.example.env

@@ -22,6 +22,7 @@ POSTGRES_USER="mw"
 POSTGRES_PASSWORD=
 
 # Backend
+BACKEND_MIN_TEACHER_SELECTION_COUNT=
 BACKEND_URL=URL
 # Backend - API
 BACKEND_API_GRAPHQL_PLAYGROUND=false

docker-compose.yml

@@ -77,6 +77,7 @@ services:
       - redis
     environment:
       BACKEND_URL: ${URL}
+      BACKEND_MIN_TEACHER_SELECTION_COUNT: ${BACKEND_MIN_TEACHER_SELECTION_COUNT}
       BACKEND_API_GRAPHQL_PLAYGROUND: ${BACKEND_API_GRAPHQL_PLAYGROUND}
       BACKEND_API_JWT_SECRET: ${BACKEND_API_JWT_SECRET}
       BACKEND_API_JWT_EXPIRATION: ${BACKEND_API_JWT_EXPIRATION}

docker/backend/src/backend/api/schema/mutation.cr

@@ -143,7 +143,7 @@ module Backend
         def create_vote(context : Context, input : VoteCreateInput) : Vote
           context.student!
 
-          raise "Not enough teachers" if input.teacher_ids.empty?
+          raise "Not enough teachers" if input.teacher_ids.size < Backend.config.min_teacher_selection_count
           teacher_role_count = Db::User.where(role: Db::UserRole::Teacher.to_s).count.run.as(Int64)
           raise "Teachers not registered" if teacher_role_count != Db::Teacher.count ||
                                              teacher_role_count.zero?

docker/backend/src/backend/config.cr

@@ -58,6 +58,9 @@ module Backend
     # Base URL of application
     getter url : String
 
+    # Minimum teacher selection count
+    getter min_teacher_selection_count : Int32
+
     @[EnvConfig::Setting(key: "api")]
     # Configuration for `Api`
     getter api : ApiConfig