Prometheus custom metrics in 1.6.0 not working?

Hi Michael,

Switching form env-File to conf was our original intent. however if we set it up that way we can only get the prometheus endpoint to work if we do not activate the mongo-db-pump as well. If we do enable mongo-pump. the prometheus config seems to be entirely ignored. If we disable the mongo-db-pump, the prometheus endpoint works.

{
  "analytics_storage_type": "redis",
  "analytics_storage_config": {
    "type": "redis",
    "host": "<redis-host>",
    "port": 6379,
    "hosts": null,
    "username": "<user>",
    "password": "<pw>",
    "database": 0,
    "optimisation_max_idle": 100,
    "optimisation_max_active": 0,
    "enable_cluster": false
  },
  "purge_delay": 10,
  "pumps": {
    "mongo": {
      "type": "mongo",
      "meta": {
        "collection_name": "tyk_analytics",
        "mongo_url": "mongodb:/<mongo-db-host>:27017/tyk_analytics",
        "collection_cap_max_size_bytes": 1048576,
        "collection_cap_enable": true
      }
    },
    "mongo-pump-aggregate": {
      "type": "mongo-pump-aggregate",
      "meta": {
        "mongo_url": "mongodb:/<mongo-db-host>:27017/tyk_analytics",
        "use_mixed_collection": true
      }
    },
    "prometheus": {
      "type": "prometheus",
      "meta": {
        "listen_address": ":9090",
        "path": "/metrics",
        "custom_metrics": [
          {
            "name": "tyk_http_requests_total",
            "description": "Total of API requests",
            "metric_type": "counter",
            "labels": ["response_code", "api_name", "method", "api_key","alias", "path"]
          },
          {
            "name": "tyk_http_latency",
            "description": "Latency of API requests",
            "metric_type": "histogram",
            "labels": ["type", "response_code", "api_name", "method", "api_key", "alias", "path"]
          }
        ]
      }
    }
  },
  "uptime_pump_config": {
    "collection_name": "tyk_uptime_analytics",
    "mongo_url": "mongodb:/<mongo-db-host>:27017/tyk_analytics",
    "collection_cap_max_size_bytes": 1048576,
    "collection_cap_enable": true
  },
  "dont_purge_uptime_data": false
}