The Harness Template Library enables you to standardize and create Templates that you can use across Harness Pipelines and teams.
A Stage Template is a Harness CD, CI, or Approval Stage Template that can be used in any Pipeline in any Project.
This topic walks you through the steps to create a CD Stage Template, but the steps are the same for the other Stage types.
You'll learn how to:
- Create a Deploy Stage Template.
- Define Stage Template parameters.
- Use the Deploy Stage Template in a Pipeline.
Before you begin
- Review Template Library Overview.
- Review Harness Key Concepts to establish a general understanding of Harness.
- The Stage Template in this quickstart is added to a CD Pipeline. If you are new to Harness CD, see CD Quickstarts.
- You can also create CI Build Stage Templates and Manual and Jira Approval Stage Templates. See CIE Quickstarts and Using Manual Harness Approval Stages and Adding Jira Approval Stages and Steps.
- The Stage Template in this quickstart uses Runtime Inputs. Runtime Inputs are placeholders for values that will be provided when you start a Pipeline execution. See Fixed Values, Runtime Inputs, and Expressions.
- You can add Templates to Template Libraries at any scope.
- Tags can be used to group Templates. You can search or filter Templates using these tags.
- You can have nested Templates. You can refer to a stage Template from your Pipeline Template.
Step 1: Create a Template
First, we'll create a Project-level Template in the Deployments module. You can do this in any Project.
Navigate to the Deployments module and in Projects select the desired project.
Next select Templates under Project Setup.
Click New Template.
Select Stage to create a Stage Template.
The Create New Stage Template settings appear.
In Name, enter a name for the stage. You can enter Quickstart.
In Version Label, enter the version of the stage. You can enter v1.
Step 2: Add Stage Parameters
Select Stage Type settings appear.
Select Deploy. The Deploy stage type is a CD Stage that enables you to deploy any Service to your target environment. Other options include Build for CI, and Approval for Manual and Jira Approval Stages. More options will be added soon.
The About Your Stage settings appear, select the type of deployment this Stage must perform. Service is selected by default. A Stage can deploy Services, and other workloads.
Click Set Up Stage. The Template Studio page appears.
In Specify Service, select Runtime input.
Harness Services represent your microservices or applications logically. You can propagate the same Service to as many stages as you need.
Use Runtime Inputs instead of variable expressions: when you want to Template settings in a Stage or step template, use Runtime Inputs instead of variable expressions. When Harness tries to resolve variable expressions to specific Stage-level settings using fully-qualified names, it can cause issues at runtime. Every Pipeline where the Stage or step Template is inserted must use the same names for fully-qualified name references to operate. With Runtime Inputs, you can supply values for a setting at deployment runtime.In Deployment Type, Kubernetes is selected by default. Deployment Type defines how your Service will be deployed.
In Specify Environment, select Runtime input. Environments represent your deployment targets logically (QA, Prod, etc). You can add the same Environment to as many stages are you need.
In Infrastructure Definition, select Kubernetes. Infrastructure Definition represents your target infrastructure physically. They are the actual clusters, hosts, etc. By separating Environments and Infrastructure Definitions, you can use the same Environment in multiple stages while changing the target infrastructure settings with each stage.
Under Cluster Details, select Runtime input in both Connector and Namespace fields. The namespace must already exist during deployment. Harness will not create a new namespace if you enter one here.
Click Next. The Execution Strategies dialog box appears.
Select Rolling and click Use Strategy.
In Execution, you can see the Rollout Deployment step is added automatically.
Your Template is now ready.
Click Save, add a comment, and click Save again.
The Template is published successfully.
You can add variables to your Template as needed.
You can add the following types of values to your variables:
- Fixed values - These cannot be overridden.
- Default values in the Template - These can be overridden.
- Expressions - These can be provided during consumption or at runtime.
- Combination of variables and fixed values - These variables will be automatically created as part of the template.
Step 3: Add the Stage Template to a Pipeline
You can use the CD Stage Template in any Pipeline in your Project now that you have it.
To add a Stage Template to a Pipeline, open the Pipeline, and then click Add Stage.
The Select Stage Type settings appear.
Click Use Template. The next page lists all the Project-level Templates.
Select the Quickstart Template that you created.
Click the Activity Log to track all Template events. It shows you details like who created the Template and Template version changes.
In Details, click Version Label and select Always use the Stable version of the Template.
Selecting this option makes sure that any changes that you make to this version are propagated automatically to the Pipelines using this Template.
Click Use Template.
The About your stage dialog appears. Enter Quickstart and click Set Up Stage.
The Template Stage is added to your Pipeline.
The stage is added and not copied by the Template icon in the stage.
If you had used Copy to Pipeline, this icon would not be there and you could change settings in the stage.
You can now enter all the Runtime Inputs for this Pipeline execution.
You'll notice that you can Change and Remove the Template as needed.
Option: Copy to Pipeline
You can copy the contents of a specific Template to your Pipeline using the Copy to Pipeline option. This does not add any reference to the Template. Copying a Template to a Pipeline is different from linking a Template to your Pipeline. You can't change any stage parameters when you link to a Template from your Pipeline.
To copy a Template, go to your Pipeline. Click Add Stage.
The Select Stage Type settings appear.
Click Use Template. Select the Template you want to copy.
Click Copy to Pipeline.
Enter a name for your stage. Click Set Up Stage.
The Template contents are now copied to your Pipeline stage.
You can change any settings in the stage that you have copied from a Template.