:`this file <directions2.py>`