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`"describeTopics"`

Return info about MQTT topics

Abstract

The "describeTopics" action returns all available information about specified MQTT topics.

The "describeTopics" action returns all available information about specified MQTT topics.

Request examples

Minimal request example

{
  "api": "mq",
  "apiVersion": "1.0",
  "authToken": "replaceWithAuthtokenFromCreateSession",
  "action": "describeTopics",
  "params": {
    "topics": [
      "test/topic1"
    ]
  }
}

Response examples

Successful response example

{
  "authToken": "authToken",
  "result": {
    "data": [
      {
        "name": "test/topic1",
        "creationTime": "2024-02-01T23:47:45.814",
        "messageCount": 2,
        "lastMessageTime": "2024-02-01T23:47:51.716",
        "averageMessagesPerMinute": 0,
        "averageMessagesPerHour": 0,
        "averageMessagesPerDay": 0,
        "subscriberList": [
          {
            "topicExpression": "#",
            "connectionList": [
              {
                "connection": {
                  "clientId": "mqtt-explorer-001",
                  "ipaddress": "127.0.0.1",
                  "port": 35646,
                  "mqttProtocol": 4,
                  "keepAliveSeconds": 60,
                  "status": "Connected with clean flag = 1",
                  "connectionTime": "2024-01-31T17:31:19"
                },
                "qos": 0
              }
            ]
          },
          {
            "topicExpression": "test/#",
            "connectionList": [
              {
                "connection": {
                  "clientId": "NodeREDSecure",
                  "ipaddress": "127.0.0.1",
                  "port": 36115,
                  "mqttProtocol": 4,
                  "keepAliveSeconds": 60,
                  "status": "Connected with clean flag = 1",
                  "connectionTime": "2024-01-31T17:31:30"
                },
                "qos": 1
              }
            ]
          }
        ],
        "persistence": {
          "topic": "test/topic1",
          "databaseConnectionString": "FAIRCOMS",
          "databaseUserName": "admin",
          "databaseName": "faircom",
          "tableName": "mqtt_msg_test_topic1",
          "ownerName": "admin",
          "threads": 1,
          "tableAutoTimeStamp": true,
          "tableAutoTimeStampIndex": true,
          "tableReplicationReady": true,
          "retentionPolicy": "autoPurge",
          "retentionUnit": "week",
          "retentionPeriod": 4,
          "storeAndForward": true,
          "maxDeliveryRatePerSecond": 0,
          "newSubscriberDeliveryMode": "default",
          "newSubscriberMaxDeliveredMessages": 0,
          "retrySeconds": 20,
          "outputPayloadField": "source_payload"
        }
      }
    ]
  },
  "errorCode": 0,
  "errorMessage": ""
}

`"params"`

The "params" property is an object that contains an action's parameters. Each action defines its own required and optional properties.

Properties summary

Table 1. "params" properties summary

Property	Description	Default	Type	Limits (inclusive)
topics	contains `"topic"` strings	`[]`	array

`"result"`

Properties summary

Table 2. "result" properties summary

Property	Description	Type	Limits (inclusive)
data	specifies an array or object that the server returns, such as records returned by a query Note It is an empty array when there are no results available.	array	Its contents are determined by the action