======================================================
Snakes on a Bookshelf : MicroPython for Bibliophiles
======================================================

.. todo::

    This article is a work-in-progress.

    In this article, I'll showcase the bookshelf LEDs that I've set up
    for the search engine. I'll not go into too much detail here, since that
    will be part of a series of posts on the Shelfie project.


.. admonition:: Foreword

    My photography skills leave much to be desired. I'll have to retake some
    of these photographs so that I can present this project better.

I am a voracious reader. Unlike most people, I read paragraphs at a glance
when I'm in the mood for it, not lines or words. That helps me read about
500-800 pages in two or three hours.

I've been buying a lot of books, and I read widely and across a varied
set of genres.

I *think* I have 900 books. I am not quite sure. It is hard to count,
sometimes.

.. figure:: ../_static/shelfie/shelf/001.jpg
    :width: 500
    
    I **love** books. I have a lot of them.

.. figure:: ../_static/shelfie/shelf/002.jpg
    :width: 500
    
    I mean, a **lot.**

.. figure:: ../_static/shelfie/shelf/003.jpg
    :width: 500
    
    No really.

.. figure:: ../_static/shelfie/shelf/004.jpg
    :width: 500
    
    **Really.**

.. figure:: ../_static/shelfie/shelf/005.jpg
    :width: 500
    
    You seem to think I'm kidding.

.. figure:: ../_static/shelfie/shelf/006.jpg
    :width: 500
    
    I most definitely **am** not.

.. figure:: ../_static/shelfie/shelf/007.jpg
    :width: 500
    
    So you see, you understand what I mean.

.. figure:: ../_static/shelfie/shelf/008.jpg
    :width: 500
    
    I should count all these, one day.

.. figure:: ../_static/shelfie/shelf/009.jpg
    :width: 500
    
    That day can't come soon enough.

It becomes hard to find books sometimes. Case in point: I own two copies of
several books.

To solve this problem, I decided to blend my love for Python, and my love for
books into one.

I discovered the ESP8266  nodemcu chip a while ago, and it proved to be really
easy to set up. So, using that idea, I decided to look up what I could build
with a couple of them.

This article won't go into the intricacies of the project, because I plan
on describing it further in a series of articles. However, here I plan on
describing my thought process while I was prototyping this project.

---------------------
Call Me Trippy
---------------------

The first step, was sticking a series of WS2812B addressable LED strips
along the sides of the bookshelf. This was a little easier where the top of the
bookshelves were concerned. I was lucky that the total length was *just* under
5m.

I used cellophane tape to secure the strips. I probably should have used
double-sided cellophane tape, but so far, the ordinary tape has secured it in
place.

.. figure:: ../_static/shelfie/bookshelf_leds.jpg
    :width: 500
    
    Step 1: The WS2812B LEDs

---------------------
Hello, MicroPython!
---------------------

Once the LED strips were in place, the first plan of action was to get it
working.

I used the NODEMCU to drive the LED strip. Turns out, I needed a load-shifter
to convert the 3.3V signal from the NODEMCU to 5V required by the LED strip.

.. raw:: html

    <div style="position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; height: auto;">
        <iframe 
            width="860"
            height="520"
            frameborder="0"
            allowfullscreen
            style="position: absolute; top: 0; left: 0; width: 100%; height: 100%;"
            src="https://www.youtube.com/embed/YBYUPO1rMCs">
        </iframe>
    </div>

--------------------
I Like 'em Blues
--------------------

I had to cut and resolder the LED strips for the insides of the bookshelf, a
feat easier said than done, because I'd never touched a solder-iron before.

.. figure:: ../_static/shelfie/inner.jpg
    :width: 500

    The blue light made the bookshelf look rather legit.


--------------------------
What's Capacitance, Doc?
--------------------------

I never really paid attention during Electronics class. So I seemed to have
goofed up where the circuit was concerned.

I seemed to have gotten something wrong with the circuit, and it turns out
that I needed a 100µF capacitor between the inputs to the LED strip.

.. raw:: html

    <div style="position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; height: auto;">
        <iframe 
            width="860"
            height="520"
            frameborder="0"
            allowfullscreen
            style="position: absolute; top: 0; left: 0; width: 100%; height: 100%;"
            src="https://www.youtube.com/embed/_L4kOIKqMhc">
        </iframe>
    </div>

--------------------------------
Let Me Worm My Way Out Of This
--------------------------------

Once half-way there, I could slowly control the timing with a little
precision. That allowed some interesting hijinks.

.. raw:: html

    <div style="position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; height: auto;">
        <iframe 
            width="860"
            height="520"
            frameborder="0"
            allowfullscreen
            style="position: absolute; top: 0; left: 0; width: 100%; height: 100%;"
            src="https://www.youtube.com/embed/5Yx_zzhiu6g">
        </iframe>
    </div>

-----------------------------------
How Long Does This Take?
-----------------------------------

But I kept having the same problems, over and over again. Sometimes, the
circuit worked, and at other times, it did not.

.. raw::

    <div style="position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; height: auto;">
        <iframe 
            width="860"
            height="520"
            frameborder="0"
            allowfullscreen
            style="position: absolute; top: 0; left: 0; width: 100%; height: 100%;"
            src="https://www.youtube.com/embed/wXwPv_sYSIg">
        </iframe>
    </div>

---------------------------
*Et, Voila!*
---------------------------

But once I managed to figure out the circuit's power requirements, I had
*exactly* what I wanted.

.. raw:: html

    <div style="position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; height: auto;">
        <iframe 
            width="860"
            height="520"
            frameborder="0"
            allowfullscreen
            style="position: absolute; top: 0; left: 0; width: 100%; height: 100%;"
            src="https://www.youtube.com/embed/Gjc9Y9n9Y_I">
        </iframe>
    </div>

--------------------------
Next Steps
--------------------------

I need to organize this project better. This is where the *Vial* project
stemmed from, and fulfilling that project will help the realization of the
*Shelfie* project.

--------------------------------------
Shelfie, The Bookshelf Search Engine
--------------------------------------

Shelfie is powered by Raspberry Pis, CouchDB, MicroPython, NodeMCUs,
Flask, Vial, RabbitMQ and the WS2812B LEDs.