Detect when a solution has more than 30 pages

apps/participation/forms.py

@@ -3,6 +3,7 @@
 
 import re
 
+from PyPDF3 import PdfFileReader
 from bootstrap_datepicker_plus import DatePickerInput, DateTimePickerInput
 from django import forms
 from django.core.exceptions import ValidationError
@@ -115,6 +116,19 @@ class TournamentForm(forms.ModelForm):
 
 
 class SolutionForm(forms.ModelForm):
+    def clean_file(self):
+        if "file" in self.files:
+            file = self.files["file"]
+            if file.size > 2e6:
+                raise ValidationError(_("The uploaded file size must be under 5 Mo."))
+            if file.content_type != "application/pdf":
+                raise ValidationError(_("The uploaded file must be a PDF file."))
+            pdf_reader = PdfFileReader(file)
+            pages = len(pdf_reader.pages)
+            if pages > 30:
+                raise ValidationError(_("The PDF file must not have more than 30 pages."))
+            return self.cleaned_data["photo_authorization"]
+
     def save(self, commit=True):
         """
         Don't save a solution with this way. Use a view instead