For attribute-based (ABAC) or relation-based access control (ReBAC) scenarios: Add support for OPA or OpenFGA

[johakoch]

Couper can act as a PEP (policy enforcement point).

OPA: https://github.com/open-policy-agent/opa
OpenFGA: https://github.com/openfga/go-sdk

Both are decision engines that can be queried either in golang or via HTTP.

OPA is a policy decision agent for which the policies are written in the rego (configuration) language.

OpenFGA is Auth0's open-source implementation of Google's Zanzibar paper; the model schema is described in a DSL, relationships between entities in a model are formulated in tuples (triples, actually).

or AWS's Cedar language: https://www.cedarpolicy.com/en