# Deployment — server provisioning, CD, TLS

Frontend deployment plus API-domain edge configuration. The backend service is a
separate developer's responsibility. API hostnames are separate reverse proxies
and return `502` until their configured upstream exists (production currently
defaults to `https://127.0.0.1:445`).

**Multi-tenant, one bundle.** Every customer domain is served by the same build. The SPA resolves its tenant from the `Host` header ([BACKEND-HANDOFF §1a](backend/BACKEND-INTEGRATION.md)). One deploy updates every domain simultaneously — there is no per-tenant build and no per-tenant deploy.

The SPA derives one API origin from the storefront's base domain:
`example.com`, `store1.example.com`, and `www.example.com` all use
`api.example.com`. Tenant identity still comes from the complete storefront
host; tenant subdomains do not create additional API DNS names.

---

## 1. Files

| Path | Purpose |
|---|---|
| `scripts/deploy/server-setup.sh` | One-time server provisioning. Idempotent. Run as root. |
| `scripts/deploy/add-domain.sh` | Attach one domain + issue TLS. Run per domain, as root, after DNS resolves. |
| `scripts/deploy/configure-api-domain.sh` | Configure shared `api.<base domain>` TLS, storefront-origin CORS, backend proxy, and JSON bootstrap verification. |
| `.github/workflows/deploy.yml` | CD: build → upload → atomic swap → verify. Triggers on push to `main`. |

---

## 2. Layout on the server

```
/srv/marketplaces/
├── releases/
│   ├── a1b2c3d4e5f6/frontend/    <- one directory per deployed commit
│   └── ...                        (last 5 kept)
└── current -> releases/a1b2c3d4e5f6
```

nginx root is `/srv/marketplaces/current/frontend`. Activation is a symlink swap, so no request is ever served from a half-written directory, and a rollback is a symlink change rather than a rebuild.

**On the current production host there is one extra hop.** That server predates
`server-setup.sh` and was provisioned by hand, so instead of the catch-all vhost
it has per-domain configs (`gorbushka.conf`, `dexarmarket.conf`,
`gorbushka-admin.conf`, `gorbushka-landing.conf`) whose `root` is
`/var/www/dexarmarket/browser`. That path is itself a symlink:

```
/var/www/dexarmarket/browser -> /srv/marketplaces/current/frontend
```

so the release/`current` model above still holds and the workflow needs no
per-host special-casing. Until 2026-08-22 `browser` pointed straight at one
pinned release directory with no `current` in between, which is why two
successfully-uploaded releases sat unserved.

---

## 3. First-time setup

### 3.1 Generate a CI deploy key

On your machine, **not** on the server:

```bash
ssh-keygen -t ed25519 -C "ci@marketplaces" -f ./marketplaces_deploy -N ""
```

Two files result. `marketplaces_deploy.pub` goes to the server; `marketplaces_deploy` (private) goes into CI secrets and nowhere else.

### 3.2 Provision the server

Copy `scripts/deploy/` to the server and run:

```bash
sudo bash server-setup.sh --pubkey "$(cat marketplaces_deploy.pub)"
```

This installs nginx + certbot, creates a **key-only** `deploy` user with no
password, writes the catch-all nginx config, opens 80/443/OpenSSH in ufw, and
installs a root-owned, argument-validating API-domain helper. The deploy user may
run that helper and reload nginx, but cannot replace the helper.

It also applies host hardening (added 2026-08-21, FH-D.3) — three drop-in files,
so a re-run replaces its own config and never edits a distro file in place:

| File | Effect |
|---|---|
| `/etc/ssh/sshd_config.d/10-marketplaces-hardening.conf` | Password and keyboard-interactive auth off, root key-only, no agent/X11 forwarding, `MaxAuthTries 3`, 30 s login grace |
| `/etc/fail2ban/jail.d/marketplaces.local` | `sshd`, `nginx-http-auth`, `nginx-bad-request` jails — 5 failures in 10 min, 1 h ban |
| `/etc/sysctl.d/99-marketplaces-hardening.conf` | No redirects or source routing, reverse-path filtering, SYN cookies, forwarding off, restricted kernel pointers and dmesg |

Both accounts on this host are key-only by construction, so disabling password
auth cannot lock anyone out — it only closes unlimited guessing against a
credential nobody intended to exist. The script runs `sshd -t` before reloading
and removes its own drop-in if the test fails, because a bad sshd config taking
effect on a remote box is how people lock themselves out permanently.

Confirm after provisioning:

```bash
sudo fail2ban-client status sshd
sudo sshd -T | grep -E 'passwordauthentication|permitrootlogin|maxauthtries'
```

Verify before continuing:

```bash
curl -I http://<server-ip>/health
```

Expect `200`. A placeholder page is served until the first real deploy.

### 3.3 Capture the host key

```bash
ssh-keyscan -H <server-ip>
```

The output is the `DEPLOY_KNOWN_HOSTS` secret. Pinning it means a rebuilt or impersonated server fails the deploy instead of being trusted silently.

### 3.4 Add CI secrets

Required for every deploy:

| Secret | Value |
|---|---|
| `DEPLOY_HOST` | server IP or hostname |
| `DEPLOY_USER` | `deploy` |
| `DEPLOY_SSH_KEY` | contents of the **private** key file |
| `DEPLOY_KNOWN_HOSTS` | output of `ssh-keyscan -H <server-ip>` |

Required **only** when running the workflow with `reconcile_api_domains` on
(§4.6) — a normal release deploy never reads these:

| Secret | Value |
|---|---|
| `STOREFRONT_DOMAINS` | space-separated full hosts, e.g. `gorbushka.market store1.example.com` |
| `CERTBOT_EMAIL` | operations email used for Let's Encrypt |
| `BACKEND_UPSTREAM` | optional; defaults to `https://127.0.0.1:445` |

When that step does run, point each base domain's shared API hostname at the
server first. For `gorbushka.market` and `store1.gorbushka.market`, only
`api.gorbushka.market` is required. The workflow deduplicates
`STOREFRONT_DOMAINS` by base domain and deliberately stops before release
activation if DNS, certificate issuance, nginx validation, or the JSON
`/bootstrap` check fails.

### 3.5 Deploy

Push to `main`, or run the workflow manually with a ref. The workflow refuses to swap the symlink unless the uploaded release contains an `index.html`, so a failed upload leaves the previous release serving.

---

## 4. Domains and TLS — dynamic by default

Domains arrive continuously: one today, five tomorrow. Nothing here requires a person per domain.

**HTTP already needs zero configuration.** The nginx catch-all serves *any* `Host`, and the SPA resolves its tenant from that header. Point a domain's A record at the server and it works over port 80 immediately. Only TLS needs a certificate per name — that is the whole problem this section solves.

Two mechanisms, used together:

### 4.1 Wildcard — tenants on our own apex

One certificate covers every `<slug>.<apex>`. A new tenant subdomain is then live over HTTPS the moment DNS resolves, with **no certificate work at all**.

```bash
sudo bash setup-wildcard-tls.sh \
  --apex marketplaces.example.com \
  --email ops@example.com \
  --dns cloudflare --creds /root/cloudflare.ini
```

Wildcards require DNS-01 validation, so certbot must write a `_acme-challenge` TXT record. With a provider plugin (`cloudflare`, `route53`) renewal is unattended. `--dns manual` works but prompts for a TXT record at **every** renewal — fine to prove the setup out, not acceptable as a steady state.

**Hostinger has no certbot plugin.** If DNS lives there: either move DNS to a provider that has one (Cloudflare is free, minutes of work), or drive issuance from the [Phase 9](backend/BACKEND-INTEGRATION.md) domain-automation API once it exists.

### 4.2 Reconciler — tenants on their own domains

A wildcard cannot cover a customer's own domain. `sync-domains.sh` runs on a 10-minute timer and reconciles the live set against a desired list:

- issues certificates for domains that lack one
- skips domains whose certificate has more than 30 days left
- skips subdomains already covered by `WILDCARD_APEX`
- leaves domains alone while their DNS has not propagated yet, and retries next tick
- disables server blocks for domains removed from the source — **without deleting the certificate**, so re-adding one later is instant
- caps issuance per run, so a misconfigured source cannot burn the weekly ACME budget in a single pass

Configure `/etc/marketplaces/domains.env`:

```bash
DOMAINS_SOURCE=file:/etc/marketplaces/domains.txt
CERTBOT_EMAIL=ops@example.com
MAX_ISSUE_PER_RUN=10
```

Then:

```bash
sudo systemctl enable --now marketplaces-domains.timer
sudo /srv/marketplaces/bin/sync-domains.sh --dry-run   # see the plan, change nothing
```

Adding a domain becomes: append a line to `/etc/marketplaces/domains.txt` (or add the row in the backend registry), point DNS, wait one tick.

### 4.3 Backend-driven, once Phase 9 ships

Point the reconciler at the registry instead of a file and the loop closes — `MarketplaceDomain` already carries exactly the statuses this needs (`planned → dns_pending → ssl_pending → active → failed`):

```bash
DOMAINS_SOURCE=https://api.example.com/api/admin/v2/domains
DOMAINS_API_TOKEN=...
```

The script accepts a bare JSON array of hostnames, or objects with `domain` + `status`, in which case it acts only on `active` rows. **A fetch failure aborts the run rather than reading as "remove every domain."**

### 4.4 One-off

For a single domain, outside the reconciler:

```bash
sudo bash add-domain.sh shop.example.com --email ops@example.com --with-www
```

### 4.5 API domains in CD are opt-in

The deploy workflow's **Reconcile tenant API domains** step is gated behind the
`reconcile_api_domains` input and is **off for push-triggered deploys**.

`configure-api-domain.sh` writes `/etc/nginx/sites-available/api.<domain>` and
enables it. The API vhosts on the current production host were created by hand
under different filenames (`gorbushka-api.conf`), so running the helper there
produces a *second* server block for a `server_name` that already has one, and
re-runs certbot against a live API — on every deploy. Shipping frontend files
needs none of that.

Turn it on from the workflow-dispatch form only when standing up a **new** base
domain. Before the first such run, reconcile the naming: either delete the
hand-made vhost and let the helper own the name, or leave the step off and keep
managing API domains manually.

### 4.6 Verify

```bash
curl -I https://shop.example.com/health
sudo certbot certificates
journalctl -u marketplaces-domains.service --since "1 hour ago"
```

---

## 5. Rollback

```bash
ssh deploy@<server-ip>
ls -1dt /srv/marketplaces/releases/*/     # newest first
ln -sfnT /srv/marketplaces/releases/<sha> /srv/marketplaces/current.new
mv -Tf /srv/marketplaces/current.new /srv/marketplaces/current
sudo systemctl reload nginx
```

Only the last 5 releases are retained. Older ones need a rebuild from the tag.

The production host reaches releases through `/var/www/dexarmarket/browser ->
/srv/marketplaces/current/frontend` (§2), so moving `current` is all a rollback
needs there too — do not repoint `browser` at a release directly, or the next
deploy's swap will silently stop taking effect.

---

## 6. Operational checks

```bash
curl -I http://<host>/health                    # 200 from nginx
readlink -f /srv/marketplaces/current           # which commit is live
sudo nginx -t                                   # config valid
systemctl status nginx certbot.timer            # both active
sudo tail -f /var/log/nginx/marketplaces.error.log
```

---

## 7. Known limits

- **`/api/` 502s until the backend runs.** Expected. nginx proxies to `127.0.0.1:8080`; nothing listens there yet.
- **No staging environment.** `main` goes straight to production. Adding one means a second server plus a `staging` branch trigger.
- **No smoke test beyond HTTP 200.** The verify step confirms nginx serves the shell, not that the app boots. A real check needs the E2E harness from Track Q.
- **Caching.** `index.html` is `no-store`; hashed assets are `immutable` for a year. A deploy therefore takes effect on the next page load, with no cache purge.
