[refactor] Remove django-weasyprint entirely (#9316)

* Remove django-weasyprint entirely

* Handle null request

* Bug fix

docs/docs/extend/plugins/label.md

@@ -148,7 +148,6 @@ class MyLabelPrinter(LabelPrintingMixin, InvenTreePlugin):
         Send the label to the printer
 
         kwargs:
-            pdf_file: The PDF file object of the rendered label (WeasyTemplateResponse object)
             pdf_data: Raw PDF data of the rendered label
             filename: The filename of this PDF label
             label_instance: The instance of the label model which triggered the print_label() method

src/backend/InvenTree/machine/machine_types/label_printer.py

@@ -141,11 +141,7 @@ class LabelPrinterBaseDriver(BaseDriver):
             label: The LabelTemplate object to render
             item: The item to render the label with
         """
-        return (
+        return self.render_to_pdf(label, item, **kwargs)
-            self.render_to_pdf(label, item, **kwargs)
-            .get_document()  # type: ignore
-            .write_pdf()
-        )
 
     def render_to_html(self, label: LabelTemplate, item: models.Model, **kwargs) -> str:
         """Helper method to render a label to HTML format for a specific item.

src/backend/InvenTree/plugin/base/label/mixins.py

@@ -86,11 +86,7 @@ class LabelPrintingMixin:
         pdf_data = kwargs.get('pdf_data')
 
         if not pdf_data:
-            pdf_data = (
+            pdf_data = self.render_to_pdf(label, instance, request, **kwargs)
-                self.render_to_pdf(label, instance, request, **kwargs)
-                .get_document()
-                .write_pdf()
-            )
 
         pdf2image_kwargs = {
             'dpi': kwargs.get('dpi', InvenTreeSetting.get_setting('LABEL_DPI', 300)),
@@ -152,14 +148,12 @@ class LabelPrintingMixin:
         for item in items:
             context = label.get_context(item, request)
             filename = label.generate_filename(context)
-            pdf_file = self.render_to_pdf(label, item, request, **kwargs)
+            pdf_data = self.render_to_pdf(label, item, request, **kwargs)
-            pdf_data = pdf_file.get_document().write_pdf()
             png_file = self.render_to_png(
                 label, item, request, pdf_data=pdf_data, **kwargs
             )
 
             print_args = {
-                'pdf_file': pdf_file,
                 'pdf_data': pdf_data,
                 'png_file': png_file,
                 'filename': filename,
@@ -179,9 +173,6 @@ class LabelPrintingMixin:
             else:
                 # Offload the print task to the background worker
 
-                # Exclude the 'pdf_file' object - cannot be pickled
-                print_args.pop('pdf_file', None)
-
                 # Exclude the 'context' object - cannot be pickled
                 print_args.pop('context', None)
 
@@ -216,7 +207,6 @@ class LabelPrintingMixin:
         """Print a single label (blocking).
 
         kwargs:
-            pdf_file: The PDF file object of the rendered label (WeasyTemplateResponse object)
             pdf_data: Raw PDF data of the rendered label
             filename: The filename of this PDF label
             label_instance: The instance of the label model which triggered the print_label() method

src/backend/InvenTree/plugin/builtin/labels/inventree_label.py

@@ -1,8 +1,12 @@
 """Default label printing plugin (supports PDF generation)."""
 
+import io
+
 from django.core.files.base import ContentFile
 from django.utils.translation import gettext_lazy as _
 
+from pypdf import PdfWriter
+
 from InvenTree.helpers import str2bool
 from plugin import InvenTreePlugin
 from plugin.mixins import LabelPrintingMixin, SettingsMixin
@@ -50,7 +54,7 @@ class InvenTreeLabelPlugin(LabelPrintingMixin, SettingsMixin, InvenTreePlugin):
             output = self.render_to_html(label, instance, None, **kwargs)
         else:
             # Output is already provided
-            output = kwargs['pdf_file']
+            output = kwargs.get('pdf_data')
 
         self.outputs.append(output)
 
@@ -65,15 +69,17 @@ class InvenTreeLabelPlugin(LabelPrintingMixin, SettingsMixin, InvenTreePlugin):
             filename = 'labels.html'
         else:
             # Stitch together the PDF outputs
-            pages = []
+            pdf_writer = PdfWriter()
 
             for output in self.outputs:
-                doc = output.get_document()
+                output_file = io.BytesIO(output)
+                pdf_writer.append(output_file)
 
-                for page in doc.pages:
+            pdf_file = io.BytesIO()
-                    pages.append(page)
+            pdf_writer.write(pdf_file)
+            data = pdf_file.getvalue()
+            pdf_file.close()
 
-            data = self.outputs[0].get_document().copy(pages).write_pdf()
             filename = kwargs.get('filename', 'labels.pdf')
 
         return ContentFile(data, name=filename)

src/backend/InvenTree/report/models.py

@@ -1,25 +1,24 @@
 """Report template model definitions."""
 
+import io
 import os
 import sys
 
 from django.conf import settings
-from django.contrib.auth.models import AnonymousUser, User
+from django.contrib.auth.models import User
 from django.core.exceptions import ValidationError
 from django.core.files.base import ContentFile
 from django.core.files.storage import default_storage
 from django.core.validators import FileExtensionValidator, MinValueValidator
 from django.db import models
-from django.http import HttpRequest
 from django.template import Context, Template
 from django.template.exceptions import TemplateDoesNotExist
 from django.template.loader import render_to_string
-from django.test.client import RequestFactory
-from django.test.utils import override_settings
 from django.urls import reverse
 from django.utils.translation import gettext_lazy as _
 
 import structlog
+from pypdf import PdfWriter
 
 import InvenTree.exceptions
 import InvenTree.helpers
@@ -33,10 +32,10 @@ from plugin import InvenTreePlugin
 from plugin.registry import registry
 
 try:
-    from django_weasyprint import WeasyTemplateResponseMixin
+    from weasyprint import HTML
 except OSError as err:  # pragma: no cover
     print(f'OSError: {err}')
-    print("Unable to import 'django_weasyprint' module.")
+    print("Unable to import 'weasyprint' module.")
     print('You may require some further system packages to be installed.')
     sys.exit(1)
 
@@ -44,32 +43,6 @@ except OSError as err:  # pragma: no cover
 logger = structlog.getLogger('inventree')
 
 
-MOCK_PRINT_HOST = 'localhost'
-
-
-@override_settings(SITE_URL=MOCK_PRINT_HOST)
-def dummy_print_request() -> HttpRequest:
-    """Generate a dummy HTTP request object.
-
-    - This is required for internal print calls, as WeasyPrint *requires* a request object.
-    - Additionally, we have to mock the HOST header, as WeasyPrint requires a valid HOST URL.
-    """
-    factory = RequestFactory()
-    request = factory.get('/', headers={'host': MOCK_PRINT_HOST})
-    request.user = AnonymousUser()
-    return request
-
-
-class WeasyprintReport(WeasyTemplateResponseMixin):
-    """Class for rendering a HTML template to a PDF."""
-
-    def __init__(self, request, template, **kwargs):
-        """Initialize the report mixin with some standard attributes."""
-        self.request = request
-        self.template_name = template
-        self.pdf_filename = kwargs.get('filename', 'output.pdf')
-
-
 def rename_template(instance, filename):
     """Function to rename a report template once uploaded.
 
@@ -200,33 +173,34 @@ class ReportTemplateBase(MetadataMixin, InvenTree.models.InvenTreeModel):
 
         return template_string.render(Context(context))
 
-    def render_as_string(self, instance, request=None, **kwargs):
+    def render_as_string(self, instance, request=None, **kwargs) -> str:
         """Render the report to a HTML string.
 
-        Useful for debug mode (viewing generated code)
+        Arguments:
+            instance: The model instance to render against
+            request: A HTTPRequest object (optional)
+
+        Returns:
+            str: HTML string
         """
         context = self.get_context(instance, request, **kwargs)
 
         return render_to_string(self.template_name, context, request)
 
-    def render(self, instance, request=None, **kwargs):
+    def render(self, instance, request=None, **kwargs) -> bytes:
         """Render the template to a PDF file.
 
-        Uses django-weasyprint plugin to render HTML template against Weasyprint
+        Arguments:
+            instance: The model instance to render against
+            request: A HTTPRequest object (optional)
+
+        Returns:
+            bytes: PDF data
         """
-        context = self.get_context(instance, request)
+        html = self.render_as_string(instance, request, **kwargs)
+        pdf = HTML(string=html).write_pdf()
 
-        # Render HTML template to PDF
+        return pdf
-        wp = WeasyprintReport(
-            request,
-            self.template_name,
-            base_url=get_base_url(request=request),
-            presentational_hints=True,
-            filename=self.generate_filename(context),
-            **kwargs,
-        )
-
-        return wp.render_to_response(context, **kwargs)
 
     filename_pattern = models.CharField(
         default='output.pdf',
@@ -407,10 +381,6 @@ class ReportTemplate(TemplateUploadMixin, ReportTemplateBase):
         # Start with a default report name
         report_name = None
 
-        if request is None:
-            # Generate a dummy request object
-            request = dummy_print_request()
-
         report_plugins = registry.with_mixin('report')
 
         # If a ReportOutput object is not provided, create a new one
@@ -419,7 +389,7 @@ class ReportTemplate(TemplateUploadMixin, ReportTemplateBase):
                 template=self,
                 items=len(items),
                 user=request.user
-                if request.user and request.user.is_authenticated
+                if request and request.user and request.user.is_authenticated
                 else None,
                 progress=0,
                 complete=False,
@@ -451,12 +421,11 @@ class ReportTemplate(TemplateUploadMixin, ReportTemplateBase):
 
                 # Attach the generated report to the model instance (if required)
                 if self.attach_to_model and not debug_mode:
-                    data = report.get_document().write_pdf()
                     instance.create_attachment(
-                        attachment=ContentFile(data, report_name),
+                        attachment=ContentFile(report, report_name),
                         comment=_(f'Report generated from template {self.name}'),
                         upload_user=request.user
-                        if request.user.is_authenticated
+                        if request and request.user.is_authenticated
                         else None,
                     )
 
@@ -481,7 +450,7 @@ class ReportTemplate(TemplateUploadMixin, ReportTemplateBase):
             raise ValidationError({
                 'error': _('Error generating report'),
                 'detail': str(exc),
-                'path': request.path,
+                'path': request.path if request else None,
             })
 
         if not report_name.endswith('.pdf'):
@@ -492,18 +461,23 @@ class ReportTemplate(TemplateUploadMixin, ReportTemplateBase):
             data = '\n'.join(outputs)
             report_name = report_name.replace('.pdf', '.html')
         else:
-            pages = []
+            # Merge the outputs back together into a single PDF file
+            pdf_writer = PdfWriter()
 
             try:
                 for report in outputs:
-                    doc = report.get_document()
+                    # Construct file object with raw PDF data
-                    for page in doc.pages:
+                    report_file = io.BytesIO(report)
-                        pages.append(page)
+                    pdf_writer.append(report_file)
 
-                data = outputs[0].get_document().copy(pages).write_pdf()
+                # Generate raw output
-            except TemplateDoesNotExist as exc:
+                pdf_file = io.BytesIO()
-                t_name = str(exc) or self.template
+                pdf_writer.write(pdf_file)
-                raise ValidationError(f'Template file {t_name} does not exist')
+                data = pdf_file.getvalue()
+                pdf_file.close()
+            except Exception:
+                InvenTree.exceptions.log_error('report.print')
+                data = None
 
         # Save the generated report to the database
         output.complete = True
@@ -622,7 +596,9 @@ class LabelTemplate(TemplateUploadMixin, ReportTemplateBase):
                 template=self,
                 items=len(items),
                 plugin=plugin.slug,
-                user=request.user if request else None,
+                user=request.user
+                if request and request.user.is_authenticated
+                else None,
                 progress=0,
                 complete=False,
             )
@@ -630,11 +606,6 @@ class LabelTemplate(TemplateUploadMixin, ReportTemplateBase):
         if options is None:
             options = {}
 
-        if request is None:
-            # If the request object is not provided, we need to create a dummy one
-            # Otherwise, WeasyPrint throws an error
-            request = dummy_print_request()
-
         try:
             if hasattr(plugin, 'before_printing'):
                 plugin.before_printing()

src/backend/requirements.in

@@ -26,7 +26,6 @@ django-structlog                        # Structured logging
 django-stdimage                         # Advanced ImageField management
 django-taggit                           # Tagging support
 django-otp==1.3.0                       # Two-factor authentication (legacy to ensure migrations) https://github.com/inventree/InvenTree/pull/6293
-django-weasyprint                       # django weasyprint integration
 djangorestframework<3.15                # DRF framework  # FIXED 2024-06-26 see https://github.com/inventree/InvenTree/pull/7521
 djangorestframework-simplejwt[crypto]   # JWT authentication
 django-xforwardedfor-middleware         # IP forwarding metadata
@@ -40,6 +39,7 @@ pillow                                  # Image manipulation
 pint                                    # Unit conversion
 pip-licenses                            # License information for installed packages
 ppf.datamatrix                          # Data Matrix barcode generator
+pypdf                                   # PDF manipulation tools
 python-barcode[images]                  # Barcode generator
 python-dotenv                           # Environment variable management
 pyyaml>=6.0.1                           # YAML parsing

src/backend/requirements.txt

@@ -411,7 +411,6 @@ django==4.2.20 \
     #   django-stdimage
     #   django-structlog
     #   django-taggit
-    #   django-weasyprint
     #   django-xforwardedfor-middleware
     #   djangorestframework
     #   djangorestframework-simplejwt
@@ -517,10 +516,6 @@ django-taggit==6.1.0 \
     --hash=sha256:ab776264bbc76cb3d7e49e1bf9054962457831bd21c3a42db9138b41956e4cf0 \
     --hash=sha256:c4d1199e6df34125dd36db5eb0efe545b254dec3980ce5dd80e6bab3e78757c3
     # via -r src/backend/requirements.in
-django-weasyprint==2.3.1 \
-    --hash=sha256:09cc1c40c92db34bed80154be7c959fea03d6001dc46fd599f3fd464d6a6dc72 \
-    --hash=sha256:cd35b8bd24b28128a17a2416d0e6f3e64cb727f25c53467150b4be16ccd01c19
-    # via -r src/backend/requirements.in
 django-xforwardedfor-middleware==2.0 \
     --hash=sha256:16fd1cb27f33a5541b6f3e0b43afb1b7334a76f27a1255b69e14ec5c440f0b24
     # via -r src/backend/requirements.in
@@ -1213,6 +1208,10 @@ pyjwt[crypto]==2.10.1 \
     # via
     #   django-allauth
     #   djangorestframework-simplejwt
+pypdf==5.4.0 \
+    --hash=sha256:9af476a9dc30fcb137659b0dec747ea94aa954933c52cf02ee33e39a16fe9175 \
+    --hash=sha256:db994ab47cadc81057ea1591b90e5b543e2b7ef2d0e31ef41a9bfe763c119dab
+    # via -r src/backend/requirements.in
 pyphen==0.17.2 \
     --hash=sha256:3a07fb017cb2341e1d9ff31b8634efb1ae4dc4b130468c7c39dd3d32e7c3affd \
     --hash=sha256:f60647a9c9b30ec6c59910097af82bc5dd2d36576b918e44148d8b07ef3b4aa3
@@ -1626,6 +1625,7 @@ typing-extensions==4.12.2 \
     #   opentelemetry-sdk
     #   pint
     #   py-moneyed
+    #   pypdf
     #   referencing
     #   structlog
 tzdata==2025.1 \
@@ -1652,9 +1652,7 @@ wcwidth==0.2.13 \
 weasyprint==64.1 \
     --hash=sha256:28b02f2c6409bafce1b1220d9d76a7345875bd3bd08c4f6dfbf510bb92a94757 \
     --hash=sha256:f7c88ea8ce0ce0c527cbb9c802689e035fae50016d7efc5dfdaba4b75abf68f4
-    # via
+    # via -r src/backend/requirements.in
-    #   -r src/backend/requirements.in
-    #   django-weasyprint
 webencodings==0.5.1 \
     --hash=sha256:a0af1213f3c2226497a97e2b3aa01a7e4bee4f403f95be16fc9acd2947514a78 \
     --hash=sha256:b36a1c245f2d304965eb4e0a82848379241dc04b865afcc4aab16748587e1923