Mercury

Explore Mercury's Authorization Schema in this example, delving into the intricate interplay among users, organizations, and accounts. Uncover the defined user roles, approval workflows, and limits, providing a snapshot of the dynamic relationships within the Mercury ecosystem.

Schema | Open in playground

entity user {}

entity organization {
    relation admin @user
    relation member @user

    attribute admin_approval_limit integer
    attribute member_approval_limit integer
    attribute approval_num integer

    action approve = admin
    action create_account = admin

    permission approval = (member and check_member_approval(approval_num, member_approval_limit)) or (admin and check_admin_approval(approval_num, admin_approval_limit))
}

entity account {
    relation checkings @account
    relation savings @account

    relation owner @organization

    attribute withdraw_limit double
    attribute balance double

    action withdraw = check_balance(balance, request.amount) and (check_limit(withdraw_limit, request.amount) or owner.approval)
}

rule check_balance(balance double, amount double) {
    balance >= amount
}

rule check_limit(withdraw_limit double, amount double) {
    withdraw_limit >= amount
}

rule check_admin_approval(approval_num integer, admin_approval_limit integer) {
    approval_num >= admin_approval_limit
}

rule check_member_approval(approval_num integer, member_approval_limit integer) {
    approval_num >= member_approval_limit
}

Brief Examination of the Model

Mercury's authorization model consists of three primary entities: user, organization, and account. These entities are interconnected through defined relations and governed by specific rules and actions.

Entities & Relations

user: Represents individual users within the system.

organization: Represents organizational entities and establishes relations with users (admin and member). Additionally, this entity holds attributes like admin_approval_limit, member_approval_limit, and approval_num.

account: Represents user accounts with relations to different account types (checkings and savings). It also has a relation to the owning organization and attributes such as withdraw_limit and balance.

Permissions

The authorization schema defines two crucial permissions:

approval: Determines the conditions under which a user (either member or admin) can approve actions based on approval limits.

Need any help ?

This is the end of demonstration of the authorization structure for Facebook groups. To install and implement this see the Set Up Permify section.