Merge remote-tracking branch 'origin/dev' into feat/endpoints-beschermen-met-authenticatie-#105

# Conflicts:
#	backend/src/controllers/assignments.ts
#	backend/src/controllers/questions.ts
#	backend/src/data/questions/question-repository.ts
#	backend/src/interfaces/question.ts
#	backend/src/routes/assignments.ts
#	backend/src/routes/classes.ts
#	backend/src/routes/groups.ts
#	backend/src/routes/teachers.ts
#	backend/src/services/questions.ts
#	common/src/interfaces/question.ts

common/src/interfaces/assignment.ts

@@ -2,7 +2,7 @@ import { GroupDTO } from './group';
 
 export interface AssignmentDTO {
     id: number;
-    class: string; // Id of class 'within'
+    within: string;
     title: string;
     description: string;
     learningPath: string;

common/src/interfaces/class-join-request.ts

@@ -1,8 +1,8 @@
 import { StudentDTO } from './student';
-import { ClassJoinRequestStatus } from '../util/class-join-request';
+import { ClassStatus } from '../util/class-join-request';
 
 export interface ClassJoinRequestDTO {
     requester: StudentDTO;
     class: string;
-    status: ClassJoinRequestStatus;
+    status: ClassStatus;
 }

common/src/interfaces/class.ts

@@ -3,5 +3,4 @@ export interface ClassDTO {
     displayName: string;
     teachers: string[];
     students: string[];
-    joinRequests: string[];
 }

common/src/interfaces/group.ts

@@ -1,7 +1,9 @@
 import { AssignmentDTO } from './assignment';
+import { ClassDTO } from './class';
 import { StudentDTO } from './student';
 
 export interface GroupDTO {
+    class: string | ClassDTO;
     assignment: number | AssignmentDTO;
     groupNumber: number;
     members?: string[] | StudentDTO[];

common/src/interfaces/teacher-invitation.ts

@@ -1,8 +1,16 @@
 import { UserDTO } from './user';
-import { ClassDTO } from './class';
+import { ClassStatus } from '../util/class-join-request';
 
 export interface TeacherInvitationDTO {
     sender: string | UserDTO;
     receiver: string | UserDTO;
-    class: string | ClassDTO;
+    classId: string;
+    status: ClassStatus;
+}
+
+export interface TeacherInvitationData {
+    sender: string;
+    receiver: string;
+    class: string;
+    accepted?: boolean; // Use for put requests, else skip
 }

common/src/util/class-join-request.ts

@@ -1,4 +1,4 @@
-export enum ClassJoinRequestStatus {
+export enum ClassStatus {
     Open = 'open',
     Accepted = 'accepted',
     Declined = 'declined',