signoz/pkg/query-service/app/integrations/messagingQueues/kafka/consumerLag.md

## Consumer Lag feature break down

### 1) Consumer Group Details

API endpoint:

```
POST /api/v1/messaging-queues/kafka/consumer-lag/consumer-details
```

Request-Body
```json
{
  "start": 1724429217000000000,
  "end": 1724431017000000000,
  "variables": {
    "partition": "0",
    "topic": "topic1",
    "consumer_group": "cg1"
  }
}
```
Response in query range `table` format
```json
{
  "status": "success",
  "data": {
    "resultType": "",
    "result": [
      {
        "table": {
          "columns": [
            {
              "name": "service_name",
              "queryName": "",
              "isValueColumn": false
            },
            {
              "name": "p99",
              "queryName": "",
              "isValueColumn": false
            },
            {
              "name": "error_rate",
              "queryName": "",
              "isValueColumn": false
            },
            {
              "name": "throughput",
              "queryName": "",
              "isValueColumn": false
            },
            {
              "name": "avg_msg_size",
              "queryName": "",
              "isValueColumn": false
            }
          ],
          "rows": [
            {
              "data": {
                "avg_msg_size": "15",
                "error_rate": "0",
                "p99": "0.47993265000000035",
                "service_name": "consumer-svc",
                "throughput": "39.86888888888889"
              }
            }
          ]
        }
      }
    ]
  }
}
```

----

### 2) Producer Details

API endpoint:

```
POST /api/v1/messaging-queues/kafka/consumer-lag/producer-details
```

Request-Body
```json
{
  "start": 1724429217000000000,
  "end": 1724431017000000000,
  "variables": {
    "partition": "0",
    "topic": "topic1"
  }
}
```

Response in query range `table` format
```json
{
  "status": "success",
  "data": {
    "resultType": "",
    "result": [
      {
        "table": {
          "columns": [
            {
              "name": "service_name",
              "queryName": "",
              "isValueColumn": false
            },
            {
              "name": "p99",
              "queryName": "",
              "isValueColumn": false
            },
            {
              "name": "error_percentage",
              "queryName": "",
              "isValueColumn": false
            },
            {
              "name": "throughput",
              "queryName": "",
              "isValueColumn": false
            }
          ],
          "rows": [
            {
              "data": {
                "error_percentage": "0",
                "p99": "5.51359028",
                "throughput": "39.86888888888889",
                "service_name": "producer-svc"
              }
            }
          ]
        }
      }
    ]
  }
}
```

### 3) Network Fetch Latency:

API endpoint:

```
POST /api/v1/messaging-queues/kafka/consumer-lag/network-latency
```

Request-Body
```json
{
  "start": 1724673937000000000,
  "end": 1724675737000000000,
  "variables": {
    "consumer_group": "cg1",
    "partition": "0"
  }
}
```

Response in query range `table` format
```json
{
  "status": "success",
  "data": {
    "resultType": "",
    "result": [
      {
        "table": {
          "columns": [
            {
              "name": "service_name",
              "queryName": "",
              "isValueColumn": false
            },
            {
              "name": "client_id",
              "queryName": "",
              "isValueColumn": false
            },
            {
              "name": "service_instance_id",
              "queryName": "",
              "isValueColumn": false
            },
            {
              "name": "latency",
              "queryName": "latency",
              "isValueColumn": true
            },
            {
              "name": "throughput",
              "queryName": "throughput",
              "isValueColumn": true
            }
          ],
          "rows": [
            {
              "data": {
                "client_id": "consumer-cg1-1",
                "latency": 48.99,
                "service_instance_id": "b0a851d7-1735-4e3f-8f5f-7c63a8a55a24",
                "service_name": "consumer-svc",
                "throughput": 14.97
              }
            },
            {
              "data": {
                "client_id": "consumer-cg1-1",
                "latency": 25.21,
                "service_instance_id": "ccf49550-2e8f-4c7b-be29-b9e0891ef93d",
                "service_name": "consumer-svc",
                "throughput": 24.91
              }
            }
          ]
        }
      }
    ]
  }
}
```

### Onboarding APIs

```
/api/v1/messaging-queues/kafka/consumer-lag/onboarding-producers
```

```
{
    "status": "success",
    "data": {
        "resultType": "",
        "result": [
            {
                "queryName": "onboard_producers",
                "series": [
                    {
                        "labels": {},
                        "labelsArray": [
                            {
                                "result": "All attributes are present and meet the conditions"
                            }
                        ],
                        "values": []
                    }
                ]
            }
        ]
    }
}
```


```
/api/v1/messaging-queues/kafka/consumer-lag/onboarding-consumers
```

```
{
    "status": "success",
    "data": {
        "resultType": "",
        "result": [
            {
                "queryName": "onboard_consumers",
                "series": [
                    {
                        "labels": {},
                        "labelsArray": [
                            {
                                "result": "All attributes are present and meet the conditions"
                            }
                        ],
                        "values": []
                    }
                ]
            }
        ]
    }
}
```

```
127.0.0.1:8080/api/v1/messaging-queues/kafka/consumer-lag/onboarding-kafka
```

```
{
    "status": "success",
    "data": {
        "resultType": "",
        "result": [
            {
                "queryName": "onboard_consumers",
                "series": [
                    {
                        "labels": {},
                        "labelsArray": [
                            {
                                "result": "Neither metric (kafka_consumer_fetch_latency_avg nor kafka_consumer_group_lag) is present in the given time range."
                            }
                        ],
                        "values": []
                    }
                ]
            }
        ]
    }
}
```