The mqtt_subscribe node
Subscribe to an mqtt-broker and get data from one or more topics.
Example
|mqtt_subscribe()
.topics('top/grips/#')
.dt_field('UTC-Stamp')
.dt_format('float_micro')
Parameters
| Parameter | Description | Default |
|---|---|---|
host( string ) |
Ip address or hostname of the broker | from config file |
port( integer ) |
The broker's port | 1883 from config file |
user( string ) |
username | from config file |
pass( string ) |
password | from config file |
topics( string_list ) |
mqtt topic(s) to use | undefined |
topic( string ) |
mqtt topic to use | undefined |
qos( integer ) |
Quality of service, one of 0, 1 or 2 | 1 |
dt_field( string ) |
name of the timestamp field that is expected | 'ts' |
dt_format( string ) |
timestamp or datetime format that is expected (see table below) | 'millisecond' |
include_topic ( bool ) |
whether to include the mqtt-topic in the resulting datapoints | true |
topic_as ( string ) |
if include_topic is true, this will be the fieldname for the mqtt-topic value |
'topic' |
as ( string ) |
base object for the output data-point | undefined |
| ssl( is_set ) | whether to use ssl | false (not set) |
One of
topic,topicsmust be specified.
Available datetime formats
| dt_format | description | example |
|---|---|---|
| 'millisecond' | timestamp UTC in milliseconds | 1565343079000 |
| 'second' | timestamp UTC in seconds | 1565343079 |
| 'float_micro' | timestamp UTC float with microsecond precision | 1565343079.173588 |
| 'float_millisecond' | timestamp UTC float with millisecond precision | 1565343079.173 |
| 'ISO8601' | ISO8601 Datetime format string | '2011-10-05T14:48:00.000Z' |
| 'RFC3339' | RFC3339 Datetime format string | '2018-02-01 15:18:02.088Z' |
| 'convtrack_datetime' | special datetime format used in the conveyor tracking data stream | '19.08.01 17:33:44,867 ' |