testing fix

course_selection/pdf.py

@@ -1,76 +1,112 @@
-# retrieved from: https://gist.github.com/zyegfryed/918403
+# retrieved from: https://gist.github.com/zyegfryed/918403, https://gist.github.com/grantmcconnaughey/ce90a689050c07c61c96
 # used for creating pdf files to be served using django
 
 # -*- coding: utf-8 -*-
 import codecs
 import subprocess
 from fdfgen import forge_fdf
+from django.core.exceptions import ImproperlyConfigured
+from django.template import engines
+from django.template.backends.base import BaseEngine
+from django.template.engine import Engine, _dirs_undefined
 
-from django.template import Template, loader
-from django.template.loader import get_template as gtl, LoaderOrigin
 
 
 class PdfTemplateError(Exception):
     pass
 
+class PdftkEngine(BaseEngine):
 
-class PdfTemplate(Template):
+    # Going ahead and defining this, but really PDFs should still be placed
+    # in the templates directory of an app because the loader checks templates
+    app_dirname = 'pdfs'
 
-    def __init__(self, template_string, origin=None, name='<Unknown Template>'):
-        self.origin = origin
+    def __init__(self, params):
+        params = params.copy()
+        options = params.pop('OPTIONS').copy()
+        super(PdftkEngine, self).__init__(params)
+        self.engine = self._Engine(self.dirs, self.app_dirs, **options)
+
+    def get_template(self, template_name, dirs=_dirs_undefined):
+        return PdfTemplate(self.engine.get_template(template_name, dirs))
+
+    class _Engine(Engine):
+        def make_origin(self, display_name, loader, name, dirs):
+            # Always return an Origin object, because PDFTemplate need it to
+            # render the PDF Form file.
+            from django.template.loader import LoaderOrigin
+            return LoaderOrigin(display_name, loader, name, dirs)
+
+
+class PdfTemplate(object):
+    pdftk_bin = None
+
+    def __init__(self, template):
+        self.template = template
+        self.set_pdftk_bin()
+
+    @property
+    def origin(self):
+        return self.template.origin
+
+    def render(self, context=None, request=None):
+        if context is None:
+            context = {}
 
-    def render(self, context):
         context = context.items()
         output, err = self.fill_form(context, self.origin.name)
         if err:
             raise PdfTemplateError(err)
         return output
 
     def fill_form(self, fields, src, pdftk_bin=None):
-        if pdftk_bin is None:
-            from django.conf import settings
-            assert hasattr(settings, 'PDFTK_BIN'), "PDF generation requires pdftk (http://www.pdflabs.com/tools/pdftk-the-pdf-toolkit/). Edit your PDFTK_BIN settings accordingly."
-            assert len(settings.PDFTK_BIN) > 0
-            pdftk_bin = settings.PDFTK_BIN
-
         fdf_stream = forge_fdf(fdf_data_strings=fields)
 
-        cmd = [
-            pdftk_bin,
-            src,
-            'fill_form',
-            '-',
-            'output',
-            '-',
-            'flatten',
-        ]
+        cmd = [self.pdftk_bin, src, 'fill_form', '-', 'output', '-', 'flatten']
+        cmd = ' '.join(cmd)
+
+        return self.run_cmd(cmd, fdf_stream)
+
+    def dump_data_fields(self):
+        cmd = [self.pdftk_bin, self.origin.name, 'dump_data_fields']
         cmd = ' '.join(cmd)
 
+        output, err = self.run_cmd(cmd, None)
+        if err:
+            raise PdfTemplateError(err)
+        return output
+
+    def run_cmd(self, cmd, input_data):
         try:
             process = subprocess.Popen(cmd, stdin=subprocess.PIPE,
                                        stdout=subprocess.PIPE, shell=True)
-            return process.communicate(input=fdf_stream)
-        except OSError:
-            return None
-
-
-def get_template_from_string(source, origin=None, name=None):
-    """
-    Returns a compiled Template object for the given template code,
-    handling template inheritance recursively.
-    """
-    if name and name.endswith('.pdf'):
-        return PdfTemplate('pdf', origin, name)
-    return Template(source, origin, name)
-loader.get_template_from_string = get_template_from_string
+            if input_data:
+                return process.communicate(input=input_data)
+            else:
+                return process.communicate()
+        except OSError, e:
+            return None, e
+
+    def set_pdftk_bin(self):
+        if self.pdftk_bin is None:
+            from django.conf import settings
+            if not hasattr(settings, 'PDFTK_BIN'):
+                msg = "PDF generation requires pdftk " \
+                      "(http://www.pdflabs.com/tools/pdftk-the-pdf-toolkit). " \
+                      "Edit your PDFTK_BIN settings accordingly."
+                raise ImproperlyConfigured(msg)
+            self.pdftk_bin = settings.PDFTK_BIN
 
+        return self.pdftk_bin
 
-def make_origin(display_name, loader, name, dirs):
-    # Always return an Origin object, because PDFTemplate need it to render
-    # the PDF Form file.
-    return LoaderOrigin(display_name, loader, name, dirs)
-loader.make_origin = make_origin
+    def version(self):
+        cmd = [self.pdftk_bin, '--version']
+        cmd = ' '.join(cmd)
 
+        output, err = self.run_cmd(cmd, None)
+        if err:
+            raise PdfTemplateError(err)
+        return output
 
 def get_template(template_name):
     """
@@ -87,9 +123,13 @@ def fake_strict_errors(exception):
     # Loading hacks
     # Ignore UnicodeError, due to PDF file read
     codecs.register_error('strict', fake_strict_errors)
-    # --//--
-    template = gtl(template_name)
+
+    if template_name.endswith('.pdf'):
+        template = engines['pdf'].get_template(template_name)
+    else:
+        template = engines['django'].get_template(template_name)
+
     # Loading hacks
     codecs.register_error('strict', strict_errors)
-    # --//--
-    return template
+
+    return template

course_selection/views.py

@@ -215,8 +215,8 @@ def mobile_logged_in(request):
 # course enrollment form generation
 #############################################################################
 
+from pdf import get_template
 def get_worksheet_pdf(request, schedule_id, template_name='course_enrollment_worksheet.pdf', **kwargs):
-    from pdf import get_template
 
     """
     returns a filled out course enrollment form

settings/common.py

@@ -131,6 +131,18 @@
 TEMPLATE_DIRS = [normpath(join(DJANGO_ROOT, 'course_selection', 'templates')),
                  ]
 
+TEMPLATES = [
+    {
+        'BACKEND': 'django.template.backends.django.DjangoTemplates',
+        'APP_DIRS': True,
+    },
+    {
+        'BACKEND': 'course_selection.pdf.PdftkEngine',
+        'APP_DIRS': True,
+    },
+]
+
+
 CACHES = {
     'default': {
         'BACKEND': 'django.core.cache.backends.dummy.DummyCache',  # overwritten in prod.py