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Ed-Fi's ODS/API technology allows for the ODS/API to be extended. The ODS/API technology implements extensibility with a defined toolkit that produces regular and predictable patterns. However, the patterns differ by the technology suite.

Please note that your application may not the agency you are partnered with may or may not have extended the API.  Your application will only have to deal with an extended API if they have extended, so the information below may not be relevant to your situation.  

The API extension patterns and other relevant information are covered below.

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Extensibility is a power that is not to be used lightly. Used incorrectly, extensibility is a means of fragmenting the ecosystem in ways that harm the overall goal of interoperability. But handled correctly as a community, customization is an opportunity for further exploration and evolution of the Ed-Fi Data Standard. 

Extensibility in Ed-Fi ODS/API

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Platform

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There are two cases for extensibility: an existing API resource can be extended, or an entirely new API resource can be introduced.

Extensions on an existing entity

In Ed-Fi ODS/API Suite 3Platform, extended elements appear in API resources in an "_ext" object at the root of the JSON for the API resource. Further, extensions are namespaced to provide some indication of their provenance.

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The other extension pattern in the ODS/API is when a new API resource is introduced. In this case, the API resource is also namespaced, but the namespace appears on the path rather than in the JSON.

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