Learn about Open Message Format 2​.0

Open Message Format (OMF) 2.0 defines a set of message headers and message bodies that applications can use to send data to a compliant back-end system. OMF supports time-series data, contextual data, asset representations, events, and associated metadata.

This section introduces the OMF 2.0 message model, summarizes the primary changes from earlier OMF message models, and provides guidance for selecting the appropriate message type for new and existing applications.

What's new in OMF 2.0

OMF 2.0 introduces a message model separates structure definitions from runtime values. The schema message type defines types, containers, and relationships before data is sent. The instance message type sends entities, events, streaming data, and relationships that conform to those definitions.

• Schema messages define reusable model information, including types, containers, and type-level relationships.

• Instance messages send data and object instances that conform to an OMF schema, including entities, events, streaming data, and instance-level relationships.

• Typed arrays group related OMF objects within a message body and identify how each group of objects is interpreted.

• Relationship support represents associations between types or between instances to support richer contextual and asset-based models.

• Legacy message support preserves compatibility with existing applications that use type, container, and data messages.

OMF 2.0 and earlier OMF message models

OMF 2.0 uses schema and instance messages as the preferred model for new development. Previous versions of OMF use type, container, and data messages, which remain available for compatibility with existing applications.

When to use OMF 2.0

Use OMF 2.0 for new applications that publish structured data, contextual information, asset representations, events, or time-series values to a compliant back-end system. OMF 2.0 is appropriate when an application must define the data model and then send values or objects that conform to that model.

• Use a schema message to define reusable structure, including types, containers, and relationships.

• Use an instance message to send data or object instances that conform to a schema, including entities, events, streaming values, and relationships between instances.

• Use legacy type, container, and data messages to maintain compatibility with an existing OMF implementation.

Who should use the OMF 2.0 message model

Use the OMF 2.0 message model when developing a new data acquisition or data publishing application, extending an existing application to include richer metadata or relationships, or standardizing message structure across multiple sources and destinations. Existing applications that use type, container, and data messages can continue to use those messages for compatibility. For new development, use schema and instance messages when the destination system supports them.