Feature: page count (#7750)

---------

Co-authored-by: shamoon <4887959+shamoon@users.noreply.github.com>

src/documents/tests/test_migration_document_pages_count.py

@@ -0,0 +1,59 @@
+import os
+import shutil
+from pathlib import Path
+
+from django.conf import settings
+
+from documents.tests.utils import TestMigrations
+
+
+def source_path_before(self):
+    if self.filename:
+        fname = str(self.filename)
+
+    return os.path.join(settings.ORIGINALS_DIR, fname)
+
+
+class TestMigrateDocumentPageCount(TestMigrations):
+    migrate_from = "1052_document_transaction_id"
+    migrate_to = "1053_document_page_count"
+
+    def setUpBeforeMigration(self, apps):
+        Document = apps.get_model("documents", "Document")
+        doc = Document.objects.create(
+            title="test1",
+            mime_type="application/pdf",
+            filename="file1.pdf",
+        )
+        self.doc_id = doc.id
+        shutil.copy(
+            Path(__file__).parent / "samples" / "simple.pdf",
+            source_path_before(doc),
+        )
+
+    def testDocumentPageCountMigrated(self):
+        Document = self.apps.get_model("documents", "Document")
+
+        doc = Document.objects.get(id=self.doc_id)
+        self.assertEqual(doc.page_count, 1)
+
+
+class TestMigrateDocumentPageCountBackwards(TestMigrations):
+    migrate_from = "1053_document_page_count"
+    migrate_to = "1052_document_transaction_id"
+
+    def setUpBeforeMigration(self, apps):
+        Document = apps.get_model("documents", "Document")
+        doc = Document.objects.create(
+            title="test1",
+            mime_type="application/pdf",
+            filename="file1.pdf",
+            page_count=8,
+        )
+        self.doc_id = doc.id
+
+    def test_remove_number_of_pages_to_page_count(self):
+        Document = self.apps.get_model("documents", "Document")
+        self.assertFalse(
+            "page_count" in [field.name for field in Document._meta.get_fields()],
+        )