7.0

Binding Software Properties to Other Properties
In several deployment scenarios, a component needs the property value of another component to
customize itself. In vRealize Automation, this process is called binding to other properties. You can design
your components for property bindings, but you configure the binding when you assemble the blueprint.
In addition to setting a property to a hard-coded value, a software architect, IaaS architect, or application
architect can bind Software component properties to other properties in the application blueprint, such as
an IP address or an installation location. When you bind a Software property to another property, you can
customize a script based on the value of another component property or virtual machine property. For
example, a WAR component might need the installation location of the Apache Tomcat server. In your
scripts, you can configure the WAR component to set the server_home property value to the Apache
Tomcat server install_path property value in your script. As long as the architect who assembles the
application blueprint binds the server_home property to the Apache Tomcat server install_path property,
then the server_home property value is set correctly.
Your component scripts can only use properties that you have defined in those scripts.
Passing Property Values Between Life Cycle Stages
You can modify and pass property values between life cycle stages by using the action scripts.
For a computed property, you can modify the value of a property and pass the value to the next life cycle
stage of the action script. For example, if component A has the progress_status value defined as staged,
in the INSTALL and CONFIGURE life cycle stage you change the value to progress_status=installed in
the respective action scripts. If component B is bound to component A, the property values of
progress_status in the life cycle stages of the action script are the same as component A.
Define in the software component that component B depends on A. This dependency defines the passing
of correct property values between components whether they are in the same node or across different
nodes.
For example, you can update a property value in an action script by using the supported scripts.
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Bash progress_status="completed"
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Windows CMD set progress_status=completed
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Windows PowerShell $progress_status="completed"
Note Array and content property do not support passing modified property values between action scripts
of life cycle stages.
Best Practices for Developing Components
To familiarize yourself with best practices for defining properties and action scripts, you can download and
import Software components and application blueprints from the VMware Solution Exchange.
Configuring vRealize Automation
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