OData Reader

The Open Data Protocol (OData) is a web protocol for querying and updating data that builds upon web technologies such as HTTP, Atom Publishing Protocol (AtomPub) and JSON to provide access to remote information.

The OData specification defines the request and response rules for the retrieval of both spatial and non-spatial geographic information using either ATOM or JSON; however, the reader currently only uses and understands ATOM format.

This chapter assumes familiarity with the OData, ATOM, HTTP, XML, feeds, entries, properties, URIs, and cloud computing in general.

OData is released under the Open Specification Promise to allow anyone to freely interoperate with OData implementations.

OData Product and System Requirements

Format

Product

Operating System

Reader/Writer

FME Desktop License

FME Server

FME Cloud

Windows

Linux

Mac

Reader

Available in FME Professional Edition and higher

Yes

Yes

64-bit: Yes

Yes

Yes

Reader Overview

The OData reader currently supports version 2.0 through 4.0 of the protocol specification, which can be found at the OData website. Notably, the OData reader now has support for spatial data, including geometry and geography types. The difference between these two types will be explained in this document.

OData services are composed of feeds (also referred to as entity sets), which are collections of typed entries. Each entry represents a structured record with a key that has a list of properties of primitive or complex types.

The OData Reader produces an FME feature for each entry in a feed for the provided service. Each property on an entry becomes an attribute on the FME Feature.

Reader Terminology

The following table maps each OData term to its FME counterpart.

OData FME
Service Dataset
Entity Set (Feed) Feature Type
Entry Feature
Property Attribute name
Complex Type Attribute containing sub-attributes