express-mongoose-cerbos

An example application of integrating Cerbos with an Express server using Mongoose as the ORM. 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.

Dependencies

• Node.js
• MongoDB 7.0
• Docker for running the Cerbos Policy Decision Point (PDP)

Getting Started

1. Install node dependencies

npm install

2. Start up the Cerbos PDP instance docker container. This will be called by the express app to check authorization.

./cerbos/start.sh

3. Start up Mongo

npm run mongo

4. Start the express server

npm run dev

Seed Users

The seed command will create the following users in the database. Authentication is done via Basic authentication using the following credentials. The Role and Department is loaded from the database after successful authentication.

ID	Username	Password	Role	Department
1	alice	supersecret	Admin	IT
2	john	password1234	User	Sales
3	sarah	asdfghjkl	User	Sales
4	geri	pwd123	User	Marketing

Policies

This example has a simple CRUD policy in place for a resource kind of contact - like a CRM system would have. The policy file can be found in the cerbos/policies folder here.

Should you wish to experiment with this policy, you can try it in the Cerbos Playground.

The policy expects one of two roles to be set on the principal - admin and user and an attribute which defines their department as either IT, Sales or Marketing.

These roles are authorized as follows:

Action	Role: User	Role: Admin
read	If they own the contact, the contact is active and the department is Sales, or the contact is active, they are in Marketing and marketingOptIn is true.	Y
create	Only if department is Sales	Y
update	Only if they own the contact being accessed	Y
delete	Only if they own the contact being accessed	Y

Example Requests

Get all contact

As a Admin user => 200 OK with all contacts

curl -i http://alice:supersecret@localhost:3000/contacts

As a Sales user => 200 OK with filtered results

curl -i http://john:password1234@localhost:3000/contacts

As a Marketing user => 200 OK with filtered results

curl -i http://geri:pwd123@localhost:3000/contacts