Managing roles

Before start

Make sure you are familiar with:

• Managing permissions

Overview

1. Introduction
2. Defining roles
3. Individual roles
4. Multiple roles
5. Roles with permissions
6. Removing roles
7. Getting all roles
8. Confusion with roles

Introduction

By definition a role is a named set of abilities (permissions) by which a specific group of users is identified. So for example USER or ANONYMOUS would be roles and not permissions. We can represent our USER role as a group of permissions that the role should be able to perform. For example: listArticles, editArticles and other custom server/browser validated privileges.

🔥 Important

Roles are for and operator(&&) between permissions. The whole library is based on permissions. so this line

NgxRolesService
  .addRole('ADMIN', ['read', 'write']);

This means that the user should have read and write permission already loaded to make this line work

<a *ngxPermissionsOnly="['ADMIN']" href="#" data-toggle="modal"></a>

Its possible to do in two ways

1. Create role with already preloaded permissions

NgxRolesService
  .addRoleWithPermissions('ADMIN', ['read', 'write']);

2. add permissions

this.ngxPermissionsService.loadPermissions(['read', 'write'])

and then add role

NgxRolesService
  .addRole('ADMIN', ['read', 'write']);

in this case this lines will work

<a *ngxPermissionsOnly="['ADMIN']" href="#" data-toggle="modal"></a>

<a *ngxPermissionsOnly="['read']" href="#" data-toggle="modal"></a>

💡 Note
It's a good convention to name roles with UPPER_CASE, so roles like ACCOUNTANT or ADMIN are easier to distinguish from permissions.

💡 Note
If You have only names like USER, ADMIN without permissions inside like read, write. Its better to use permissions USER, ADMIN in this case this.ngxPermissionsService.loadPermissions(["USER", "ADMIN"])

---

Individual roles

Similarly to permissions we are gonna use here RolesService that exposes addRole allowing to define custom roles used by users in your application.

[...]

//permissionNameA,B,C should be defined by permissions service
//this.ngxPermissionsService.loadPermissions(["permissionNameA", "permissionNameB", "permissionNameC"])
// If at least one is not available the check will fail.
NgxRolesService
  .addRole('ROLE_NAME', ['permissionNameA', 'permissionNameB', 'permissionNameC', ...])
  
NgxRolesService.addRole('Guest', (roleName, roleObject) => {
      return this.sessionService.checkSession().toPromise();
  }); 

NgxRolesService.addRole('Guest', (roleName, roleObject) => {
      return true;
  }); 

//Alternative You can add permissions with role at the same time
NgxRolesService
  .addRoleWithPermissions('ROLE_NAME', ['permissionNameA', 'permissionNameB', 'permissionNameC', ...])

//or multiple permissions with roles at once
NgxRolesService    
  .addRolesWithPermissions({
    'USER': ['canReadInvoices'],
    'ADMIN': ['canReadInvoices','canEditInvoices','canUploadImages']
  });

Validation function are injected with any angular services. There are 2 local injectables available that can be used to implement more complex validation logic.

Parameter	Description
roleName	String representing name of checked role
transitionProperties	Array or validation function

It also have to return one of values to properly represent results:

Validation result	Returned value
Valid	[true|Promise.resolve() but it should not resolve false]
Invalid	[false|Promise.reject() or Promise.resolve(false)]

Note: Right now to make request to the backend it only supports promises Note: If at least one of request fulfils it will show the component

Usage of addRole is very similar to addPermissions:

NgxRolesService
  // Library will internally validate if 'listEvents' and 'editEvents' permissions are valid when checking if role is valid   
  .addRole('ADMIN', ['listEvents', 'editEvents']);  
  
NgxRolesService.addRole('Guest', () => {
      return this.sessionService.checkSession().toPromise();
  });  
  

Multiple roles

Service NgxRolesService allows you define multiple roles with addRoles method. This method accepts Object containing keys as a role names and corresponding validators as values.

NgxRolesService    
  // Or use your own function/service to validate role
  .addRoles({
    'USER': ['canReadInvoices'],
    'ADMIN': ['canReadInvoices','canEditInvoices','canUploadImages'],
    'GUEST': () => {
        return this.sessionService.checkSessions().toPromise();
    }
  });

Roles with permissions

addRoleWithPermissions function - add roles with permissions preloaded.
addRolesWithPermissions function - add roles with permissions preloaded.

The difference between addRole and addRoleWithPermissions:

addRole doesn't load permissions.
addRoleWithPermissions load permissions.

NgxRolesService
  .addRoleWithPermissions('ROLE_NAME', ['permissionNameA', 'permissionNameB', 'permissionNameC', ...])

NgxRolesService    
  .addRolesWithPermissions({
    'USER': ['canReadInvoices'],
    'ADMIN': ['canReadInvoices','canEditInvoices','canUploadImages']
  });

💡 Note

Removing roles

To remove all roles use flushRoles method:

NgxRolesService.flushRoles();

To remove all roles and permissions flushRolesAndPermissions method:

NgxRolesService.flushRolesAndPermissions();

Alternatively you can use removeRole to delete defined role manually:

NgxRolesService.removeRole('USER');

🔥 Important
This line will not remove permissions of user.

Getting all roles

To get specific role use method getRole:

let role = NgxRolesService.getRole('roleName');

And to get all roles form NgxRolesService use method getRoles or use Observable roles$:

let roles = NgxRolesService.getRoles();

NgxRolesService.roles$.subscribe((data) => {
    console.log(data);
})

Confusion with roles

Given

.addRoles({
'USER': ['canReadInvoices'],
'ADMIN': ['canReadInvoices', 'canEditInvoices', 'canUploadImages'],
'MANAGER': ['canEditInvoices'],
});

based on comment yd021976 Thank to him a lot

Hi, if I can help :

• If you use "roles", then use in your template the role name to check permissions e.g, according to the @cubet-rahul code sample: <a *ngxPermissionsOnly="['ADMIN']" href="#" data-toggle="modal"></a> This will allow "ADMIN" role only, but all permissions of ADMIN role

• If you use "permissions", then use "permission name" in your template e.g, according to the @cubet-rahul code sample: <a *ngxPermissionsOnly="['canEditInvoices']" href="#" data-toggle="modal"></a> this will allow users that have "canEditInvoices", no matter of their roles

In addition, if this doesn't fit your needs, you can provide a validation function when defining role and/or permission. Example: NgxRolesService.addRole('ADMIN",()=>{ check whatever you want and return boolean })

If You have more problems with roles please look into this issues

https://github.com/AlexKhymenko/ngx-permissions/issues/80

https://github.com/AlexKhymenko/ngx-permissions/issues/58

If You have even more please create issue. Or just change the library so it will suit Your needs.

Hope it helps