Lab 2.2 — Build and Deploy with OpenCode

You have a Dev Space, an LLM, and a template repository that encodes your platform’s rules in AGENTS.md. You will use two focused OpenCode sessions to go from zero to a running application on OpenShift.

Estimated time: 30 minutes
Persona: Developer
What you build: A Fortune Cookie web application in Go — generated, built with Tekton, and deployed via your own Argo CD instance

OpenCode reads AGENTS.md before every prompt. You do not need to repeat platform rules — just describe what you want. The LLM knows the standards it must follow, including the exact Dockerfile template and how to call the deploy scripts.

Step 1: Open the Project and Launch OpenCode

Dev Spaces already cloned the template when you created your workspace — it is in ${PROJECT_SOURCE}. Open a terminal and navigate to it:

cd ${PROJECT_SOURCE}

# Confirm the template files are present
ls

Expected

AGENTS.md  deploy/  devfile.yaml  gitops/  opencode.json  pipeline/  scripts/

Launch OpenCode:

opencode

The template provides three Ansible playbooks that OpenCode will call, plus the Kustomize manifests they apply:

Playbook What it does Duration

Playbook	What it does	Duration
`scripts/git-push.yml`	Creates your personal repo on the Git server and pushes all code	~30s
`scripts/build-image.yml`	Applies `pipeline/base` (Kustomize), runs Tekton PipelineRun	3–5 min
`scripts/gitops-deploy.yml`	Applies `gitops/base` (Kustomize ArgoCD), creates Application	2–3 min

scripts/git-push.yml

Creates your personal repo on the Git server and pushes all code

~30s

scripts/build-image.yml

Applies pipeline/base (Kustomize), runs Tekton PipelineRun

3–5 min

scripts/gitops-deploy.yml

Applies gitops/base (Kustomize ArgoCD), creates Application

2–3 min

These playbooks are also exposed as one-click tasks in the DevSpaces sidebar (rocket icon). OpenCode calls them the same way — each task prints named steps so you can follow what is happening.

Session 1: Plan

The plan agent is read-only. It analyses the request and produces a detailed implementation plan without writing any files. Use it first to surface design decisions and let OpenCode internalize AGENTS.md.

Type this prompt in OpenCode:

/plan

I want a Fortune Cookie web application in Go.

The app serves:
- GET /   — an HTML page that displays a random fortune cookie message
            (hard-code at least 10 messages in a slice)
- GET /healthz — returns {"status":"ok"} for Kubernetes health probes

Read AGENTS.md and produce a complete implementation plan:
- File list and purpose of each file
- HTTP handler logic
- Dockerfile stages (follow the template in AGENTS.md exactly)
- Deploy steps using the three scripts

Do not write any code yet. Only plan.

Review the plan. Adjust if needed. When satisfied, proceed to Session 2.

Session 2: Build and Deploy

This single session does everything: generates code, verifies the local build, then calls the deploy scripts in order. Start a new session (Ctrl+N):

/build

Implement the Fortune Cookie application following AGENTS.md strictly.

== Phase 1: Generate code

Generate these files:
1. main.go       — HTTP server on :8080, / (HTML fortune) and /healthz handlers
2. go.mod        — module: fortune-cookie, go 1.22
3. Dockerfile    — use the exact two-stage template from AGENTS.md
                   (ubi9/go-toolset builder → ubi9/ubi-minimal runtime, USER 1001)

After writing every file, run:
  CGO_ENABLED=0 go build -buildvcs=false -o /dev/null .

Fix any compile error before continuing. Show the build output.

== Phase 2: Deploy

Once the build succeeds, run the three Ansible playbooks from AGENTS.md in order:

  ansible-playbook scripts/git-push.yml
  ansible-playbook scripts/build-image.yml
  ansible-playbook scripts/gitops-deploy.yml

Read each playbook's task output. Wait for it to succeed before running the next.
If a task fails, the error is shown inline — read it and fix the root cause.

At the end, print:
- The app route URL
- The personal Argo CD console URL

OpenCode will work through both phases automatically, reporting each step. You will see the Dockerfile it generates, the binary being compiled, and the three Ansible playbooks executing — each one printing named tasks so you can follow exactly what the platform is doing.

Checkpoint

Verify your application is live:

APP_ROUTE=$(oc get route $APP_NAME -n ${APP_NAME}-dev \
  -o jsonpath='{.spec.host}' 2>/dev/null)
ARGOCD_ROUTE=$(oc get route argocd-server -n ${APP_NAME}-dev \
  -o jsonpath='{.spec.host}' 2>/dev/null)

echo "================================================"
echo " App:    https://${APP_ROUTE}"
echo " ArgoCD: https://${ARGOCD_ROUTE}"
echo "================================================"

curl -sk https://${APP_ROUTE}/healthz

Expected:

{"status":"ok"}

Open both URLs in your browser:

The app URL shows a random fortune cookie message
The Argo CD console shows your fortune-cookie Application in Synced / Healthy state — this is your Argo CD instance, scoped entirely to your project

➡️ Move on to Lab 4: Ship It — Validate the GitOps Loop.