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MQTT
MQTT is a lightweight, publish-subscribe, machine to machine network protocol for Message queue/Message queuing service. Joule provides the ability to publish events using MQTT publisher
org.eclipse.paho:org.eclipse.paho.mqttv5.client:1.2.5
mqttPublisher:
clientId: myClientId
username: lyndon
tenant: uk
topic: mydevice/leaf
qos: 1
broker: tcp://127.0.0.1:1883
serializer:
compress: true
security:
jwtclaim:
audienceId: projectID
keyFile: file2
algorithm: RSA
isPrivateKey: true
This basic example leverages the default setting resulting in events published to the
mydevice/leaf topic as StreamEvent Json object. Available configuration parameters
Attribute | Description | Data Type | Required |
|---|---|---|---|
name | Name of source stream | String | |
broker | Broker server address | http://<ip-address>:port | |
topic | Message topic to subscribe too | Strings | |
clientId | A unique client identifier on the server being connected too | String | |
username | Username | String | |
password | password | String | |
tenant | Namespace for created topics | String | |
qos | Quality of service | Integer Default: 0 | |
auto reconnect | Automatically reconnect to broker on disconnection | Boolean Default: true | |
clean restart | This means that if a client disconnects and reconnects within 5 minutes with clean start= false,qos>1 then session state data ( e.g subscribed topics, queued messages) are retained | Boolean Default: true | |
sessionExpiry interval | Maximum time that the broker will maintain the session for once the client disconnects | Long Default: 300 (seconds) 5 minutes | |
registration message | Message to send to broker when a Joule process registers | String | |
user properties | Sets the user properties | Map<String, String> | |
connection timeout | This value, measured in seconds, defines the maximum time interval the client will wait for the network connection to the MQTT server to be established. | Integer Default: 30 (Seconds) | |
keepalive interval | This value, measured in seconds, defines the maximum time interval between messages sent or received. It enables the client to detect if the server is no longer available, without having to wait for the TCP/IP timeout. | Integer Default: 30 (Seconds) | |
serializer | Serialization configuration | See Serialization Attributes section | |
last will | Last will specification | See Last Will Attributes section | |
security | Security configuration |
This topic provides configuration parameters available object serialization process.
Attribute | Description | Data Type | Required |
|---|---|---|---|
transform | User provided implementation | CustomTransformer | |
formatter | This is used when a custom transformer is not provided. Useful when chaining Joule processes | Formatter Default: jsonFormatter | |
compressed | Compress payload using Snappy | Boolean Default: false | |
batch | Flag to batch multiple messages in to a single payload | Boolean Default: false |
The configuration below will serialize StreamEvents as compress Json payloads
serializer:
compress: true
batch: false
These attributes provide the configuration parameters to send publisher disconnection notifications to connected subscribers.
Attribute | Description | Data Type | Required |
|---|---|---|---|
topic | Topic to sent status message on to | String | |
message | Message to send to consumers when publisher no longer exists | String Default: "Publisher disconnected from broker" | |
interval delay | The Server delays publishing the Client's Will Message until the Will Delay Interval has passed or the Session ends, whichever happens first. | Long Default: 5 seconds | |
retain | If message is retained | Boolean Default: true | |
qos | Quality of service | Integer Default: 1 |
last will:
topic: usecasename/status/failure
message: "Joule MQTT process disconnected from broker"
interval delay: 15
Last modified 11mo ago