IoT Transform Fiware

Description

The iot-transform-fiware service is responsible for transforming incoming sensor data to corresponding fiware entities, if any.

Architecture

Diagrams

C4Component Component_Ext(rabbitmq, "RabbitMQ", "", " ") Component_Ext(broker, "Context Broker", "", " ") Container_Boundary(b1, "iot-transform-fiware") { Container_Boundary(msgp, "Application") { Component(mp, "Message Processor", "", "processes incoming messages") Component(transreg, "Registry", "", "contains all available transformers") Component(transformer, "Transformer", "", "transforms a given payload to a specific entity type") } Container_Boundary(bc, "Context Broker Client") { Component(client, "Client", "", "abstracts the broker's NGSI-LD API") } } Rel(rabbitmq, mp, "delivers messages to", "topic: message.accepted") UpdateRelStyle(rabbitmq, mp, $offsetX="0", $offsetY="-90") Rel(mp, transreg, "finds transformer in") UpdateRelStyle(mp, transreg, $offsetX="-25", $offsetY="-30") Rel(mp, transformer, "forwards message to") UpdateRelStyle(mp, transformer, $offsetX="10", $offsetY="0") Rel(transformer, client, "uses") Rel(client, broker, "creates or updates entities in broker", "https, NGSI-LD") UpdateRelStyle(client, broker, $offsetX="-30", $offsetY="-90") UpdateLayoutConfig($c4ShapeInRow="2", $c4BoundaryInRow="3")

Endpoints

Application

This service does not expose any application endpoints.

Probes

A health endpoint, that can be used by kubernetes probes for instance, is exposed on the default port under /health. A future release will move this endpoint to a separate control and monitoring port.

Links

Where	Address
Git Hub	https://github.com/diwise/iot-transform-fiware

Run

Since the service is distributed as a container image, it can be started using docker or podman. It has a runtime dependency on a running context broker to be able to create or update entities. The url to this broker is specified via an environment variabel. See configuration below.

Refer to the default docker compose configuration in https://github.com/diwise/diwise for details on how to start this service in concert with the rest of the platform.

Configuration

Environment variables

Name	Type	Default	Description
NGSI_CB_URL	url	required	URL to a service exposing the NGSI-LD API. Typically an instance of context-broker.
SERVICE_PORT	integer	8080	The port to accept incoming connections on

Command line flags

This service has no command line flags.

Configuration files

This service has no configuration files.

Operations

Observability and Monitoring

The documented metrics and tracing data below will be generated if the environment variable OTEL_EXPORTER_OTLP_ENDPOINT is set to a valid OTLP collector endpoint such as open telemetry collector.

Logging

All logging is sent to stdout in a structured json format so that it can be filtered and redirected to your logging aggregator of choice. If tracing is enabled the log output will be decorated with the corresponding traceID for easier correlation.

Metrics

This service does not emit any application level metrics, yet.

Tracing

The following traces are created at the application level:

Span	Attributes	Created By	Description
«queue name» receive	none	messaging	Span containing the handling of an incoming message from the message.accepted topic.
create-entity	ngsild-tenant	context broker client	Spans a create entity operation intitiated via the context broker client.
merge-entity	ngsild-tenant entity-id	context broker client	Spans a merge entity operation intitiated via the context broker client.
update-entity-attributes	ngsild-tenant entity-id	context broker client	Spans an update entity attributes operation intitiated via the context broker client.

Run Book

In this section we will list different failure modes for the service, how to detect them based on observability data and how to recover from them.

FAQ

This section is supposed to list questions that get asked frequently by integrators and developers.

License

This document is licensed CC-BY