ensure that username captured from Django is a string (#398)

fixes #397
closes #398

Author: beniwohli

CHANGELOG.md

@@ -5,6 +5,7 @@
 
  * Moved context.url to context.http.url for requests/urllib3 spans (#393, #394)
  * Added support for using route as transaction name in Django 2.2+ (#86, #396)
+ * Fixed an issue with custom user models in Django using non-string usernames (#397, #398)
 
 ## v4.1.0 
 [Check the diff](https://github.com/elastic/apm-agent-python/compare/v4.0.3...v4.1.0)

elasticapm/contrib/django/client.py

@@ -83,12 +83,12 @@ def get_user_info(self, request):
             if hasattr(user, "id"):
                 user_info["id"] = encoding.keyword_field(user.id)
             if hasattr(user, "get_username"):
-                user_info["username"] = encoding.keyword_field(user.get_username())
+                user_info["username"] = encoding.keyword_field(encoding.force_text(user.get_username()))
             elif hasattr(user, "username"):
-                user_info["username"] = encoding.keyword_field(user.username)
+                user_info["username"] = encoding.keyword_field(encoding.force_text(user.username))
 
             if hasattr(user, "email"):
-                user_info["email"] = user.email
+                user_info["email"] = encoding.force_text(user.email)
         except DatabaseError:
             # If the connection is closed or similar, we'll just skip this
             return {}

tests/contrib/django/django_tests.py

@@ -212,6 +212,28 @@ def test_user_info_with_custom_user(django_elasticapm_client, client):
         assert "email" not in user_info
 
 
+@pytest.mark.django_db
+def test_user_info_with_custom_user_non_string_username(django_elasticapm_client, client):
+    with override_settings(AUTH_USER_MODEL="testapp.MyIntUser"):
+        from django.contrib.auth import get_user_model
+
+        MyIntUser = get_user_model()
+        user = MyIntUser(my_username=1)
+        user.set_password("admin")
+        user.save()
+        assert client.login(username=1, password="admin")
+        with pytest.raises(Exception):
+            client.get(reverse("elasticapm-raise-exc"))
+
+        assert len(django_elasticapm_client.events) == 1
+        event = django_elasticapm_client.events[ERROR][0]
+        assert "user" in event["context"]
+        user_info = event["context"]["user"]
+        assert "username" in user_info
+        assert isinstance(user_info["username"], compat.text_type)
+        assert user_info["username"] == "1"
+
+
 @pytest.mark.skipif(django.VERSION > (1, 9), reason="MIDDLEWARE_CLASSES removed in Django 2.0")
 def test_user_info_with_non_django_auth(django_elasticapm_client, client):
     with override_settings(

tests/contrib/django/testapp/models.py

@@ -1,17 +1,26 @@
 # -*- coding: utf-8 -*-
 from __future__ import absolute_import
 
-from django import VERSION as DJANGO_VERSION
+from django.contrib.auth.models import AbstractBaseUser, BaseUserManager
 from django.db import models
 
-if DJANGO_VERSION >= (1, 5):
-    from django.contrib.auth.models import AbstractBaseUser, BaseUserManager
 
-    class MyUser(AbstractBaseUser):
-        USERNAME_FIELD = "my_username"
-        my_username = models.CharField(max_length=30)
+class MyUser(AbstractBaseUser):
+    USERNAME_FIELD = "my_username"
+    my_username = models.CharField(max_length=30)
 
-        objects = BaseUserManager()
+    objects = BaseUserManager()
 
-        class Meta:
-            abstract = False
+    class Meta:
+        abstract = False
+
+
+class MyIntUser(AbstractBaseUser):
+    USERNAME_FIELD = "my_username"
+
+    my_username = models.IntegerField()
+
+    objects = BaseUserManager()
+
+    class Meta:
+        abstract = False