return pdf response from stdout with Django

Question

I am using wkhtmltopdf to create PDF files, how ever I don't know how to return them properly, so I had to write them to my media folder and then redirect to the just created file.

Edit: Ian's advice is to write to STDOUT, so I have changed my wkhtmltopdf command to do that, but now I don't know how to return that content.

I have been trying using subprocess.Popen this way:

r = HttpResponse(Popen(command_args), mimetype='application/pdf')
r['Content-Disposition'] = 'filename=recibos.pdf'
return r

But I am not getting good results Thanks in advance.

Answer 1

You should open your sub command like so:

popen = Popen(command_args, stdout=PIPE, stderr=PIPE)
body_contents = popen.stdout().read()
popen.terminate()
popen.wait()
r = HttpResponse(body_contents, mimetype='application/pdf')

Some things to be careful of:

1. If your popen'd command writes to STDERR it may deadlock. You can solve this by using the communicate() function on the Popen object.
2. You should try/finally this to make sure to always terminate() and wait().
3. This loads the whole PDF into the memory of your python process, you may want to stream the bytes from the command to the outgoing socket.