pil_progress_bar.py

""" Test for drawing base64 image strings for job progress

Example Job:
{
    'comment': '', 
    'maxslots': 0, 
    'numblocked': 0, 
    'spoolcwd': '/home/freddie/unitard, 
    'numerror': 0, 
    'aftertime': None, 
    'elapsedsecs': 0.0, 
    'owner': 'paul', 
    'spoolhost': 'zanzibar, 
    'spooladdr': '138.72.196.92', 
    'jid': 2680, 
    'service': '', 
    'title': 'Somebody To Render', 
    'numactive': 0, 
    'editpolicy': '', 
    'spooltime': '2014-02-17 08:16:53-08', 
    'projects': [
    'flash_gordon', 
    'hot_space'], 
    'crews': [
    'queen'], 
    'maxcid': 2, 
    'metadata': '', 
    'numready': 0, 
    'tags': [], 
    'afterjids': [], 
    'stoptime': '2014-02-17 08:16:57.971-08', 
    'envkey': [], 
    'tier': '', 
    'etalevel': 1, 
    'numtasks': 2, 
    'numdone': 2, 
    'maxtid': 2, 
    'assignments': '', 
    'spoolfile': '/home/freddie/champion.alf', 
    'esttotalsecs': 0.0, 
    'starttime': '2014-02-17 08:16:53.73-08', 
    'pausetime': None, 
    'minslots': 0, 
    'deletetime': None, 
    'priority': 10.0
}

"""
from collections import OrderedDict
from PIL import Image
import random
import base64
import cStringIO

COLORS = OrderedDict([
    ('numdone', (107,129,140)),
    ('numerror', (204,16,31)),
    ('numactive', (79,224,60)),
    ('numblocked', (242,204,79)),
    ('numready', (3,30,43)),
])

def job_progress(job):
    """ Tractor job object

    Args:
        job (dict): with the following keys:
            numblocked
            numerror
            numactive
            numready
            numtasks
            numdone
    Returns:
        base64 image data
    """
    width = 100
    img = Image.new('RGB', (width, 1))
    pixels = img.load()

    total = sum([job.get(_) for _ in COLORS])

    x = 0
    for attr, color in COLORS.items():
        val = job.get(attr)
        pct = int(float(val)/total * width)
        if val > 0:
            pct = max(1, pct)
        for _ in range(pct):
            pixels[x, 0] = color
            x+=1

    handle = cStringIO.StringIO()
    img.save(handle, format="PNG")
    return base64.b64encode(handle.getvalue())


def main():
    jobs = []
    for i in range(50):
        job = {}
        for attr in COLORS:
            job[attr] = random.randint(0,256)
        jobs.append(job)

    with open('tractor_progress_bars.html', 'w') as fh:
        for job in jobs:
            fh.write("""
        <img src="data:image/png;base64, %s" style='height:1em;width:100px;margin:2px;'/>
        <br/>
        """ % job_progress(job))

if __name__ == '__main__':
    main()