About variables

In orchestrations, variables provide temporary storage locations to hold the input and output data of activities.

This is shown in the example orchestration of the following figure:
Variables flow
During run time, this orchestration extracts data from and stores data into variables as described in the following steps:
  1. The FTP Poll Directory activity polls for a Flat File on an FTP Server and places the contents of the Flat File into the data output parameter. The data output parameter is mapped to the string variable called flatFileRawContent.
  2. The Flat File data returned from the FTP Poll Directory activity is stored as a string into the flatFileRawContent variable.
  3. The flatFileRawContent variable is mapped to the Data input parameter of the Read Flat File activity. The Flat File data is parsed by the Read Flat File activity and returned from the activity in the XML output parameter.
  4. The XML output parameter is mapped to the batchOrderXML Flat File Schema variable. The data is available in the orchestration from the batchOrderXML Flat File Schema variable. For example, if an activity is added to the orchestration to the right of the Read Flat File activity, it can use this data as input.
Variables must be initialized in an orchestration in order for the orchestration to be considered valid. This includes variables that are initialized in the branches of an If.. Then activity. The variable must be initialized in all branches. For more information see Validating the orchestration.

Variable scope

Variables defined within the Group, Try/Catch, If Then, While Loop, or For Each activities are considered as local variables. When such a variable is used as an input of a Map Inputs Tasks activity or a Map Variables activity that is outside of, and following the Group, Try/Catch, If Then, While Loop, or For Each activity, the variable is considered as uninitalized because it is outside the scope of the activities where it was declared. Therefore, these variables must be initialized with a default value.

For more information about specifying a default value, see the Specifying a default value section.

The Variables tab

The Variables tab contains the following panes:
  • Variables: Displays the variables that are defined and available for use in the Mapping Editor. A predefined variable called JobInfo is available in the Variables pane of the Variables tab by default.
  • Schema of <variable>: Displays the schema for the selected variable.
  • Activities using <variable>: Displays all activities in the orchestration which use the variable.
  • Properties of <variable>: Where you define or edit variable properties or specify a default value.

The JobInfo variable

By default, Studio provides the JobInfo variable. The Integration Appliance provides the values for the JobInfo nodes during run time. The JobInfo variable contains the nodes defined in the following table:
JobInfo Node Name Data Type Description
jobId String Contains the job ID number assigned to the instance of the orchestration. When the orchestration starts processing the activities contained in the orchestration, a job ID number is assigned to that instance of the orchestration. This job ID number is also visible from the Web Management Console (WMC).
jobStartTime XML Schema data type xsd:dateTime Contains the date and time that the instance of the orchestration started processing.
Note: The jobStartTime is the date and time that the orchestration starts processing the messages or events and is assigned a job ID number. The jobStartTime is not the date and time that orchestration was deployed on the Integration Appliance and became active —ready to start processing messages and events.  For example, an orchestration contains a FTP Poll Directory activity (a starter activity) that is deployed on the Integration Appliance. The orchestration becomes active waiting for a file to show on the FTP Server in a particular directory. When the orchestration determines that a file has been placed in a particular directory on the FTP Server, it starts processing the FTP Poll Directory activity. When the orchestration starts processing, the current date and time is stored in thejobStartTime node.
projectName String The name of the project that contains the current orchestration.
configurationName String The name of the configuration associated with the current instance of the orchestration. Different configurations of projects are created using the Web Management Console (WMC).
orchestrationName String The name of the orchestration currently processing.
routerHostName String The host name of the Integration Appliance that the current instance of the orchestration is running on.
Note: The JobInfo variable or the nodes of the JobInfo variable cannot be removed.



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Timestamp icon Last updated: Tuesday, 27 September 2016


https://www.ibm.com/support/knowledgecenter/en/SS3LC4_7.5.3/com.ibm.wci.doc/about_variables.html