Orion Context Broker

The Orion Context Broker is an implementation of the Publish/Subscribe Context Broker GE, providing an NGSI interface. Using this interface, clients can do several operations:

• Query context information. The Orion Context Broker stores context information updated from applications, so queries are resolved based on that information. Context information consists on entities (e.g. a car) and their attributes (e.g. the speed or location of the car).
• Update context information, e.g. send updates of temperature
• Get notified when changes on context information take place (e.g. the temperature has changed)
• Register context provider applications, e.g. the provider for the temperature sensor within a room

This project is part of FIWARE. For more information check the FIWARE Catalogue entry for Core Context Management.

Content

• Background
  • Description
  • Introductory presentations
• Install
• Running
• Usage
• API Walkthrough
• API Reference Documentation
• Testing
  • End-to-end tests
  • Unit Tests
• Advanced topics
• Support
• License

Background

You can find the User & Programmer's Manual and the Installation & Administration Manual on readthedocs.io

Any feedback on this documentation is highly welcome, including bugs, typos or things you think should be included but aren't. You can use github issues to provide feedback.

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Description

Orion is a C++ implementation of the NGSIv2 REST API binding developed as a part of the FIWARE platform.

Orion Context Broker allows you to manage the entire lifecycle of context information including updates, queries, registrations and subscriptions. It is an NGSIv2 server implementation to manage context information and its availability. Context information consists on entities (e.g. a car) and their attributes (e.g. the speed or location of the car).

Using the Orion Context Broker, you are able to create context elements and manage them through updates and queries. In addition, you can subscribe to context information so when some condition occurs (e.g. the context elements have changed) you receive a notification. These usage scenarios and the Orion Context Broker features are described in this documentation.

If this is your first contact with the Orion Context Broker, it is highly recommended to have a look to the brief Quick Start guide.

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Introductory presentations

• Orion Context Broker (en) (jp)
• NGSIv2 Overview for Developers That Already Know NGSIv1 (en) (jp) (no longer maintained since Orion 3.7.0)

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Install

Build and Install documentation for Orion Context Broker can be found at the corresponding section of the Admin Manual.

👉 If you want to run a production-grade instance of orion, carefully read all information in the admin-section.

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Running

How to run Orion Context Broker can be found at this document.

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Usage

In order to create an entity (Room1) with two attributes (temperature and pressure):

curl <orion_host>:1026/v2/entities -s -S --header 'Content-Type: application/json' \
    -X POST -d @- <<EOF
{
  "id": "Room2",
  "type": "Room",
  "temperature": {
    "value": 23,
    "type": "Number"
  },
  "pressure": {
    "value": 720,
    "type": "Number"
  }
}
EOF

In order to query the entity:

    curl <orion_host>:1026/v2/entities/Room2 -s -S --header 'Accept: application/json' | python -mjson.tool

In order to update one of the entity atributes (temperature):

curl <orion_host>:1026/v2/entities/Room2/attrs/temperature -s -S \
    --header 'Content-Type: application/json' \
    -X PUT -d @- <<EOF
{
  "value": 26.3,
  "type": "Number"
}
EOF

or (more compact):

curl <orion_host>:1026/v2/entities/Room2/attrs/temperature/value -s -S \
    --header 'Content-Type: text/plain' \
    -X PUT -d 26.3

Please have a look at the Quick Start guide if you want to test these operations in an actual public instance of Orion Context Broker. In addition, have a look to the API Walkthrough and API Reference sections below in order to know more details about the API (subscriptions, registrations, etc.).

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API Walkthrough

• FIWARE NGSIv2 Orion API Walkthrough FIWARE NGSI v2 (en) (jp) (Markdown)

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API Reference Documentation

API Reference Documentation:

• FIWARE NGSIv2 Orion API (en) (jp) (Markdown)

Orion Reference Documentation:

• Orion Manuals in RTD (en) (jp)

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Testing

End-to-end tests

The functional_test makefile target is used for running end-to-end tests:

make functional_test INSTALL_DIR=~

Please have a look to the section on building the source code in order to get more information about how to prepare the environment to run the functional_test target.

Unit Tests

The unit_test makefile target is used for running the unit tests:

make unit_test

Please have a look to the section on building the source code in order to get more information about how to prepare the environment to run the unit_test target.

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Advanced topics

• Advanced Programming (en) (jp)
• Installation and administration (en) (jp)
• Container-based deployment
  • Docker (en) (jp)
  • Docker Swarm and HA (en) (jp)
• Development Manual (en) (jp)
• Sample code contributions (en) (jp)
• Contribution guidelines (en) (jp), especially important if you plan to contribute with code to Orion Context Broker
• Deprecated features (en) (jp)

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Support

Ask your thorough programming questions using stackoverflow and your general questions on FIWARE Q&A. In both cases please use the tag fiware-orion

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License

Orion Context Broker is licensed under Affero General Public License (GPL) version 3.

© 2023 Telefonica Investigación y Desarrollo, S.A.U

Are there any legal issues with AGPL 3.0? Is it safe for me to use?

There is absolutely no problem in using a product licensed under AGPL 3.0. Issues with GPL (or AGPL) licenses are mostly related with the fact that different people assign different interpretations on the meaning of the term “derivate work” used in these licenses. Due to this, some people believe that there is a risk in just using software under GPL or AGPL licenses (even without modifying it).

For the avoidance of doubt, the owners of this software licensed under an AGPL-3.0 license wish to make a clarifying public statement as follows:

Please note that software derived as a result of modifying the source code of this software in order to fix a bug or incorporate enhancements is considered a derivative work of the product. Software that merely uses or aggregates (i.e. links to) an otherwise unmodified version of existing software is not considered a derivative work, and therefore it does not need to be released as under the same license, or even released as open source.