chore: add tests for unique index on email and org_id in users table (#10331)

* chore: add tests for unique index on email and org_id in users table

* chore: choose one status code

* chore: choose one status code

* chore: move unique index test into passwordauthn folder

* chore: moved to existing suite, remove register

* chore: better name for file and vars

* chore: fix var name

* chore: fix var name

* chore: fix var name

tests/integration/src/passwordauthn/06_duplicate_invite.py

@@ -0,0 +1,62 @@
+from http import HTTPStatus
+from typing import Callable
+
+import requests
+
+from fixtures.auth import USER_ADMIN_EMAIL, USER_ADMIN_PASSWORD
+from fixtures.types import SigNoz
+
+DUPLICATE_USER_EMAIL = "duplicate@integration.test"
+
+
+def test_duplicate_user_invite_rejected(
+    signoz: SigNoz,
+    get_token: Callable[[str, str], str],
+):
+    """
+    Verify that the unique index on (email, org_id) in the users table prevents
+    creating duplicate users. This invites a new user, accepts the invite, then
+    tries to invite and accept the same email again expecting a failure.
+    """
+    admin_token = get_token(USER_ADMIN_EMAIL, USER_ADMIN_PASSWORD)
+
+    # Step 1: Invite a new user.
+    initial_invite_response = requests.post(
+        signoz.self.host_configs["8080"].get("/api/v1/invite"),
+        json={"email": DUPLICATE_USER_EMAIL, "role": "EDITOR"},
+        headers={"Authorization": f"Bearer {admin_token}"},
+        timeout=2,
+    )
+    assert initial_invite_response.status_code == HTTPStatus.CREATED
+    initial_invite_token = initial_invite_response.json()["data"]["token"]
+
+    # Step 2: Accept the invite to create the user.
+    initial_accept_response = requests.post(
+        signoz.self.host_configs["8080"].get("/api/v1/invite/accept"),
+        json={"token": initial_invite_token, "password": "password123Z$"},
+        timeout=2,
+    )
+    assert initial_accept_response.status_code == HTTPStatus.CREATED
+
+    # Step 3: Invite the same email again.
+    duplicate_invite_response = requests.post(
+        signoz.self.host_configs["8080"].get("/api/v1/invite"),
+        json={"email": DUPLICATE_USER_EMAIL, "role": "VIEWER"},
+        headers={"Authorization": f"Bearer {admin_token}"},
+        timeout=2,
+    )
+
+    # The invite creation itself may be rejected if the app checks for existing users.
+    if duplicate_invite_response.status_code != HTTPStatus.CREATED:
+        assert duplicate_invite_response.status_code == HTTPStatus.CONFLICT
+        return
+
+    duplicate_invite_token = duplicate_invite_response.json()["data"]["token"]
+
+    # Step 4: Accept the duplicate invite — should fail due to unique constraint.
+    duplicate_accept_response = requests.post(
+        signoz.self.host_configs["8080"].get("/api/v1/invite/accept"),
+        json={"token": duplicate_invite_token, "password": "password123Z$"},
+        timeout=2,
+    )
+    assert duplicate_accept_response.status_code == HTTPStatus.CONFLICT