[Zope] ChartDirector and Zope

[Tino Wildenhain]

Am Samstag, den 12.02.2005, 08:06 -0500 schrieb Jonathan Hobbs:
> ----- Original Message -----
> From: <hpinson at indepthl.com>
> > Has anyone gotten the (excellent) ChartDirector charting library to
> > work with zope?
> >
> > Here's what I have tried:
> >
> > 1. Created an ExternalMethod named barchart.py, in the Extensions
> > folder:
> >   #output the chart
> >   print "Content-type: image/png\n"
> >   binaryPrint(c.makeChart2(PNG))
> 
> 
> Where is 'binaryPrint' printing to (a file?  stdio?)?  I am not familiar
> with ChartDirector, but with PIL we have to trick it to write to a 'ram
> file' and then return that, here are the relevant extracts from an external
> method that uses PIL:
> 
> <snip>
> class RamFile:
>                 def __init__(self):
>                         self.contents = []
> 
>                 def write(self,s):
>                         self.contents.append(s)
> 
>                 def read(self):
>                         return string.join(self.contents,'')
> </snip>
> 
> <snip>
> canvas.drawString("S", 7,263, Font(face="times",size=14,bold=1),
> color=black, angle=0)
> canvas.flush()
> rfile = RamFile()
> canvas.save(file=rfile,format="jpeg")
> return rfile.read()
> </snip>

Hm. Wonder why you dont just use cStringIO here?

Tino