Using matplotlib in GAE

Question

My tags and title quite clearly state my problem. I want to use matplotlib to create real-time plots in Google App Engine. I\'ve read the documentation and searched on SO and Go

Answer 1

I'm not familiar with sys module. To give an answer to the question I prefer using webapp2. This is a working handler:

import webapp2
import StringIO
import numpy as np
import matplotlib.pyplot as plt


class MainPage(webapp2.RequestHandler):
    def get(self):
        plt.plot(np.random.random((20)))
        sio = StringIO.StringIO()
        plt.savefig(sio, format="png")
        img_b64 = sio.getvalue().encode("base64").strip()
        plt.clf()
        sio.close()
        self.response.write("""""")
        self.response.write("" % img_b64)
        self.response.write(""" """)

app = webapp2.WSGIApplication([('/', MainPage)], debug=True)

Alternatively, you could write the sio.getvalue() in the blobstore with files api and use the method get_serving_url() of images api for avoid to encode in base64.