Context Permissions

Action based permissions. Combining request context and flexible requirements.

How it works

1. The request/user provides CONTEXT to cp.require(action, context)
2. ACTION describes the requirments
3. CONTEXT may have roles ROLES and/or PROPERTIES to fulfill the requirements
4. If the CONTEXT satisfies the ACTION cp.require(action, context) returns true

Getting Started

To start using context permissions provide a new instance of ContextPermissions with a actionProfile.
npm i context-permissions
In your project create a new context object

const actionProfile = {
    role1: ['actionA', 'actionB'],
    role2: ['actionC', 'actionD'],
    ...
} 
const cp = new ContextPermissions(actionProfile)
cp.requires(action[, ...action], context)

Testing

This project uses JEST npm test

glossary

• action : descriptive system actions
• scope : specific scoping for actions
• roles : represent a collection of actions
• cp : the Context Permission instance
• requires : the method to sanity check status
• context : represents this session/user properties
• cprm: context permission role memberships, name of the context property that roles are gather from
• actionProfile : describes the ROLE - ACTION relationships

Configuration

• action profile : OPTIONAL but RECOMMENDED. Stored JSON variable required to enable roles.

Step By Step Example

Include the library

const UserPermissions = require('context_permissions')

Defines the roles/actions. Actions SHOULD NOT overlap
note: avoid repeating actions, instead seperate actions into more roles

const actionProfile = {
    treasurer: [
        'manage_money',
        'allocate_expenses',
        'purchases'
    ],
    citizen: [
        'vote'
    ]
    mayor: [
        'city_key'
    ],
    
}

Represents the client state

const context = {
    // these kinds of values can be used to assert ownership or membership to objects
    user: 32, 
    location: 'tokyo',

    // multi-memberships also accepted
    sub_locations: ['north', 'south', 'river'], 
    regions_codes: [362, 346, 123]
    cprm: {

        // these nexted values are assertions about the role known as scope
        board_member: ['farm', 'fishing'], 

        // true provides no assertions
        citizen: true
    }
}

Create a cp object

const { ContextPermissions } = require('context-permissions')
const cp = new ContextPermissions(actionProfile)

simple use case

if (cp.requires('vote', context)){
    // show voting dialog
}

lock by fixed context property

if (cp.requires({location: 'new york'}, context)){
    // content only shown to users with the context.location === 'new york' 
}

lock by action and dynamic context property

// this exerts that the user must have the vote action 
// and that their location must match the objProps.location
const objProps = {
    owner: 32, 
    location: 'tokyo'
}
if (cp.requires({action: 'vote', location: objProps.location}, context)){
    // the current context.location is 'tokyo'
    // so if this objProp is 'tokyo' and the user can vote they see this 
}

lock with many context, only requires 1 of the context claims IF 320 OR 346

if (cp.requires({action: 'mayor', region_codes: [320, 346]}, context)){
    // only mayors with region_codes 320 OR 346
}

See Examples for more

Authors

• Cody Wikman - cwiki.tucson@gmail.com

License

Context Permissions is provided under the MIT LICENSE