[WIP][RHCLOUD-37288] add option to list both principal types in one query to the /principals/ endpoint

[petracihalova]

Link(s) to Jira

• RHCLOUD-37288

Description of Intent of Change(s)

the /principals/ endpoint allow to list the user based principals with type=user query param (default option)
you can list service account based principals with type=service-account query param
this PR adds third option type=all to list both principal types in one query:

• first we list service accounts if present
• then we list user based principals
• the filtering with usernames query param is working too (you can combine usernames of both principal types)
• the access token is needed for the query (same as for type=service-account)

example of the response:

{
    "meta": {
        "count": 86,
        "limit": 2,
        "offset": 2
    },
    "links": {
        "first": "/api/rbac/v1/principals/?limit=2&offset=0",
        "next": "/api/rbac/v1/principals/?limit=2&offset=4",
        "previous": "/api/rbac/v1/principals/?limit=2&offset=0",
        "last": "/api/rbac/v1/principals/?limit=2&offset=84"
    },
    "data": {
        "serviceAccounts": [
            {
                "type": "service-account",
                "username": "service-account-de4c127a-f818-4ead-b5b9-1fef9b597513"
                ...
            }
        ],
        "users": [
            {
                "username": "my_user_principal",
                ...
            }
        ]
    }
}

Local Testing

use tenant with few user based principals and service accounts and test queries with(out) the type query param

GET /api/rbac/v1/principals/
GET /api/rbac/v1/principals/?type=user
GET /api/rbac/v1/principals/?type=service-account
GET /api/rbac/v1/principals/?type=all

for example if GET /api/rbac/v1/principals/ returns 10 user based principals and GET /api/rbac/v1/principals/?type=service-account returns 3 service accounts, then GET /api/rbac/v1/principals/?type=all should return 13 principals (both types)

try combinations of limit and offset to check that pagination is working as expected

for example if your tenant contains 3 SA (service accounts) and 4 U (user based principals) then with limit=2 and offset=0 you get this pagination:

page 1 -> 2 SA
page 2 -> 1 SA + 1 U
page 3 -> 2 U
page 4 -> 1 U

Checklist

• open api spec updated
• unit tests
• added the ACs in the ticket