fix(backend): Modellering van ManyToMany-relationships verbeterd

backend/src/entities/assignments/group.entity.ts

@@ -18,6 +18,8 @@ export class Group {
 
     @ManyToMany({
         entity: () => Student,
+        owner: true,
+        inversedBy: "groups"
     })
-    members!: Student[];
+    members: Collection<Student> = new Collection<Student>(this);
 }

backend/src/entities/classes/class.entity.ts

@@ -14,9 +14,9 @@ export class Class {
     @Property({ type: 'string' })
     displayName!: string;
 
-    @ManyToMany(() => Teacher)
+    @ManyToMany({entity: () => Teacher, owner: true, inversedBy: 'classes'})
     teachers!: Collection<Teacher>;
 
-    @ManyToMany(() => Student)
+    @ManyToMany({entity: () => Student, owner: true, inversedBy: 'classes'})
     students!: Collection<Student>;
 }

backend/src/entities/users/student.entity.ts

@@ -8,9 +8,9 @@ import { StudentRepository } from '../../data/users/student-repository.js';
     repository: () => StudentRepository,
 })
 export class Student extends User {
-    @ManyToMany(() => Class)
+    @ManyToMany({entity: () => Class, mappedBy: 'students'})
     classes!: Collection<Class>;
 
-    @ManyToMany(() => Group)
-    groups!: Collection<Group>;
+    @ManyToMany({entity: () => Group, mappedBy: 'members'})
+    groups: Collection<Group> = new Collection<Group>(this);
 }

backend/src/entities/users/teacher.entity.ts

@@ -5,6 +5,6 @@ import { TeacherRepository } from '../../data/users/teacher-repository.js';
 
 @Entity({ repository: () => TeacherRepository })
 export class Teacher extends User {
-    @ManyToMany(() => Class)
+    @ManyToMany({entity: () => Class, mappedBy: 'teachers'})
     classes!: Collection<Class>;
 }