Initial import of the utils.py file. There is still a lot of work around it,

but this is the core functionality.

Author: Chris Glass

utils.py

@@ -0,0 +1,63 @@
+#-*- coding: utf-8 -*-
+from django.conf import settings
+from django.http import HttpResponse
+from django.template.context import Context
+from django.template.loader import get_template
+from xhtml2pdf import pisa # TODO: Change this when the lib changes.
+import StringIO
+import os
+
+#===============================================================================
+# HELPERS
+#===============================================================================
+class UnsupportedMediaPathException(Exception):
+    pass
+
+def fetch_resources(uri, rel):
+    """
+    Callback to allow xhtml2pdf/reportlab to retrieve Images,Stylesheets, etc.
+    `uri` is the href attribute from the html link element.
+    `rel` gives a relative path, but it's not used here.
+
+    """
+    if uri.startswith(settings.MEDIA_URL):
+        path = os.path.join(settings.MEDIA_ROOT,
+                            uri.replace(settings.MEDIA_URL, ""))
+    elif uri.startswith(settings.STATIC_URL):
+        path = os.path.join(settings.STATIC_ROOT,
+                            uri.replace(settings.STATIC_URL, ""))
+    else:
+        raise UnsupportedMediaPathException(
+                                'media urls must start with %s or %s' % (
+                                settings.MEDIA_ROOT, settings.STATIC_ROOT))
+    return path
+
+def generate_pdf_template_object(template_object, file_object, context):
+    """
+    Inner function to pass template objects directly instead of passing a filename
+    """
+    html = template_object.render(Context(context))
+    pisa.CreatePDF(html.encode("UTF-8"), file_object , encoding='UTF-8',
+                   link_callback=fetch_resources)
+    return file_object
+
+#===============================================================================
+# Main 
+#===============================================================================
+
+def generate_pdf(template_name, file_object=None, context=None): # pragma: no cover
+    """
+    Uses the xhtml2pdf library to render a PDF to the passed file_object, from the
+    given template name.
+    
+    This returns the passed-in file object, filled with the actual PDF data.
+    In case the passed in file object is none, it will return a StringIO instance.
+    
+    """
+    if not file_object:
+        file_object = StringIO.StringIO()
+    if not context:
+        context = {}
+    tmpl = get_template(template_name)
+    generate_pdf_template_object(tmpl, file_object, context)
+    return file_object