Principles of operation

This adapter's operations focus on data collection and stream creation.

Adapter configuration

For the Adapter for Azure Event Hubs to start data collection, configure the following items:

• Data source: Provide the data source from which the adapter should collect data.

• Data selection: Select Azure Event Hubs items to which the adapter should subscribe for data.

• Logging: Set up the logging attributes to manage the adapter logging behavior.

For more details, see Configure Data source and Configure Data selection.

Azure requirements

In addition to the configuration of a data source, data selection, and logging, you need to configure an Event Hub and an Azure Blob Storage account. Azure Blob Storage is required to store the previously read checkpoint for AVEVA Adapter for Azure Event Hubs in case of disconnection.

For more information on how to create an event hub, see Quickstart: Create an event hub using Azure portal.

For more information on how to create a storage account, see Create a storage account.

Connection

The adapter communicates with the Azure Event Hubs platform using the Advanced Message Queuing Protocol (AMQP) (https://www.amqp.org/about/what). Alternatively, the adapter can connect using AMQP over WebSockets using HTTPS protocol with corresponding adapter configuration.

A Shared Access Signature (SAS) is required for the adapter to authenticate with the Azure Event Hub namespace, which is supplied by a valid connection string in the adapter's data source configuration.

For more information, see Configure Data source.

Data collection

After you configure data source and data selection items, the adapter establishes a connection to each event hub within the event hub namespace for all event hubs specified in data selection items. After a connection is established, the adapter begins consuming events from the event hubs and processes the events as soon as they are published by an event producer and become available to consumers.

For more information see Configure Data selection.

Data types

The following table lists Adapter for Azure Event Hubs supported data type names (case-insensitive) and types of streams created.

Note: Adapter for Azure Event Hubs also supports a limited number of complex data types. For more information, see Configure Data selection.

Stream creation

The Azure Event Hubs adapter creates a stream value with two properties for each selected Azure Event Hubs item. The properties are described in the following table.

Certain metadata are sent with each created stream. The following metadata are common for every adapter type:

• ComponentId: Specifies the data source, for example, EventHubs1

• ComponentType: Specifies the type of adapter, for example, EventHubs

The following metadata are specific to Azure Event Hubs:

• EventHubName: Contains the Azure Event Hub name configured in the data selection item

• DeviceId: Contains the Device Id configured in the data selection item (IoT Hub integration only)

  Note: A configured metadata level allows you to set the amount of metadata for the adapter. Specify the metadata level in Diagnostics and metadata. For the Azure Event Hubs adapter, the following metadata are sent for the individual level:

  None: No metadata

  Low: AdapterType (ComponentType) and DataSource (ComponentId)

  Medium: AdapterType (ComponentType), DataSource (ComponentId), EventHubName, and DeviceId

Each stream created for the selected measurement has a unique identifier (stream ID). If you specify a custom stream ID for the measurement in the data selection configuration, the adapter uses that stream ID to create the stream. Otherwise, the adapter constructs the stream ID using the following format:

<Id>.<ValueField>

Note: Naming convention is affected by StreamIdPrefix and DefaultStreamIdPattern settings in the data source configuration. For more information, see Configure Data source.