Telegraf无法在MQTT协议中正确读取JSON数据

Question

当我使用telegraf inputs.mqtt_consumer 在订阅MQTT时无法正确解析数据时，

1. 从客户端读取的原始数据：

{
  "air": "air",
  "humidity": 35,
  "region": "shanghai",
  "temperature": 34,
  "time": 1655371268
}

2. 这是Telegraf的配置

[[inputs.mqtt_consumer]]
  servers = ["tcp://127.0.0.1:1883"]
  topics = [
        "test/#"
  ]
  data_format = "json"
  [[inputs.mqtt_consumer.topic_parsing]]
    topic = "air/humidity/region/temperature/time"
    measurement = "measurement/_/_/_/_"
    tags = "_/_/region/_/_"
    fields = "_/_/_/temperature/_"

3. 这是我使用EMQX 就像这样，

> select * from mqtt_consumer
name: mqtt_consumer
time                           humidity temperature topic
----                           -------- ----------- -----
2022-06-16T09:28:45.663600586Z  41       41          test
2022-06-16T09:28:45.764128509Z  38       48          test
2022-06-16T09:28:46.664330569Z  43       47          test
2022-06-16T09:28:46.764848563Z. 41       34          test
2022-06-16T09:28:47.665094746Z. 49       50          test
2022-06-16T09:28:47.765611758Z. 5       50          test
2022-06-16T09:28:48.66629661Z   42       32          test

4. 我希望数据像这样，

name: mqtt_consumer
time                           region   temperature topic
----                           ----     ----------- -----
2022-06-16T09:28:45.663600586Z shanghai 41          test
2022-06-16T09:28:45.764128509Z shanghai 48          test
2022-06-16T09:28:46.664330569Z shanghai 47          test
2022-06-16T09:28:46.764848563Z shanghai 34          test
2022-06-16T09:28:47.665094746Z shanghai 50          test
2022-06-16T09:28:47.765611758Z shanghai 50          test
2022-06-16T09:28:48.66629661Z  shanghai 32          test

5. Telegraf的配置不能更改为

  [[inputs.mqtt_consumer.topic_parsing]]
    topic = "air/humidity/region/temperature/time"
    measurement = "measurement/_/_/_/_"
    tags = "_/_/tag/_/_"
    fields = "_/_/_/field/_"

Answer 1

[[inputs.mqtt_consumer]]
data_format = "json"
tag_keys = [
    "region"
]

请参阅doc