Variables store dynamic values which can be used during the build process. A full description and further conceptual information can be found on the Variables, Objects & Expressions concept page.
This page discusses information regarding the hands-on use of variables.
Additional Variable Information
Each variable must be assigned a type which limits what time of information can be stored in a variable. Note that all variable types, except expression variables, can have their values changed during the build process.
A full list of variable types can be found on the Variable Types page.
Variable Prompt Types
All configuration variables can be assigned a prompt type which enables users to set a variable's value when queuing a manual build.
Configuration Variables can be given the following prompt types:
- Date Time
- Time Span
- Multiple Selection
Read the Variable Prompt Types page for more information on these prompt types.
Variable namespaces control where a variable exists within the Continua CI environment. Namespaces also provide variables with a scope which limits what each build can access. For example, if you create a configuration variable then only builds from that configuration can access that variable.
Continua uses a namespace hierarchy (as shown below) to determine which variable value should be returned when no namespace has been defined. Read the Variable Namespace Hierarchy section on the Variables, Objects & Expressions concept page for a closer look at how the Continua hierarchy works.
Build variables belong to a specific build however they cannot be created manually. They are used to override any of the variables listed below. See the next section for more information on how build variables work. Build variables can be accessed with the %MyVariableName% syntax (Note that you cannot use the Build namespace prefix).
When a build is created, it automatically creates build variables for every configuration variable that has been defined. It automatically sets the build variable's value to the same value as the configuration variable unless the value is overridden automatically with Triggers or manually through the queue dialog.
Configuration variables are created on a specific configuration and they can only be accessed by builds that belong to that configuration. Configuration variables are read-only at run time and they can be accessed with the %Configuration.MyVariableName% syntax.
Configuration Variables can be created, modified and deleted through the Configuration Wizard.
Project variables are created on a specific project and they can only be accessed by configurations and builds that belong to that project. Project variables are read-only at run time and they can be accessed with the %Project.MyVariableName% syntax.
Project Variables can be created, modified and deleted through the Project Wizard.
Application variables are system wide variables that every build, configuration and project can access. This means that any variable defined in the application namespace can be used anywhere in Continua CI. These are the highest variables that the user can define. Application variables are read-only at run time and they can be accessed with the %Application.MyVariableName% syntax.
Application Variables can be created, modified and deleted through the Variables page in the administration section.
Environment variables are created from the server's environment variables automatically and cannot be changed. These variables can be accessed system wide by every build. Environment variables are always read-only and they can be accessed with the %Environment.MyVariableName% syntax.
Creating and Editing Variables
Configuration, Project and Application variables are all created in the same way through their respective pages. So configuration variables are created through the Configuration Wizard, project variables are created through the Project Wizard and application variables are created through the variables page in the administration section.
All variables, regardless of their namespace, are created in the same way. The only exception are Configuration variables which can also be assigned a prompt type.
When defining a variable, you can specify the following properties:
The name is what you will reference whenever you call this variable. In the screenshot above, I would reference this variable with the following syntax: %myVariable%
This description is shown on all variables pages and it is also displayed on the Queue Build dialog as help text.
Variables can be set to several different types that affect which values can be stored in the variable. The Variable Types page has a full list of types and their definitions.
This is the actual value that the variable will store. Note that all variables (except Build variables) will never change their value during the build process. Instead, if you change a variables value, it will create a build variable with the same name and the new value.
Prompt Type - Configuration Variables Only
Prompt types determine what values the user can specify when a build is queued manually. The Variable Prompt Types page has a full list of prompt type and their definitions.