Feature: Audit Trail (#4425)

Adds new feature for optionally enabling change tracking for possible audit purposes
---------

Co-authored-by: shamoon <4887959+shamoon@users.noreply.github.com>
Co-authored-by: Trenton Holmes <797416+stumpylog@users.noreply.github.com>

src/documents/admin.py

@@ -1,3 +1,4 @@
+from django.conf import settings
 from django.contrib import admin
 from guardian.admin import GuardedModelAdmin
 
@@ -12,6 +13,10 @@ from documents.models import ShareLink
 from documents.models import StoragePath
 from documents.models import Tag
 
+if settings.AUDIT_LOG_ENABLED:
+    from auditlog.admin import LogEntryAdmin
+    from auditlog.models import LogEntry
+
 
 class CorrespondentAdmin(GuardedModelAdmin):
     list_display = ("name", "match", "matching_algorithm")
@@ -148,3 +153,12 @@ admin.site.register(StoragePath, StoragePathAdmin)
 admin.site.register(PaperlessTask, TaskAdmin)
 admin.site.register(Note, NotesAdmin)
 admin.site.register(ShareLink, ShareLinksAdmin)
+
+if settings.AUDIT_LOG_ENABLED:
+
+    class LogEntryAUDIT(LogEntryAdmin):
+        def has_delete_permission(self, request, obj=None):
+            return False
+
+    admin.site.unregister(LogEntry)
+    admin.site.register(LogEntry, LogEntryAUDIT)

src/documents/models.py

@@ -20,6 +20,9 @@ from django.utils import timezone
 from django.utils.translation import gettext_lazy as _
 from multiselectfield import MultiSelectField
 
+if settings.AUDIT_LOG_ENABLED:
+    from auditlog.registry import auditlog
+
 from documents.data_models import DocumentSource
 from documents.parsers import get_default_file_extension
 
@@ -872,3 +875,11 @@ class ConsumptionTemplate(models.Model):
 
     def __str__(self):
         return f"{self.name}"
+
+
+if settings.AUDIT_LOG_ENABLED:
+    auditlog.register(Document, m2m_fields={"tags"})
+    auditlog.register(Correspondent)
+    auditlog.register(Tag)
+    auditlog.register(DocumentType)
+    auditlog.register(Note)

src/documents/tasks.py

@@ -37,6 +37,10 @@ from documents.parsers import DocumentParser
 from documents.parsers import get_parser_class_for_mime_type
 from documents.sanity_checker import SanityCheckFailedException
 
+if settings.AUDIT_LOG_ENABLED:
+    import json
+
+    from auditlog.models import LogEntry
 logger = logging.getLogger("paperless.tasks")
 
 
@@ -258,11 +262,37 @@ def update_document_archive_file(document_id):
                     document,
                     archive_filename=True,
                 )
+                oldDocument = Document.objects.get(pk=document.pk)
                 Document.objects.filter(pk=document.pk).update(
                     archive_checksum=checksum,
                     content=parser.get_text(),
                     archive_filename=document.archive_filename,
                 )
+                newDocument = Document.objects.get(pk=document.pk)
+                if settings.AUDIT_LOG_ENABLED:
+                    LogEntry.objects.log_create(
+                        instance=oldDocument,
+                        changes=json.dumps(
+                            {
+                                "content": [oldDocument.content, newDocument.content],
+                                "archive_checksum": [
+                                    oldDocument.archive_checksum,
+                                    newDocument.archive_checksum,
+                                ],
+                                "archive_filename": [
+                                    oldDocument.archive_filename,
+                                    newDocument.archive_filename,
+                                ],
+                            },
+                        ),
+                        additional_data=json.dumps(
+                            {
+                                "reason": "Redo OCR called",
+                            },
+                        ),
+                        action=LogEntry.Action.UPDATE,
+                    )
+
                 with FileLock(settings.MEDIA_LOCK):
                     create_source_path_directory(document.archive_path)
                     shutil.move(parser.get_archive_path(), document.archive_path)

src/documents/views.py

@@ -115,6 +115,9 @@ from paperless import version
 from paperless.db import GnuPG
 from paperless.views import StandardPagination
 
+if settings.AUDIT_LOG_ENABLED:
+    from auditlog.models import LogEntry
+
 logger = logging.getLogger("paperless.api")
 
 
@@ -521,6 +524,18 @@ class DocumentViewSet(
                     user=currentUser,
                 )
                 c.save()
+                # If audit log is enabled make an entry in the log
+                # about this note change
+                if settings.AUDIT_LOG_ENABLED:
+                    LogEntry.objects.log_create(
+                        instance=doc,
+                        changes=json.dumps(
+                            {
+                                "Note Added": ["None", c.id],
+                            },
+                        ),
+                        action=LogEntry.Action.UPDATE,
+                    )
 
                 doc.modified = timezone.now()
                 doc.save()
@@ -546,6 +561,17 @@ class DocumentViewSet(
                 return HttpResponseForbidden("Insufficient permissions to delete")
 
             note = Note.objects.get(id=int(request.GET.get("id")))
+            if settings.AUDIT_LOG_ENABLED:
+                LogEntry.objects.log_create(
+                    instance=doc,
+                    changes=json.dumps(
+                        {
+                            "Note Deleted": [note.id, "None"],
+                        },
+                    ),
+                    action=LogEntry.Action.UPDATE,
+                )
+
             note.delete()
 
             doc.modified = timezone.now()

src/paperless/__init__.py

@@ -1,4 +1,5 @@
 from paperless.celery import app as celery_app
+from paperless.checks import audit_log_check
 from paperless.checks import binaries_check
 from paperless.checks import paths_check
 from paperless.checks import settings_values_check
@@ -8,4 +9,5 @@ __all__ = [
     "binaries_check",
     "paths_check",
     "settings_values_check",
+    "audit_log_check",
 ]

src/paperless/checks.py

@@ -5,9 +5,11 @@ import shutil
 import stat
 
 from django.conf import settings
+from django.core.checks import Critical
 from django.core.checks import Error
 from django.core.checks import Warning
 from django.core.checks import register
+from django.db import connections
 
 exists_message = "{} is set but doesn't exist."
 exists_hint = "Create a directory at {}"
@@ -195,3 +197,19 @@ def settings_values_check(app_configs, **kwargs):
         + _barcode_scanner_validate()
         + _email_certificate_validate()
     )
+
+
+@register()
+def audit_log_check(app_configs, **kwargs):
+    db_conn = connections["default"]
+    all_tables = db_conn.introspection.table_names()
+
+    if ("auditlog_logentry" in all_tables) and not (settings.AUDIT_LOG_ENABLED):
+        return [
+            Critical(
+                (
+                    "auditlog table was found but PAPERLESS_AUDIT_LOG_ENABLED"
+                    " is not active.  This setting cannot be disabled after enabling"
+                ),
+            ),
+        ]

src/paperless/settings.py

@@ -933,6 +933,11 @@ TIKA_GOTENBERG_ENDPOINT = os.getenv(
 if TIKA_ENABLED:
     INSTALLED_APPS.append("paperless_tika.apps.PaperlessTikaConfig")
 
+AUDIT_LOG_ENABLED = __get_boolean("PAPERLESS_AUDIT_LOG_ENABLED", "NO")
+if AUDIT_LOG_ENABLED:
+    INSTALLED_APPS.append("auditlog")
+    MIDDLEWARE.append("auditlog.middleware.AuditlogMiddleware")
+
 
 def _parse_ignore_dates(
     env_ignore: str,

src/paperless/tests/test_checks.py

@@ -1,11 +1,13 @@
 import os
 from pathlib import Path
+from unittest import mock
 
 from django.test import TestCase
 from django.test import override_settings
 
 from documents.tests.utils import DirectoriesMixin
 from documents.tests.utils import FileSystemAssertsMixin
+from paperless.checks import audit_log_check
 from paperless.checks import binaries_check
 from paperless.checks import debug_mode_check
 from paperless.checks import paths_check
@@ -231,3 +233,35 @@ class TestEmailCertSettingsChecks(DirectoriesMixin, FileSystemAssertsMixin, Test
         msg = msgs[0]
 
         self.assertIn("Email cert /tmp/not_actually_here.pem is not a file", msg.msg)
+
+
+class TestAuditLogChecks(TestCase):
+    def test_was_enabled_once(self):
+        """
+        GIVEN:
+            - Audit log is not enabled
+        WHEN:
+            - Database tables contain audit log entry
+        THEN:
+            - system check error reported for disabling audit log
+        """
+        introspect_mock = mock.MagicMock()
+        introspect_mock.introspection.table_names.return_value = ["auditlog_logentry"]
+        with override_settings(AUDIT_LOG_ENABLED=False):
+            with mock.patch.dict(
+                "paperless.checks.connections",
+                {"default": introspect_mock},
+            ):
+                msgs = audit_log_check(None)
+
+                self.assertEqual(len(msgs), 1)
+
+                msg = msgs[0]
+
+                self.assertIn(
+                    (
+                        "auditlog table was found but PAPERLESS_AUDIT_LOG_ENABLED"
+                        " is not active."
+                    ),
+                    msg.msg,
+                )

src/setup.cfg

@@ -21,6 +21,11 @@ omit =
 	paperless/wsgi.py
 	paperless/auth.py
 
+[coverage:report]
+exclude_also =
+    if settings.AUDIT_LOG_ENABLED:
+		if AUDIT_LOG_ENABLED:
+
 [mypy]
 plugins = mypy_django_plugin.main, mypy_drf_plugin.main, numpy.typing.mypy_plugin
 check_untyped_defs = true