A live data vizualization for development.

http://www.github.com/hildensia/devviz

This is early experimental stuff. Expect it to be buggy.

The idea behind it is that print-debugging is quite convenient very often. But than after a while you have a really cluttered stdout. And parsing it by your eyes doesn't work well after a while. It would be handy to have a tool that reads the stdout for you and makes nice vizualizations of it. This is what devviz should be. Right now it can visualize 1D numerical data as a line plot and a table view. It's basicallly a tracer bullet.

It captures stdout of any programm (via a pipe). If this is in a particular JSON format (right now: if it contains a field called 'value', one called 'name' and one called 'type'), it visualizes it using various views. (euphemisim...)

Technically it consists of three things:

• dcollect.py - A script that reads the output and saves it into a NoSQL database
• redis - The NoSQL database holding the data
• devviz - The actual vizualizer based on flask and bokeh

• flask - The web framework devviz uses
• bokeh - The plotting library used
• redis - The NoSQL database to keep the data

You can install all the python modules (including flask and bokeh) needed by:

$ pip install -r requirements.txt

Look at the redis website how to get redis.

For now we have to start bokeh and redis by hand. It's unconvenient but easy:

$ bokeh-server
$ redis-server

Now you can run devviz:

$ python devviz.py

Open a browser and goto http://localhost:5000. You should see the various views without content. To visualize something try:

$ python scripts/output.py | scripts/dcollect.py

You should see something like:

If you want to visualize your own data, you have to print out a JSON dict with a 'value', a 'name' and a'type' member, prefixed with "dvv: ". E.g.:

import json
x = 0
while True:
    x += 1
    data = {'name': 'cool_var', 'type': 'double', 'value': x}
    print('dvv: {}'.format(json.dumps(data)))

Pipe your output to devviz and your done.

Remember: This is a tracer bullet. It is in a very early stadium. Don't expect it to be useful, cool or anything. But if you like the idea, I'm happy to get issues at github.