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Binary Level System

In this system, user permissions are managed using a binary representation. Each permission is assigned a unique bit within a binary number. By combining different permissions using bitwise operations, we can efficiently store and manage multiple permissions for a user in a single value.

For example, the permissions for a user in the database are stored as:

{
  "ClubStudentsP": 513,
  "ClubAttendancesP": 149,
  "UserGroupP": 130,
  "ClubInformationP": 1
}

Each of these numbers represents a combination of different permissions based on the binary value system. Let's break down how each of these permissions is structured using enumerations in Python.

Permission Structure​

User Group Permissions (UserGroupP)​

The following enum defines the permissions for user management. Each permission is a power of two, allowing multiple permissions to be combined using bitwise OR (|):

class UserGroupP(Enum):
  CHANGE_USERNAME_OWN = 1 << 0  # 1
  CHANGE_PASSWORD_OWN = 1 << 1  # 2
  BLOCK_ACCOUNT = 1 << 2  # 4
  CHANGE_USERNAME_ALL = 1 << 3  # 8
  CHANGE_PASSWORD_ALL = 1 << 4  # 16
  DELETE_ACCOUNT = 1 << 5  # 32
  CREATE_ACCOUNT = 1 << 6  # 64
  VIEW_USER_OWN = 1 << 7  # 128
  VIEW_USER_ALL = 1 << 8  # 256

If a user has 130 as their UserGroupP value in the database, this value is derived from 128 + 2, which means the user has the following permissions:

  • VIEW_USER_OWN
  • CHANGE_PASSWORD_OWN

Club Information Permissions (ClubInformationP)​

For club-related information, we have a similar structure:

class ClubInformationP(Enum):
  REQUEST_INFORMATION_OWN = 1 << 0  # 1
  REVIEW_REQUEST = 1 << 1  # 2
  BEHAVIOUR_POINT_OPERATION = 1 << 2  # 4
  VIEW_INFORMATION_G1 = 1 << 3  # 8
  VIEW_INFORMATION_G2 = 1 << 4  # 16
  VIEW_INFORMATION_AS = 1 << 5  # 32
  VIEW_INFORMATION_A2 = 1 << 6  # 64
  VIEW_INFORMATION_IB = 1 << 7  # 128
  REQUEST_INFORMATION_ALL = 1 << 8  # 256
  VIEW_REQUEST_OWN = 1 << 9  # 512
  VIEW_REQUEST_ALL = 1 << 10  # 1024
  VIEW_INFORMATION_ALL = 1 << 11  # 2048
  CREATE_CLUB = 1 << 12  # 4096

For example, a user with a ClubInformationP value of 1 has the REQUEST_INFORMATION_OWN permission.

Club Attendance Permissions (ClubAttendancesP)​

Club attendance permissions are handled as follows:

class ClubAttendancesP(Enum):
  TAKE_ATTENDANCE_OWN = 1 << 0  # 1
  GRADE_CLUB = 1 << 1  # 2
  REQUEST_LEAVE_OWN = 1 << 2  # 4
  REVIEW_LEAVE = 1 << 3  # 8
  VIEW_LEAVE_OWN = 1 << 4  # 16
  TAKE_ATTENDANCE_ALL = 1 << 5  # 32
  REQUEST_LEAVE_ALL = 1 << 6  # 64
  REVIEW_GRADE_OWN = 1 << 7  # 128
  REVIEW_GRADE_ALL = 1 << 8  # 256
  VIEW_LEAVE_ALL = 1 << 9  # 512

With a value of 149, the user has 128 + 16 + 4 + 1, meaning:

  • REVIEW_GRADE_OWN
  • VIEW_LEAVE_OWN
  • REQUEST_LEAVE_OWN
  • TAKE_ATTENDANCE_OWN

Club Students Permissions (ClubStudentsP)​

Similarly, the student management permissions are structured as:

class ClubStudentsP(Enum):
  EDIT_STUDENT_OWN = 1 << 0  # 1
  EDIT_STUDENT_INFORMATION = 1 << 1  # 2
  EDIT_STUDENT_ALL = 1 << 2  # 4

A value of 513 indicates that the user has 512 + 1 permissions, meaning:

  • EDIT_STUDENT_OWN
  • EDIT_STUDENT_ALL

By using this binary system, permission management becomes more efficient and scalable. Each permission can be combined into a single value, allowing for easy storage and retrieval, while maintaining the flexibility to manage permissions individually through bitwise operations.