Fix PDF on Django 1.11 (#577)

* Fix migration 0043_...

* Use a xhtml2pdf version that is compatible with django 1.8 and 1.11

* Add git to dockerfile in order to install xhtml2pdf

* Pin a released version of xhtml2pdf

* Bump version 0.4.2

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 0.4.1 (2017-11-16)
+- Remove django-xhtml2pdf
+- Adapt pdf generation for Django 1.8 and 1.11
+
 ## 0.4.1 (2017-11-15)
 Add deleted customer and id filters on document list endpoint.
 

requirements/common.txt

@@ -15,13 +15,14 @@ django-model-utils
 django-annoying
 pytz
 PyJWT
+
 # python-dev is required for xhtml2pdf to work
-xhtml2pdf
-django-xhtml2pdf
+xhtml2pdf==0.2b1
+
 pyvat
 PyPDF2
 furl
-html5lib==0.999
+
 cryptography==1.9
 sqlparse==0.2.2
 django-autocomplete-light==3.2.9

settings.py

@@ -55,7 +55,6 @@
     'django_fsm',
     'rest_framework',
     'django_filters',
-    'django_xhtml2pdf',
 
     # Dev tools
     # 'django_extensions',

setup.py

@@ -60,7 +60,7 @@ def read(fname):
 
 setup(
     name="django-silver",
-    version='0.4.1',
+    version='0.4.2',
     description=read('DESCRIPTION'),
     long_description=read('README.rst'),
     license='Apache 2.0',

silver/migrations/0043_auto_20171113_1048.py

@@ -309,3 +309,4 @@ class Migration(migrations.Migration):
             reverse_sql=""
         )
     ]
+

silver/models/documents/pdf.py

@@ -1,6 +1,6 @@
 import uuid
 
-from django_xhtml2pdf.utils import generate_pdf_template_object
+from xhtml2pdf import pisa
 
 from django.conf import settings
 from django.core.files.base import ContentFile
@@ -9,6 +9,8 @@
 from django.http import HttpResponse
 from django.utils.module_loading import import_string
 
+from silver.utils.pdf import fetch_resources
+
 
 def get_storage():
     storage_settings = getattr(settings, 'SILVER_DOCUMENT_STORAGE', None)
@@ -37,7 +39,11 @@ def url(self):
     def generate(self, template, context, upload=True):
         pdf_file_object = HttpResponse(content_type='application/pdf')
 
-        generate_pdf_template_object(template, pdf_file_object, context)
+        html = template.render(context)
+        pisa.pisaDocument(src=html.encode("UTF-8"),
+                          dest=pdf_file_object,
+                          encoding='UTF-8',
+                          link_callback=fetch_resources)
 
         if not pdf_file_object:
             return

silver/tests/tasks/test_generate_pdfs.py

@@ -4,6 +4,8 @@
 from silver.tasks import generate_pdfs, generate_pdf
 from silver.tests.factories import InvoiceFactory, ProformaFactory
 
+from silver.utils.pdf import fetch_resources
+
 
 @pytest.mark.django_db
 def test_generate_pdfs_task(monkeypatch):
@@ -47,18 +49,21 @@ def test_generate_pdfs_task(monkeypatch):
 
 
 @pytest.mark.django_db
-def test_generate_pdf_task(settings, tmpdir, monkeypatch):
+@patch('silver.models.documents.base.BillingDocumentBase.get_template')
+@patch('silver.models.documents.pdf.HttpResponse')
+def test_generate_pdf_task(mock_http_response, mock_get_template, settings,
+                           tmpdir, monkeypatch):
     settings.MEDIA_ROOT = tmpdir.strpath
 
     invoice = InvoiceFactory.create()
     invoice.issue()
 
     assert invoice.pdf.dirty
 
-    generate_pdf_mock = MagicMock()
+    pisa_document_mock = MagicMock()
 
-    monkeypatch.setattr('silver.models.documents.pdf.generate_pdf_template_object',
-                        generate_pdf_mock)
+    monkeypatch.setattr('silver.models.documents.pdf.pisa.pisaDocument',
+                        pisa_document_mock)
 
     generate_pdf(invoice.id, invoice.kind)
 
@@ -70,4 +75,8 @@ def test_generate_pdf_task(settings, tmpdir, monkeypatch):
 
     assert invoice.pdf.url == settings.MEDIA_URL + invoice.get_pdf_upload_path()
 
-    assert generate_pdf_mock.call_count == 1
+    assert pisa_document_mock.call_count == 1
+    pisa_document_mock.assert_called_once_with(src=mock_get_template().render().encode('UTF-8'),
+                                               dest=mock_http_response(),
+                                               encoding='UTF-8',
+                                               link_callback=fetch_resources)

silver/utils/pdf.py

@@ -0,0 +1,33 @@
+import os
+
+from django.conf import settings
+
+
+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 settings.MEDIA_URL and uri.startswith(settings.MEDIA_URL):
+        path = os.path.join(settings.MEDIA_ROOT,
+                            uri.replace(settings.MEDIA_URL, ""))
+    elif settings.STATIC_URL and uri.startswith(settings.STATIC_URL):
+        path = os.path.join(settings.STATIC_ROOT,
+                            uri.replace(settings.STATIC_URL, ""))
+        if not os.path.exists(path):
+            for d in settings.STATICFILES_DIRS:
+                path = os.path.join(d, uri.replace(settings.STATIC_URL, ""))
+                if os.path.exists(path):
+                    break
+    elif uri.startswith("http://") or uri.startswith("https://"):
+        path = uri
+    else:
+        raise UnsupportedMediaPathException('media urls must start with %s or %s' % (
+            settings.MEDIA_URL, settings.STATIC_URL))
+
+    return path