Your first scenario in Scenario Studio

In this tutorial you build a small challenge: the learner has to scale a Deployment called web from one replica to three. You place the environment, a setup step that deploys web, a graded task with its check, then try the whole thing in a preview before publishing it. Allow about twenty minutes, a few of which are spent waiting for the preview to provision.

Before you start, you need:

• an organization whose plan includes Scenario Studio (the Instructor plan, or an enterprise contract — see Plans and credits);
• in a subscription organization, an Instructor seat assigned to your account (see Seats). In a contract organization, the instructor, recruiter or admin role is enough (see Members and roles).

Previews are free

Everything you launch from the Studio to test costs nothing: previews debit no credits, and test runs of your checks are never recorded against a learner.

1. Create the draft

1. In the sidebar, open Studio, then Scenario Studio.

2. Click New draft.

3. In Name, type “Scale a Deployment”.

4. In Product type, keep Challenge — graded, hints cost points.

5. In Start from, keep An empty canvas, then click Create draft.

   The empty canvas opens. Everything you do on it is saved automatically: the chip in the toolbar moves from Unsaved changes to Saved.

2. Place the environment

1. In the palette, under Anchor, click Environment. The node appears on the canvas. (You can also drag it where you want it.)

2. Click the Environment node to open its form.

3. In Environment type, pick an environment that contains a Kubernetes cluster, for example Virtual Cluster if your platform offers it. Below the list, chips summarize what the environment can do (number of machines, in-browser editor, pause and resume…).

4. Leave Requests and Limits empty: the environment applies its own values. Click Done.

3. Add the setup step

The setup step prepares what the learner finds on arrival: here, a web Deployment with a single replica.

1. In the palette, under Setup steps, click Manifests.

2. Wire the environment to this step: drag from the output handle of the Environment node to the step’s node. The pipeline always starts at the environment.

3. Click the step’s node. In Name, type deploy-web. The name must be unique within the scenario.

4. Under Manifests, click Add resource, then choose Deployment.

5. Fill in the form:

   • Name: web
   • Namespace: default
   • Image: nginx:1.27
   • Replicas: 1

6. Click Done.

4. Add the task and its check

1. In the palette, under Grading, click Task.

2. Wire the deploy-web step to the task. A task is wired from the step whose result it checks.

3. Click the task’s node and fill in:

   • Task id: scale-web
   • Title: “Scale web to three replicas”
   • Instruction: “The web Deployment in the default namespace runs a single replica. Bring it to three ready replicas.”
   • Points: 10
   • Max attempts: 3

4. Under Validation, click Add check, then fill in:

   • Description: “Three replicas are ready”
   • Type: KubernetesResource — one field of one resource
   • API version: apps/v1
   • Kind: Deployment
   • Name: web
   • Namespace: default
   • JSONPath: .status.readyReplicas
   • CEL expression: exists && value == "3"
   • Points: 10

   Keep Required ticked.

5. Click Done.

Note

With a JSONPath set, the expression reads the field as text in value: compare it to "3", quotes included. The variables available for each check type are listed in Setup steps and checks.

5. Check the canvas

1. In the toolbar, click Check.

2. If “No blocking problems found.” appears, carry on. Otherwise the affected nodes carry a badge: open them, and each node’s Issues tab says what is missing.

6. Try the scenario in a preview

1. In the toolbar, click Preview. The preview drawer opens below the canvas.

2. Click Launch preview. “Provisioning the environment. The terminal appears once it is ready.” shows while the environment is prepared. Meanwhile the deploy-web node moves from Queued to Running, then Applied.

3. When the terminal appears, look at the starting state:

   kubectl get deployment web -n default

4. On the task node, click Test validation. The check fails: there is still only one replica. That is the expected result.

5. Do the learner’s work in the terminal:

   kubectl scale deployment web -n default --replicas=3
   kubectl rollout status deployment web -n default

6. Click Test validation again. The task’s Results tab shows “1/1 checks · 10/10 pts”.

A preview lasts one hour. Extend resets the countdown to one hour, at most three times. When you are done, click Stop in the drawer header.

7. Publish

1. In the toolbar, click Publish.

2. In Scenario name, type scale-a-deployment. The name is lowercase and dash-separated, and it is fixed after the first publish.

3. Click Publish. “Published as scale-a-deployment.” confirms it.

Your challenge now appears in your organization’s catalog with the Studio badge. Members can launch it like any other challenge, and you can add it to a track.

Next steps

• Learn every step type and check type: Setup steps and checks.
• Give the lab a VS Code editor or a tool’s web UI: Editor and app views.
• Edit and republish your scenario: Publish and manage your scenarios.
• Deliver it to a class: Tracks and certification paths.