Principles of operation

AVEVA Events to CONNECT operations focus on event data collection from REST API endpoints.

Agent configuration

For AVEVA Events to CONNECT to start event data collection, configure the following:

• Data source: Provide the REST API Base URL details as data source from which the agent should collect data.

• Resources: Provide the REST API endpoint routes to collect different types of event data.

• Queries: Provide the query strings to form the REST API URL along with the resources path to execute against the data source.

• Schedules: Specify at what time interval data can be polled from the on-premises REST API.

• Data selection: Select the data selection items for the agent to read.

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

When polling for new event data, AVEVA Events to CONNECT combines the Data source (base URL) with the defined resources (API endpoints) and queries and/or data selection. For more information, see Data source and Data selection.

Data connection

The AVEVA Events to CONNECT agent polls the on-premises REST API endpoints for event data and connects securely to it using a Bearer token obtained from either API Key Authentication or Client Credentials authentication security modes.

For more information on secure connections, see Security.

Data collection

The AVEVA Events to CONNECT agent collects event data from REST API endpoints by polling at a scheduled interval. The agent supports Event Types, Events, Reference Data Types, Reference Data, Asset Types, Assets, Authorization Tags, and Enumerations.

Event types

Events are time-oriented operational data. All event data must have a type. You can create and manage a set of namespace-scoped Event Types, which are definitions for domain-specific events and surrounding metadata.

An Event Type is a collection of properties, each configured as:

• A scalar value (int, double, datetime, string, bool, ID, etc.)

• A custom enumeration

• A relationship to another Event Type

• A relationship to a type from an adjacent service (such as assets)

• A collection of any of these things

Event Types have the following base properties:

• id

• eventStartTime

• eventEndTime

• eventDuration

• eventType

• eventState

• createdDate

• modifiedDate

• createdByUser

• authorizationTags

Reference data types

Reference data provides additional information for the context of an event and is useful for users or applications when data is consumed, analyzed, visualized, and reported on. Reference data is typically configuration or system definition information.

Reference Data Types are collections of configurable properties that can include references to other Reference Data or Events.

Reference Data Types have the following base properties:

• id

• createdDate

• modifiedDate

• createdByUser

• authorizationTags

Reference Data Types that reference external data have the following additional base properties:

• sourceId

• resourceId

Type properties

When modeling events and reference data, you give the types a name and add properties to the types. The properties have a name and an Id. The Id cannot be changed, but the name can. Properties can be any of the following scalar types:

• PropertyTypeCode

  • String

  • Boolean

  • Int32

  • Int64

  • Double

  • TimeSpan

  • DateTime

  • Enumeration – defined using the Enumerations endpoint

    • PropertyTypeId is the enumeration Id

It is best practice to name types, properties, and enumerations in a GraphQL-friendly manner. If the name is in the proper format, the generated GraphQLName will be the same as the name. Otherwise, the GraphQLName will not match the name field.

When naming GraphQL types, properties, and enumerations, use the following best practices:

• Name can use these characters: [_A-Za-z][_0-9A-Za-z]

• Types and enum types are Pascal case (MyType)

• Properties are camel case (myProperty)

• Enum values are uppercase

History recovery

AVEVA Events to CONNECT supports History recovery. The agent creates history recovery intervals only on shutdown. Every item is historical by design and there is an automatic history recovery interval on a bad device status.

Data source configuration properties RequestInterval and DataCollectionMode impact history recovery depending on how they are configured. For more information, see Data source and History recovery.