Working with the Data Workflow Operators
SAP Data Hub Modeler categorizes certain operators as Data Workflow operators, which when executed runs for a limited period of time and finishes with the status either as completed or dead.
The graphs modeled with the data workflow operators are referred to as Data Workflows. The operators in a data workflow communicate with messages transferred at its input and output ports. All data workflow operators have an input, an output, and an error port. Thus, the operator begins execution only when it receives such a message at its input port. The execution of other connected operators in the data workflow begins only after the previous operator has finished its execution.
For example, the following graph includes the data workflow operators, Workflow Trigger, SAP BW Process Chain, SAP HANA Flowgraph, and Workflow Terminator.
In this example, the Workflow Trigger operator sends a start execution message to the SAP BW Process Chain operator. Only after the SAP BW Process Chain operator is executed, the modeler will execute the SAP HANA Flowgraph operator.
Data Workflow Operators
In the SAP Data Hub Modeler, you can access the data workflow operators in the Operators pane under the Data Workflows category. The modeler supports the following data workflow operators.
|
Operator |
Description |
|---|---|
|
SAP BW Process Chain |
Executes an SAP BW process chain in a remote SAP BW system. |
|
SAP HANA Flowgraph |
Executes an SAP HANA flowgraph in a remote SAP HANA system. |
|
Workflow Merge (AND) |
Combines the output from two data workflow operators in a "logical AND". |
|
Workflow Merge (OR) |
Combines the output from two data workflow operators in a "logical OR". |
|
Data Transform |
Provides variety of options for data transformation. |
|
Notification |
Sends email notifications. |
|
Workflow Split |
Duplicates the incoming signal from a data workflow operator. |
|
Workflow Trigger |
Sends a start message to trigger the execution of a data workflow. |
|
Workflow Terminator |
Terminates the current data workflow. |
|
Pipeline |
Executes an SAP Data Hub Modeler graph on either a remote or the local system. |
|
Data Transfer |
Transfers data from an SAP BW system into an SAP Vora table or other major cloud storages. |
|
SAP Data Services Job |
Executes an SAP Data Services Job in a remote SAP Data Services system. |
Modeling Data Workflows
Model data workflows with a Workflow Trigger operator to send the start execution message to the connected operator. You can use the Workflow Terminator operator to shut down the data workflow. This means that, for a given data workflow operator, connect it to the Workflow Trigger or Workflow Terminator operator in case it is the first or last operator that you want to be executed in a data workflow.
Execution Logic and Data Workflow Status
The operators within a data workflow start their execution once it receives such a message at its input port. After executing, each data workflow operator sends a message to the connected operator via its output port if it successfully finished its execution (or via the error port if the execution results in an error).
If the port to which the message is being sent is connected to another operator, the operator that receives the message begins the execution. If the port to which the message is being sent is not connected to another operator, the overall execution of the data workflow stops with the status of the execution as dead.
Importing Certificates for Remote Systems
For operators that leverage HTTPS as the underlying transport protocol (using TLS transport encryption), the certificate of the upstream system needs to be trusted. To import a certificate into the trust chain, obtain the certificates from the target endpoint and import it into the folder, ca in the repository. You can import using the SAP Data Hub Connection Management appication. The next execution of the graph involving the HTTPS connection will automatically pick up any certificate that is present in the folder. For more information on how to create a connection, see Manage Certificates in the Related Information section.