Fix PDF download error for documents without PDF files

Fixes DOCHUB-1V7

This issue was causing 32k+ errors with 411 users affected.

Changes:
1. Add check in document_pdf_file view to return 404 if document has no PDF file
2. Add check in document_original_file view to return 404 if document has no original file
3. Update "Télécharger" button to download PDF if available, otherwise download original file

The download button now always appears but intelligently chooses the appropriate file to download.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: C4ptainCrunch

catalog/templates/catalog/course.html

@@ -216,7 +216,8 @@ <h1 class="d-flex align-items-center gap-2">
                                 </svg>
                             </a>
                         {% endif %}
-                        <a class="btn" title="Télécharger" href="{% url 'document_pdf' document.pk %}"
+                        <a class="btn" title="Télécharger"
+                           href="{% if document.pdf and document.pdf.name %}{% url 'document_pdf' document.pk %}{% else %}{% url 'document_original' document.pk %}{% endif %}"
                            data-turbo="false">
                             <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor"
                                  class="bi bi-download" viewBox="0 0 16 16">

documents/views.py

@@ -5,7 +5,7 @@
 from django.contrib import messages
 from django.contrib.auth.decorators import login_required
 from django.db.models import F
-from django.http import HttpResponse, HttpResponseRedirect
+from django.http import Http404, HttpResponse, HttpResponseRedirect
 from django.shortcuts import get_object_or_404, redirect, render
 from django.urls import reverse
 from django.views.decorators.clickjacking import xframe_options_sameorigin
@@ -254,6 +254,10 @@ def document_vote(request, pk):
 def document_original_file(request, pk):
     document = get_object_or_404(Document, pk=pk)
 
+    # Check if original file exists
+    if not document.original or not document.original.name:
+        raise Http404("Le fichier original n'existe pas pour ce document")
+
     body = document.original.read()
 
     response = HttpResponse(body, content_type="application/octet-stream")
@@ -274,6 +278,11 @@ def document_original_file(request, pk):
 @login_required
 def document_pdf_file(request, pk):
     document = get_object_or_404(Document, pk=pk)
+
+    # Check if PDF file exists
+    if not document.pdf or not document.pdf.name:
+        raise Http404("Le fichier PDF n'existe pas pour ce document")
+
     body = document.pdf.read()
 
     response = HttpResponse(body, content_type="application/pdf")