OPA Spring Security Library

OPA Spring Security is a library that enables using OPA for authorization in Spring applications.

Installation

Prerequisites

• Java 11 or higher

Using the starter

Add dependency using Maven

<dependency>
    <groupId>com.bisnode.opa</groupId>
    <artifactId>opa-filter-spring-boot-starter</artifactId>
    <version>{version}</version>
</dependency>

or Gradle

implementation 'com.bisnode.opa:opa-filter-spring-boot-starter:{version}'

Configuration

All properties are prefixed with opa.filter

Property	Default value	Description	Example
enabled	true	Whether the filter should be enabled
documentPath		Name of OPA document path to use for queries	"http/request/authz"
instance	http://localhost:8181	Address of OPA instance
endpointsWhitelist		Comma-separated list of ant patterns to use for matching whitelisted endpoints	/ping,/info,/api-docs/**

Policy requirements

Currently, the filter sends following information to OPA:

• path - path of the resource, that's being requested, e.g. /messages/2
• method - HTTP method, e.g. GET
• encodedJwt - encoded token from authorization (if found, null otherwise)

Those properties are available in your policy's input.

---

Your OPA policy response should contain following properties:

• allow - with value true if to requested resource should be allowed. false otherwise
• reason - an optional string containing reason behind given accessDecision, it will be supplied to exception message

Unknown properties are ignored.

Example OPA response would look as follows:

{
  "result": 
  {
      "allow": false,
      "reason": "You shall not pass"
  }
}

Published events

When library denies access to the resource, AuthorizationFailureEvent is published and therefore can be used in user's code.

Developing and building

Build process and dependency management is done using Gradle. Tests are written in Spock.

Contribution

Interested in contributing? Please, start by reading this document.