Audit logs: truncate browser (#9417)

* Audit logs: truncate browser

Closes #9315

* Lint

Author: stsewd

readthedocs/audit/models.py

@@ -66,6 +66,8 @@ class AuditLog(TimeStampedModel):
     and the deleted user/project/organization can be accessed via the ``log_*`` attributes.
     """
 
+    # pylint: disable=too-many-instance-attributes
+
     PAGEVIEW = 'pageview'
     DOWNLOAD = 'download'
     AUTHN = 'authentication'
@@ -196,8 +198,18 @@ def save(self, **kwargs):
         if self.organization:
             self.log_organization_id = self.organization.id
             self.log_organization_slug = self.organization.slug
+
+        self._truncate_browser()
+
         super().save(**kwargs)
 
+    def _truncate_browser(self):
+        browser_max_length = self._meta.get_field("browser").max_length
+        if self.browser and len(self.browser) > browser_max_length:
+            suffix = " - Truncated"
+            truncated_at = browser_max_length - len(suffix)
+            self.browser = self.browser[:truncated_at] + suffix
+
     def auth_backend_display(self):
         """
         Get a string representation for backends that aren't part of the normal login.

readthedocs/audit/tests/test_models.py

@@ -77,3 +77,21 @@ def test_log_attached_to_organization_only(self):
         self.assertEqual(log.organization, self.organization)
         self.assertEqual(log.log_organization_id, self.organization.id)
         self.assertEqual(log.log_organization_slug, self.organization.slug)
+
+    def test_truncate_browser(self):
+        text = "a" * 250
+        log = get(
+            AuditLog,
+            user=self.user,
+            browser=text,
+        )
+        self.assertEqual(log.browser, text)
+
+        text = "a" * 300
+        log = get(
+            AuditLog,
+            user=self.user,
+            browser=text,
+        )
+        self.assertNotEqual(log.browser, text)
+        self.assertTrue(log.browser.endswith(" - Truncated"))