PDFTemplateView.cmd_options contains all the options to pass to wkhtmltopdf

Before, command-line arguments were class-based. Unfortunately, this
means that you cannot add new command-line arguments without
subclassing.

Instead, PDFTemplateView.cmd_options is a dictionary of all
command-line arguments. PDFTemplateView.as_view(cmd_options={...}) now
works as expected.

!!!! WARNING !!!!

cmd_options is now empty, leaving wkhtmltopdf with its default
behaviour. Explicitly add the options you want. Existing subclasses of
PDFTemplateView will now break, but a PendingDeprecationWarning will be
issued. Margins will now be wkhtmltopdf's default of 10mm.

PdfTemplateView contains a compatibility shim with the old default
values for margins and orientation.

3 files changed, 79 insertions, 15 deletions

diff --git a/wkhtmltopdf/tests.py b/wkhtmltopdf/tests.py
index 19fde76..1802440 100644
--- a/wkhtmltopdf/tests.py
+++ b/wkhtmltopdf/tests.py
@@ -218,6 +218,24 @@ class TestViews(TestCase):
             response = view(request)
             self.assertEqual(response.status_code, 405)
 
+    def test_get_cmd_options(self):
+        # Default cmd_options
+        view = PDFTemplateView()
+        self.assertEqual(view.cmd_options, PDFTemplateView.cmd_options)
+        self.assertEqual(PDFTemplateView.cmd_options, {})
+
+        # Instantiate with new cmd_options
+        cmd_options = {'orientation': 'landscape'}
+        view = PDFTemplateView(cmd_options=cmd_options)
+        self.assertEqual(view.cmd_options, cmd_options)
+        self.assertEqual(PDFTemplateView.cmd_options, {})
+
+        # Update local instance of cmd_options
+        view = PDFTemplateView()
+        view.cmd_options.update(cmd_options)
+        self.assertEqual(view.cmd_options, cmd_options)
+        self.assertEqual(PDFTemplateView.cmd_options, {})
+
     def test_deprecated(self):
         """Should warn when using deprecated views."""
         with warnings.catch_warnings(record=True) as w:
@@ -236,3 +254,11 @@ class TestViews(TestCase):
             self.assertTrue(
                 'PDFResponse' in str(w[0].message),
                 "'PDFResponse' not in {!r}".format(w[0].message))
+        with warnings.catch_warnings(record=True) as w:
+            warnings.simplefilter('always')
+            PDFTemplateView().get_pdf_kwargs()
+            self.assertEqual(len(w), 1)
+            self.assertEqual(w[0].category, PendingDeprecationWarning)
+            self.assertTrue(
+                'get_pdf_kwargs()' in str(w[0].message),
+                "'get_pdf_kwargs()' not in {!r}".format(w[0].message))
diff --git a/wkhtmltopdf/utils.py b/wkhtmltopdf/utils.py
index d0475c4..03a5f82 100644
--- a/wkhtmltopdf/utils.py
+++ b/wkhtmltopdf/utils.py
@@ -19,6 +19,8 @@ def _options_to_args(**options):
     flags = []
     for name in sorted(options):
         value = options[name]
+        if value is None:
+            continue
         flags.append('--' + name.replace('_', '-'))
         if value is not True:
             flags.append(unicode(value))
@@ -38,11 +40,17 @@ def wkhtmltopdf(pages, output=None, **kwargs):
                   {'footer_html': 'http://example.com/foot.html'}
               becomes
                   '--footer-html http://example.com/foot.html'
+
               Where there is no value passed, use True. e.g.:
                   {'disable_javascript': True}
               becomes:
                   '--disable-javascript'
 
+              To disable a default option, use None. e.g:
+                  {'quiet': None'}
+              becomes:
+                  ''
+
     example usage:
         wkhtmltopdf(pages=['/tmp/example.html'],
                     dpi=300,
diff --git a/wkhtmltopdf/views.py b/wkhtmltopdf/views.py
index 0e91b2a..bbb6e7d 100644
--- a/wkhtmltopdf/views.py
+++ b/wkhtmltopdf/views.py
@@ -137,14 +137,23 @@ class PDFTemplateView(TemplateView):
     filename = 'rendered_pdf.pdf'
     footer_template = None
     header_template = None
-    orientation = 'portrait'
-    margin_bottom = 0
-    margin_left = 0
-    margin_right = 0
-    margin_top = 0
+
     response_class = PDFTemplateResponse
     html_response_class = TemplateResponse
 
+    # Command-line options to pass to wkhtmltopdf
+    cmd_options = {
+        # 'orientation': 'portrait',
+        # 'collate': True,
+        # 'quiet': None,
+    }
+
+    def __init__(self, *args, **kwargs):
+        super(PDFTemplateView, self).__init__(*args, **kwargs)
+
+        # Copy self.cmd_options to prevent clobbering the class-level object.
+        self.cmd_options = self.cmd_options.copy()
+
     def get(self, request, *args, **kwargs):
         response_class = self.response_class
         try:
@@ -160,15 +169,13 @@ class PDFTemplateView(TemplateView):
     def get_filename(self):
         return self.filename
 
+    def get_cmd_options(self):
+        return self.cmd_options
+
     def get_pdf_kwargs(self):
-        kwargs = {
-            'margin_bottom': self.margin_bottom,
-            'margin_left': self.margin_left,
-            'margin_right': self.margin_right,
-            'margin_top': self.margin_top,
-            'orientation': self.orientation,
-        }
-        return kwargs
+        warnings.warn('PDFTemplateView.get_pdf_kwargs() is deprecated in favour of get_cmd_options(). It will be removed in version 1.',
+                      PendingDeprecationWarning, 2)
+        return self.get_cmd_options()
 
     def get_context_data(self, **kwargs):
         context = super(PDFTemplateView, self).get_context_data(**kwargs)
@@ -185,10 +192,14 @@ class PDFTemplateView(TemplateView):
         """
         Returns a PDF response with a template rendered with the given context.
         """
-        filename = response_kwargs.pop('filename', self.get_filename())
-        cmd_options = response_kwargs.pop('cmd_options', self.get_pdf_kwargs())
+        filename = response_kwargs.pop('filename', None)
+        cmd_options = response_kwargs.pop('cmd_options', None)
 
         if issubclass(self.response_class, PDFTemplateResponse):
+            if filename is None:
+                filename = self.get_filename()
+            if cmd_options is None:
+                cmd_options = self.get_cmd_options()
             return super(PDFTemplateView, self).render_to_response(
                 context=context, filename=filename, cmd_options=cmd_options,
                 **response_kwargs
@@ -201,7 +212,26 @@ class PDFTemplateView(TemplateView):
 
 
 class PdfTemplateView(PDFTemplateView): #TODO: Remove this in v1.0
+    orientation = 'portrait'
+    margin_bottom = 0
+    margin_left = 0
+    margin_right = 0
+    margin_top = 0
+
     def __init__(self, *args, **kwargs):
         warnings.warn('PdfTemplateView is deprecated in favour of PDFTemplateView. It will be removed in version 1.',
                       PendingDeprecationWarning, 2)
         super(PdfTemplateView, self).__init__(*args, **kwargs)
+
+    def get_cmd_options(self):
+        return self.get_pdf_kwargs()
+
+    def get_pdf_kwargs(self):
+        kwargs = {
+            'margin_bottom': self.margin_bottom,
+            'margin_left': self.margin_left,
+            'margin_right': self.margin_right,
+            'margin_top': self.margin_top,
+            'orientation': self.orientation,
+        }
+        return kwargs