List clusters

Example response

[
  {
    "node_groups": [
      {
        "node_updates": {
          "schedule_time": "06:00"
        }
      }
    ],
    "authentication": [
      {
        "issuer_url": "https://accounts.myoidcprovider.com",
        "discovery_url": "https://accounts.myoidcprovider.com/.well-known/openid-configuration",
        "audiences": [
          "client-id-123"
        ],
        "claim_mappings": {
          "username": {
            "claim": "email",
            "prefix": "oidc:",
            "expression": "claims.email"
          },
          "groups": {
            "claim": "email",
            "prefix": "oidc:",
            "expression": "claims.email"
          },
          "uid": {
            "claim": "sub",
            "expression": "claims.sub"
          },
          "extra": [
            {
              "key": "example.org/foo",
              "value_expression": "claims.some_claim"
            }
          ]
        },
        "claim_validation_rules": [
          {
            "claim": "hd",
            "required_value": "upcloud.com",
            "expression": "claims.hd == 'upcloud.com'",
            "message": "User must belong to the upcloud.com organization domain."
          }
        ],
        "user_validation_rules": [
          {
            "expression": "!user.username.startsWith('system:')",
            "message": "Username must not start with the system: prefix."
          }
        ]
      }
    ]
  }
]