Debug Access Control

There are 5 different ways to debug access control in Aidbox:

• Access policy dev tool

• __debug search parameter

• x-debug header

• su header

• /auth/test-policy endpoint

We recommend using Access Policy Dev Tool.

Access policy dev tool

Access policy dev tool simplifies development and debugging AccessPolicies. It was introduced in March v2303 release of Aidbox.

Access policy dev tool UI

The dev tool is a part of Aidbox UI Console, which aims

• to edit AccessPolicy resource, and

• to give a nice view for AccessPolicy debug output for a specific request in the same place.

The dev tool is split into two sides, the editor side and the result side. On the left side, you define

• AccessPolicy resource and

• HTTP request you are going to debug.

When you press the Save & Run button, the dev tool saves AccessPolicy and performs policy debug operation for the specified request, and displays the result on the right side. You can see there

• Evaluate policy result. List of all access policies and the result of evaluation.

• Parsed HTTP request. It's an internal representation of the request, which Aidbox passes to the eval-policy function.

To use the Access policy dev tool, Aidbox Development mode setting must be enabled.

Sending the request as a user

By default, Aidbox sends requests with your current session (your identity and permissions). To authenticate with another session, add an Authorization header to the request, e.g.

GET /fhir/Patient
Authorization: Bearer eyJ...w5c

__debug query-string parameter

There is a special query-string parameter __debug=policy you can pass to every Aidbox request. It will toggle debug mode for Request Authorization Layer, and in this mode, instead of the actual response client will get an object containing:of the

• full request object;

• an array of existing AccessPolicies;

• evaluation result for every AccessPolicy (under AccessPolicy.evalResult).

To use the header, Aidbox Development mode setting must be enabled.

x-debug: policy request header

For requests with the x-debug: policy header, details of access policy evaluation will be logged.

GET /fhir/Patient
x-debug: policy

# in aidbox logs
# :auth/trace-policy {:access-policy-id :policy-1, :policy-type "sql", ...
# :auth/trace-policy {:access-policy-id :policy-2, :policy-type "json-schema",...

To use the header, Aidbox Development mode setting must be enabled.

su request header

su header allows to switch user on behalf of whom request is executed. Use su=<user/client id> to check how access control works for that user.

To use the header, SU enable setting must be enabled.

su header is only available to admin users, who have at least one AccessPolicy with engine = allow linked to them.

Usual request without the header as an admin:

GET /fhir/Patient

# Response:
Status: 200

Request on behalf of User myid who has no access to the Patient search:

GET /fhir/Patient
su: myid

# Response
Status: 403

/auth/test-policy Operation

You can use a special operation POST /auth/test-policy to design AccessPolicy without creating it.

Post on the /auth/test-policy with:

• a simulated request (you can provide existing user-id and client-id),

• policy code in the policy attribute.

If you want to test JWT auth, put your token in the headers.authorization with the Bearer prefix. In this case, the token will be parsed, and its claims appear in the request.jwt.

JWT in a header is parsed but not validated.

This allows you to test JWT policy without TokenIntrospector registration.

POST /auth/test-policy

request:
  uri: '/fhir/Patient'
  request-method: get
  headers:
    authorization: Bearer <your-jwt>
  user:
    data: {role: 'admin'}
  -- or 
  -- user-id: 'user-1' -- aidbox will find user in database
  client:
    id: basic
    grant_types: ['basic']
  -- or 
  -- client-id: 'client-1' -- aidbox will find client in database
    
policy:
  engine: sql
  sql:
    query: 'SELECT {{user.role}} FROM {{!params.resource/type}}'

The response contains a result of evaluated policy.

request:
  uri: /fhir/Patient
  request-method: get
  user: {role: admin}
  params: {resource/type: Patient}
  #jwt: ...jwt-claims
operation:
  request:
  - get
  - {name: resource/type}
  action: proto.operations/search
  module: proto
  id: Search
policy:
  engine: sql
  sql: {query: 'SELECT {{user.role}} FROM {{!params.resource/type}}'}
result:
  eval-result: false
  query: ['SELECT ? FROM "patient"', admin]

See also

AccessPolicy best practices