Overview

LF Edge eKuiper is a lightweight IoT data analytics and stream processing engine running on resource-constraint edge devices. The major goal for eKuiper is to provide a streaming software framework in edge side. eKuiper's rule engine allows user to provide either SQL based or graph based rules to create IoT edge analytics applications within few minutes.

The Neuron eKuiper plugin enables users to create north bound nodes publishing collected data to eKuiper for further processing. As an industrial gateway Neuron provides one-stop access to many different devices speaking many different protocols, while eKuiper has the ability of data filtering, aggregation, transformation, and routing. Combining the two products gives you the best of both worlds, which significantly reduces the resource requirements of edge computing solutions and enables more use cases. Better yet, the Neuron eKuiper plugin is open source.

eKuiper integration

The interaction between Neuron and eKuiper is bidirectional and needs support from both sides:

• on the Neuron side, the eKuiper plugin is provided to support publishing data to and receiving commands from eKuiper.
• on the eKuiper side, a Neuron source is provided to support data subscription from Neuron, and a Neuron sink is provided to support device control via Neuron.

Neuron version 2.0.0 first released the eKuiper plugin, while eKuiper 1.5.0 first added the Neuron source and sink. The two sides use the NNG pair0 protocol based on the IPC transport, which only allows one-to-one communication in the same host. Thus you need to deploy Neuron and eKuiper in the same host to achieve correct functionality.

TIP

You may also use MQTT as a relay between Neuron and eKuiper.

NeuronEX

To ease deployment and for better user experience, NeuronEX is released alongside Neuron since version 2.3.0. NeuronEX is a package of Neuron integrated with eKuiper and an augmented dashboard. NeuronEX comes with a default north node data-stream-processing created for you. Using NeuronEX, users can easily manage eKuiper rules directly through the dashboard and perform other stream processing operations.

Internals

This section describes low level communication details between Neuron and eKuiper. You may skip this section without problem.

Data upload

The Neuron eKuiper plugin publishes data collected from devices as JSON once connected to the eKuiper. Data published to eKuiper have the following fields:

• "timestamp": unix timestamp when the data is collected
• "node_name": the name of a southbound node.
• "group_name": the name of a group.
• "values": dictionary storing tags with successfully collected values
• "errors": dictionary storing tags with encountered error codes

Following is an example data. When a tag is read successfully, its value is recorded in the values dictionary. If something goes wrong when reading a tag, the error code is recorded instead in the errors dictionary.

{
  "timestamp": 1646125996000,
  "node_name": "modbus", 
  "group_name": "grp",
  "values": {
    "tag0": 42,
    "tag1": "string"
  },
  "errors": {
    "tag2": 1011
  }
}

Device control

eKuiper may control devices via Neuron by sending write commands using the Neuron sink, and Neuron will write data to the devices upon receiving the commands.

The write command should be JSON data with the following fields:

• "node_name": the name of a southbound node.
• "group_name": the name of a group.
• "tag_name": the name of a tag.
• "value": the value to write.

Below is an example write command:

{
    "node_name": "modbus",
    "group_name": "grp",
    "tag_name": "tag0",
    "value": 1234
}

Examples

See the Data Streaming chapter. Also there is an eKuiper tutorial Stream processing of data collected by Neuron using eKuiper