diff --git a/docs/outputting_pdf.txt b/docs/outputting_pdf.txt index bd209b2e90..8d72217c75 100644 --- a/docs/outputting_pdf.txt +++ b/docs/outputting_pdf.txt @@ -79,6 +79,15 @@ mention: whatever you want. It'll be used by browsers in the "Save as..." dialogue, etc. + * The ``Content-Disposition`` header starts with ``'attachment; '`` in this + example. This forces Web browsers to pop-up a dialog box + prompting/confirming how to handle the document even if a default is set + on the machine. If you leave off ``'attachment;'``, browsers will handle + the PDF using whatever program/plugin they've been configured to use for + PDFs. Here's what that code would look like:: + + response['Content-Disposition'] = 'filename=somefilename.pdf' + * Hooking into the ReportLab API is easy: Just pass ``response`` as the first argument to ``canvas.Canvas``. The ``Canvas`` class expects a file-like object, and ``HttpResponse`` objects fit the bill. @@ -88,3 +97,56 @@ mention: * Finally, it's important to call ``showPage()`` and ``save()`` on the PDF file. + +Complex PDFs +============ + +If you're creating a complex PDF document with ReportLab, consider using the +cStringIO_ library as a temporary holding place for your PDF file. The +cStringIO library provides a file-like object interface that is particularly +efficient. Here's the above "Hello World" example rewritten to use +``cStringIO``:: + + from cStringIO import StringIO + from reportlab.pdfgen import canvas + from django.utils.httpwrappers import HttpResponse + + def some_view(request): + # Create the HttpResponse object with the appropriate PDF headers. + response = HttpResponse(mimetype='application/pdf') + response['Content-Disposition'] = 'attachment; filename=somefilename.pdf' + + buffer = String() + + # Create the PDF object, using the StringIO object as its "file." + p = canvas.Canvas(buffer) + + # Draw things on the PDF. Here's where the PDF generation happens. + # See the ReportLab documentation for the full list of functionality. + p.drawString(100, 100, "Hello world.") + + # Close the PDF object cleanly. + p.showPage() + p.save() + + # Get the value of the StringIO buffer and write it to the response. + pdf = buffer.getvalue() + buffer.close() + response.write(pdf) + return response + +.. cStringIO: http://www.python.org/doc/current/lib/module-cStringIO.html + +Further resources +================= + + * PDFlib_ is another PDF-generation library that has Python bindings. To + use it with Django, just use the same concepts explained in this article. + * HTMLdoc_ is a command-line script that can convert HTML to PDF. It + doesn't have a Python interface, but you can escape out to the shell + using ``system`` or ``popen`` and retrieve the output in Python. + * `forge_fdf in Python`_ is a library that fills in PDF forms. + +.. _PDFlib: http://www.pdflib.org/ +.. _HTMLdoc: http://www.htmldoc.org/ +.. _forge_fdf in Python: http://www.accesspdf.com/article.php/20050421092951834