Using Variables and Functions

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Overview

OpsWise Automation Center supports the following types of variable, all of which can be used in free text fields within tasks:

• User-Defined Variables -- These variables are created by the user.
• Built-In Variables -- These variables are maintained by the system and allow you to access information about task instances and other related data, such as task name, task status, and trigger name.
• Functions -- These calculate some value, such as current date and time, or perform some function, such as ReplaceAll.

Each of these is described in more detail below.

User-Defined Variables

You can define Opswise variables in four different locations:

• Trigger variables are entered by clicking the Variables tab in a trigger. Trigger variables are stored in the table ops_local_variable.
• Task variables are entered by clicking the Variables tab in a task. Task variables are stored in the table ops_local_variable.
• Workflow variables are entered by clicking the Variables tab in a workflow. Workflow variables are stored in the table ops_local_variable.
• Global variables are entered by selecting Automation Center > Variables from the Navigation Pane. Global variables are stored in the table ops_variable.

Once the task has been launched and the variables are resolved, they are referred to as task instance variables. The task instance variables are stored in hashed format in the table ops_map_table.

You can manually launch tasks and temporarily set user-defined variables. Click here for instructions.

Important Note -- Do not define OpsWise Automation Center variables with the prefix “ops_”. That prefix is reserved for built-in variables.

Resolving User-Defined Variables

When OpsWise Automation Center creates a task instance from a task definition, it also resolves all variables specified in its free text fields. Because you can define variables at four different levels (trigger, task, workflow, and global), OpsWise Automation Center follows a prescribed formula to determine which variable takes precedence if duplicate variables have been defined. The general order of precedence is: 1) task trigger, 2) task, 3) workflow trigger, 4) workflow, 5) global.

The following scenarios provide more detailed information about how OpsWise Automation Center variables are resolved.

For tasks launched by a trigger:

1. If the trigger defines the variable in the variables tab, that value is used to resolve the variable.
2. If the trigger does not define the variable, the value from the variable tab in the task definition is used.
3. If neither the trigger nor the task define the variable, the variable definition in the global variables table is used.
4. If the global variables table does not define the variable, the variable remains unresolved.

For tasks launched by a workflow:

1. If the task defines the variable in the variables tab, that value is used to resolve the variable.
2. If the task does not define the variable, and the workflow was launched by a trigger, the value defined in the trigger is used.
3. If the workflow's trigger does not define the variable or the workflow was not launched by a trigger, the value defined in the workflow is used.
4. If the workflow does not define the variable, and there is a parent workflow, the value defined in the parent workflow's trigger is used. If the trigger does not define the variable or if there is no trigger, the value defined in the parent workflow is used. If the parent workflow does not define the variable, the system checks up a level for another parent workflow and repeats the process. This continues until the top level workflow is reached.
5. If the top-level workflow does not define the variable, the variable definition in the global variables table is used.
6. If the global variables table does not define the variable, the variable remains unresolved.

For tasks launched manually:

1. If the task defines the variable in the variables tab, that value is used to resolve the variable.
2. If the task does not define the variable, the variable definition in the global variables table is used.
3. If the global variables table does not define the variable, the variable remains unresolved.

Format for Using Variables

When you enter a variable into a text field, precede the variable with the dollar sign ($) and enclose the variable in curly braces. You can enter a series of variables or nested variables. Examples are:

${variable_name}
${v1}${v2}
${${inner_variable}}

Creating a New Variable

1. For global variables, select Variables from the Navigation Pane. For trigger, task, or workflow variables, click on the Variables tab from the record. OpsWise Automation Center displays a list of variables, if any, as shown in the example below.



2. From the wizard, select New. OpsWise Automation Center displays the Variable screen:



3. Using the field descriptions provided below as a guide, complete the fields as needed.
4. Click the Submit button to save the record and return to the menu, or, right-click and select Save to save the record and remain on the current display.
5. If appropriate, repeat these steps for any additional variables you want to add.

Variable Field Descriptions

The table below describes the fields and buttons on the Variables screen.

Built-In Variables

Built-in variables are maintained by OpsWise Automation Center. They can be used in free text fields and provide information about tasks instances and triggers. They are resolved when the task is launched into a task instance. Some of them are available when a notification is created for an agent, cluster, or connector changes status. Supported built-in variables and their descriptions are provided in the table below. All built-in variables are prefixed with “ops_”.

Triggering with Variables

Overview

OpsWise provides two methods that allow you to manually launch all the tasks associated with a trigger while supplying variable values used by the task(s). These options are available for all trigger types. You will use one of these methods if you want to manually launch the task(s) but cannot use the Launch Task button because you need to override one or more variables.

Two methods are available for triggering tasks while supplying variable values:

• Using the Trigger With Variables popup window. Use this option if you do not want the values you enter for variables to persist. With this option, the values persist only for the time the task(s) is running.
• Using the Variables tab and Trigger Now button. If you want to preserve information about the variables you are setting (the name and value), use the Variables tab.

The variable values you enter when using either option override all others. The variables in the Launch with Variables window override any specified in the Variables tab, but only for this run of the task(s).

The audit message created when you use either method to Trigger with Variables is the same as Trigger Now.

Procedure

Display the Trigger whose tasks you want to launch, and select one of the methods below.

Using the Trigger with Variables Option

1. Click the down-arrow or right-click on the title bar to access the Right-Click menu. A menu displays showing the Trigger With Variables option.



2. Select Trigger With Variables. A pop-up window displays that allows you to enter up to six variables that will be used when executing the task(s) named in the trigger. These can be existing or new variables.



3. When you are finished, click Submit in the pop-up window to launch the tasks named in the trigger. When you click Submit, the variable information in this window is used where referenced in the tasks. After launching the tasks, the system deletes the contents of the window.

Using the Variables Tab

1. Click the Variables tab.
2. Use the New button to add the variables you want to modify.
3. When you are finished, return to the main Trigger page and click Trigger Now to launch the tasks named in the trigger.

Setting Variables in a Workflow

Overview

Within a workflow, you can specify instructions that set a variable to a specific value for use within the workflow. The value you set using this method exists only in memory for the period this workflow is running or until another Set Variable instruction sets it to another value. You can create the Set Variable instruction at the workflow level or task level. If you set it at the workflow level, you have the option of setting it based on the workflow, the tasks (children) in the workflow, or both. If you set it at the task level, you have the option of setting it based on information in the task, in the parent workflow, or both.

The variable need not exist in the database; you can create a new variable using the Set Variable instruction.

When creating a Set Variable instruction, you can trigger the action based on one or more of the following:

• Status
• Exit codes
• Late start
• Late or early finish

Creating a Set Variable Instruction

1. Display the workflow for which you want to create Set Variable instructions.
2. Click on the Actions tab. This tab displays a list of all Actions for this task, including Set Variables, Email Notifications, and Abort Actions.
3. Click New. The Actions wizard displays.



4. Click Set Variable. The Set Variables screen displays.



5. Using the field descriptions provided below as a guide, complete the fields as needed.
6. Click the Submit button to save the record and return to the Actions list, or, right-click and select Save to save the record and remain on the current display.
7. If appropriate, repeat these steps for any additional Set Variable instructions you want to add.

Set Variables Field Descriptions

The table below describes the fields and buttons on the Set Variables screen.

Listing and Setting Variables From the Command Line

You can use the ops-variable-set command to set variables. See Command_Line_Interface_Reference#Table_of_Commands for instructions.

Functions

OpsWise Automation Center supports a number of functions that can be specified in free text fields. They are resolved when the task is launched into a task instance. They are entered using the following formats:

${_function}
${_function(arg1, … , argn)}

The following table lists and describes each supported function.

http://java.sun.com/j2se/1.4.2/docs/api/java/text/SimpleDateFormat.html

http://java.sun.com/j2se/1.4.2/docs/api/java/text/SimpleDateFormat.html