Cerbos Node SDK
Cerbos helps you super-charge your authorization implementation by writing context-aware access control policies for your application resources. Author access rules using an intuitive YAML configuration language, use your Git-ops infrastructure to test and deploy them and, make simple API requests to the Cerbos PDP to evaluate the policies and make dynamic access decisions.
The Cerbos JavaScript client library - sometimes known as an SDK - makes it easy to interact with the Cerbos PDP from your server-side JavaScript applications.
Contents
Requirements
To use the Cerbos JavaScript client library, you'll need:
- Node.js v12 (LTS) or later.
- An instance of the Cerbos PDP needs to be running and accessible by your application. See our Getting Started guide for details.
Note: You can only use the library in server-side JavaScript applications developed in Node.js. It won't work in frontend applications that run in your users' browsers.
Installation
$ npm i @cerbos/sdk
or
$ yarn add @cerbos/sdk
Usage
import { Cerbos } from "@cerbos/sdk";
const cerbos = new Cerbos({
hostname: "http://localhost:9090", // The Cerbos PDP instance
});
const result = await cerbos.check({
actions: ["view", "edit"],
resource: {
policyVersion: "default", // optional
kind: "blogPost", // the name of the resource kind in the policies
instances: {
// Map of instances of resource where the key is the ID
article123: {
// optional user-defined attributes used in policies
attr: {
authorId: "212324",
status: "DRAFT",
},
},
article456: {
// optional user-defined attributes used in policies
attr: {
authorId: "56756",
status: "PUBLISHED",
},
},
},
},
principal: {
id: "userId1", // the ID of the principal accessing the resource
policyVersion: "default", // optional
roles: ["USER"], // from your authentication provider
// optional user-defined attributes used in policies
attr: {
department: "marketing",
},
},
// Optional section for providing auxiliary data.
auxData: {
jwt: {
token: "jwt-token", // JWT to use as an auxiliary data source.
keySetId: "ks1", // ID of the keyset to use to verify the JWT. Optional if only a single keyset is configured.
},
},
});
// Check whether the principal can view article123
const canView = result.isAuthorized("article123", "view"); // boolean
// Check whether the principal can edit article456
const canEdit = result.isAuthorized("article456", "edit"); // boolean
TypeScript
The Cerbos JavaScript client library is written in TypeScript and comes with types.
Configuration
A number of configuration options are avaliable when creating the Cerbos SDK instance:
Hostname (required)
The hostname to the Cerbos PDP instance must be defined when creating the Cerbos instance.
Validation Errors
If you have schema support enabled on your Cerbos PDP then validation errors can be surfaced in the SDK also. To do this set the handleValidationErrors
configuration value to either log
for validation errors to be logged to console or error
for an exception to be thrown should any validation errors occur.
const cerbos = new Cerbos({
hostname: "http://localhost:9090", // The Cerbos PDP instance
handleValidationErrors: 'log', // or 'error'
logLevel: "error",
});
Logging
You can turn on debug logging if you want to check what endpoints are being called and with what arguments.
const cerbos = new Cerbos({
hostname: "http://localhost:9090", // The Cerbos PDP instance
logLevel: "debug",
});
Documentation
You can learn more about the Cerbos in our documentation.