Deploy

---
name: deploy
description: "This skill should be used when deploying containerized applications to remote servers. It builds Docker images, pushes to GHCR, and deploys via SSH with health verification."
---

# Deploy Skill

Deploy a containerized application to a remote server via Docker and SSH.

## Environment Variables

| Variable | Required | Description | Example |
|----------|----------|-------------|---------|
| `DEPLOY_HOST` | Yes | SSH target (user@host) | `root@203.0.113.10` |
| `DEPLOY_IMAGE` | Yes | GHCR image path | `ghcr.io/org/app` |
| `DEPLOY_HEALTH_URL` | No | Health check endpoint | `http://203.0.113.10:3000/health` |
| `DEPLOY_CONTAINER` | No | Container name (default: image basename) | `myapp` |
| `DEPLOY_DOCKERFILE` | No | Dockerfile path (default: `./Dockerfile`) | `./docker/Dockerfile.prod` |

For first-time server setup, see [hetzner-setup.md](./references/hetzner-setup.md).

## Phase 0: Validate

Check prerequisites before starting the build.

Run these checks as separate Bash commands:

1. Verify `DEPLOY_HOST` is set: `printenv DEPLOY_HOST` (must produce output)
2. Verify `DEPLOY_IMAGE` is set: `printenv DEPLOY_IMAGE` (must produce output)
3. Verify Docker daemon: `docker info > /dev/null 2>&1`
4. Verify SSH connectivity: `ssh -o ConnectTimeout=5 -o BatchMode=yes <deploy-host> "echo OK"` (replace `<deploy-host>` with the actual DEPLOY_HOST value)
5. Verify Dockerfile exists: `test -f ./Dockerfile` (or the DEPLOY_DOCKERFILE path if set)

If any check fails, stop and report the error. Do not proceed to Phase 1.

## Phase 1: Plan

Show the deployment summary and ask for confirmation.

Use the **AskUserQuestion tool** to present:

**Question:** "Deploy this configuration?"

**Options:**
1. **Deploy** -- Proceed with build and deployment
2. **Cancel** -- Abort deployment

Display before asking:

```text
Deployment Plan
  Image:      <DEPLOY_IMAGE>:<git-short-sha>
  Target:     <DEPLOY_HOST>
  Container:  <DEPLOY_CONTAINER or image basename>
  Dockerfile: <DEPLOY_DOCKERFILE or ./Dockerfile>
  Health URL: <DEPLOY_HEALTH_URL or none>
```

Resolve `<git-short-sha>` by running `git rev-parse --short HEAD`.

If the user selects Cancel, stop execution.

## Phase 2: Execute

Run [deploy.sh](./scripts/deploy.sh) to build, push, and deploy:

```bash
bash ./plugins/soleur/skills/deploy/scripts/deploy.sh
```

The script handles:
1. Build Docker image tagged with git SHA and `:latest`
2. Push both tags to GHCR
3. SSH to remote host: pull image, stop old container, start new container

## Phase 3: Verify

After deployment completes, verify the service is running.

**If `DEPLOY_HEALTH_URL` is set:**

The deploy script runs a health check (5 attempts, 3s apart).

If the health check fails:

```text
Health check failed. Debug with:
  ssh <DEPLOY_HOST> "docker logs <container-name> --tail 50"
```

**If `DEPLOY_HEALTH_URL` is not set:**

Report deployment as complete without health verification:

```text
Deployed <git-short-sha> to <DEPLOY_HOST>
No health URL configured -- skipping verification.
```

## Important Rules

- Never hardcode secrets in the deploy script. Use environment variables.
- Never deploy without user confirmation (Phase 1 gate).
- The script uses `set -euo pipefail` -- any command failure aborts the deployment.
- Container restart uses stop+pull+start, not `docker restart`, to ensure the new image is used.