Merge pull request #157 from monzo/unique-external-id

Prevent duplicate external user records for the same app

response/core/models/user_external.py

@@ -12,7 +12,7 @@ def update_or_create_slack(self, *args, **kwargs):
 
 class ExternalUser(models.Model):
     class Meta:
-        unique_together = ("owner", "app_id")
+        unique_together = ("owner", "app_id", "external_id")
 
     owner = models.ForeignKey(User, on_delete=models.PROTECT, null=True, blank=True)
     app_id = models.CharField(max_length=50, blank=False, null=False)

response/migrations/0011_auto_20190927_1339.py

@@ -0,0 +1,18 @@
+# Generated by Django 2.2.3 on 2019-09-27 13:39
+
+from django.conf import settings
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+        ("response", "0010_incident_report_only"),
+    ]
+
+    operations = [
+        migrations.AlterUniqueTogether(
+            name="externaluser", unique_together={("owner", "app_id", "external_id")}
+        )
+    ]