Promise based HRBAC (Hierarchical Role Based Access Control) implementation for Node.js
v3 is a rewrite of the library as such there are important changes:
npm install easy-rbac
npm test
Require and create rbac
object.
const RBAC = require('easy-rbac');
const rbac = new RBAC(opts);
Or use create function
const rbac = require('easy-rbac').create(opts);
Options for RBAC can be either an object, function returning a promise or a promise
The expected configuration object example:
{
user: { // Role name
can: [ // list of allowed operations
'account',
'post:add',
{
name: 'post:save',
when: async (params) => params.userId === params.ownerId
},
'user:create',
{
name: 'user:*',
when: async (params) => params.id === params.userId
}
]
},
manager: {
can: ['post:save', 'post:delete', 'account:*'],
inherits: ['user']
},
admin: {
can: ['rule the server'],
inherits: ['manager']
}
}
The roles
property is required and must be an object. The keys of this object are counted to be the names of roles.
Each role must have a can
property, which is an array. Elements in the array can be strings or objects.
If the element is a string then it is expected to be the name of the permitted operation.
If the element is an object:
name
and when
properties
name
property must be a stringwhen
property must be a function that returns a promiseEach name of operation can include *
character as a wildcard match. It will match anything in its stead. So something like account:*
will match everything starting with account:
.
Specific operations are always prioritized over wildcard operations. This means that if you have a definition like:
{
user: {
can: [
'user:create',
{
name: 'user:*',
when: async (params) => params.id === params.userId
}
]
}
}
Then user:create
will not run the provided when operation, whereas everything else starting with user:
does
After initialization you can use the can
function of the object to check if role should have access to an operation.
The function will return a Promise that will resolve if the role can access the operation or reject if something goes wrong or the user is not allowed to access.
rbac.can('user', 'post:add')
.then(result => {
if (result) {
// we are allowed access
} else {
// we are not allowed access
}
})
.catch(err => {
// something else went wrong - refer to err object
});
The function accepts parameters as the third parameter, it will be used if there is a when
type operation in the validation
hierarchy.
rbac.can('user', 'post:save', {userId: 1, ownerId: 2})
.then(result => {
if (result) {
// we are allowed access
} else {
// we are not allowed access
}
})
.catch(err => {
// something else went wrong - refer to err object
});
You can also validate multiple roles at the same time, by providing an array of roles.
rbac.can(['user', 'manager'], 'post:save', {userId: 1, ownerId: 2})
.then(result => {
if (result) {
// we are allowed access
} else {
// we are not allowed access
}
})
.catch(err => {
// something else went wrong - refer to err object
});
If the options of the initialization is async then it will wait for the initialization to resolve before resolving any checks.
const rbac = require('easy-rbac')
.create(async () => opts);
rbac.can('user', 'post:add')
.then(result => {
if (result) {
// we are allowed access
} else {
// we are not allowed access
}
})
.catch(err => {
// something else went wrong - refer to err object
});
The MIT License (MIT) Copyright (c) 2015 Karl Düüna
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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