Meta Data Service APIs

Meta Data microservice is the repository of knowledge about the devices and sensors and how to communicate with them that is used by the other services.

Content

• Meta Data's purpose

• Data dictionary

• REST API outline

• Reference

Meta Data’s Purpose

• Is the repository of knowledge about the devices and sensors and how to communicate with them that is used by the other services, such as Core Data, Command, analytics, etc.

• Specifically, Metadata has the following abilities:

  • Manages information about the devices and sensors connected to, and operated by, EdgeX Foundry

  • Knows the type, and organization of data reported by the devices and sensors

  • Knows how to command the devices and sensors

Data Dictionary

• A Device represents a physical device or sensor

  • However, another EdgeX gateway or a system could be a “device”

  • Each device / sensor that is managed by EdgeX Foundry must be registered with Metadata and have a unique ID and name associated to it.

• Device services represent other micro services that manage one or more devices

  • Each device is associated to one and only one device service

  • Each device service has a unique ID and name

• A Device Profile can be thought of as a template of a type or classification of Device.

  • A device profile provides general characteristics for the types of data a device sends and what types of commands or actions can be sent to the device

  • A device must be associated to a single device profile

  • Each profile has a unique ID and name

• Addressable represents some way to address a device or service, and managed by Meta Data

  • Could be an HTTP/REST address/endpoint

  • Could be an MQTT topic

REST API Outline

• Device and Device Service APIs

  • GET's galore to query for Device by id, name, label, associated elements, etc.

• Device Profile APIs

  • GET's galore to query for profile by id, name, label, manufacturer, etc.

• Addressable APIs

  • GET's galore to query for Addressable by id, topic, address url, port, etc.

Some API Examples

GET device by name

http://localhost:48081/api/v1/device/name/{name}

Return Device matching given name (device names should be unique). The information includes the device, device service and device profile.

GET device by addressable name

http://localhost:48081/api/v1/device/addressablename/{addressablename}

Find all devices associated to the Addressable with the specified addressable name.

GET devices by service name

http://localhost:48081/api/v1/device/servicename/{servicename}

Find all devices associated to the Device Service with the specified service name (DeviceService names must be unique).

GET all devices

http://localhost:48081/api/v1/device

Return all devices sorted by id.

GET all device services

http://localhost:48081/api/v1/deviceservice

Return all device services sorted by id.

Reference

Core-metadata API document link: https://docs.edgexfoundry.org/core-metadata.html