2 files changed, 11 insertions, 6 deletions
diff --git a/gn3/auth/authentication/oauth2/grants/password_grant.py b/gn3/auth/authentication/oauth2/grants/password_grant.py
index 3ec7384..3233877 100644
--- a/gn3/auth/authentication/oauth2/grants/password_grant.py
+++ b/gn3/auth/authentication/oauth2/grants/password_grant.py
@@ -6,6 +6,8 @@ from authlib.oauth2.rfc6749 import grants
 from gn3.auth import db
 from gn3.auth.authentication.users import valid_login, user_by_email
 
+from gn3.auth.authorisation.errors import NotFoundError
+
 class PasswordGrant(grants.ResourceOwnerPasswordCredentialsGrant):
     """Implement the 'Password' grant."""
     TOKEN_ENDPOINT_AUTH_METHODS = ["client_secret_basic", "client_secret_post"]
@@ -13,6 +15,8 @@ class PasswordGrant(grants.ResourceOwnerPasswordCredentialsGrant):
     def authenticate_user(self, username, password):
         "Authenticate the user with their username and password."
         with db.connection(app.config["AUTH_DB"]) as conn:
-            return user_by_email(conn, username).maybe(
-                None,
-                lambda user: valid_login(conn, user, password) and user)
+            try:
+                user = user_by_email(conn, username)
+                return user if valid_login(conn, user, password) else None
+            except NotFoundError as _nfe:
+                return None
diff --git a/gn3/auth/authentication/users.py b/gn3/auth/authentication/users.py
index ce01805..e65938e 100644
--- a/gn3/auth/authentication/users.py
+++ b/gn3/auth/authentication/users.py
@@ -6,6 +6,7 @@ import bcrypt
 from pymonad.maybe import Just, Maybe, Nothing
 
 from gn3.auth import db
+from gn3.auth.authorisation.errors import NotFoundError
 
 class User(NamedTuple):
     """Class representing a user."""
@@ -25,16 +26,16 @@ DUMMY_USER = User(user_id=UUID("a391cf60-e8b7-4294-bd22-ddbbda4b3530"),
                   email="gn3@dummy.user",
                   name="Dummy user to use as placeholder")
 
-def user_by_email(conn: db.DbConnection, email: str) -> Maybe:
+def user_by_email(conn: db.DbConnection, email: str) -> User:
     """Retrieve user from database by their email address"""
     with db.cursor(conn) as cursor:
         cursor.execute("SELECT * FROM users WHERE email=?", (email,))
         row = cursor.fetchone()
 
     if row:
-        return Just(User(UUID(row["user_id"]), row["email"], row["name"]))
+        return User(UUID(row["user_id"]), row["email"], row["name"])
 
-    return Nothing
+    raise NotFoundError(f"Could not find user with email {email}")
 
 def user_by_id(conn: db.DbConnection, user_id: UUID) -> Maybe:
     """Retrieve user from database by their user id"""