Vantage6: Set admin user and password from environment or configuration

diff --git a/vantage6-server/vantage6/server/__init__.py b/vantage6-server/vantage6/server/__init__.py
index ea362c1e..c6dcbbd9 100644
--- a/vantage6-server/vantage6/server/__init__.py
+++ b/vantage6-server/vantage6/server/__init__.py
@@ -618,18 +618,30 @@ class ServerApp:
             # TODO use constant instead of 'Root' literal
             root = db.Role.get_by_name("Root")
 
-            log.warn(
-                f"Creating root user: "
-                f"username={SUPER_USER_INFO['username']}, "
-                f"password={SUPER_USER_INFO['password']}"
-            )
+            # Temporary patch
+            # read initial root password from file (docker secret) if provided
+            # TODO: This is a workaround so we don't have an insecure vserver
+            #       at the start. Ideally, we would provide an already hashed
+            #       password. But as hashing is implemented via @validates on
+            #       the field 'password', there isn't a nice way around this.
+            if os.environ.get("V6_INITIAL_ROOT_PASSWORD_FILE"):
+                with open(
+                    os.environ.get("V6_INITIAL_ROOT_PASSWORD_FILE")
+                ) as password_file:
+                    initial_root_password = password_file.read().strip()
+                log.info(
+                    f"Creating root user with password provided via V6_INITIAL_ROOT_PASSWORD_FILE"
+                )
+            else:
+                initial_root_password = SUPER_USER_INFO["password"]
+                log.warn(f"Creating root user with default credentials!")
 
             user = db.User(
                 username=SUPER_USER_INFO["username"],
                 roles=[root],
                 organization=org,
                 email="root@domain.ext",
-                password=SUPER_USER_INFO["password"],
+                password=initial_root_password,
                 failed_login_attempts=0,
                 last_login_attempt=None,
             )