## POST /api/v2/shared-hosting/{accountId}/domains

**Add hosting addon domain**

Provision an addon domain inside a shared-hosting account that supports cPanel control-panel domain management. Send the full hostname in `domain`; do not pass a raw domain name as `{accountId}` and do not use the retired `subdomain` field. `dir` is optional and must be a safe relative path. If this returns `domain_not_ready`, the domain is registered too recently or its nameservers are not publicly visible yet; for .se and .nu domains this usually resolves within 1-2 hours after registration or a nameserver change, then callers can retry. If this returns `account_not_eligible_cpanel`, the selected hosting account uses HostUp's legacy control panel. Use the control panel SSO link to add the domain manually, or open a support ticket using a slug from `GET /api/v2/support/departments` and ask to migrate the account to a newer cPanel-backed plan.

### Related Endpoints

- `GET /api/v2/shared-hosting/{accountId}/domains`: List hosting domains
- `DELETE /api/v2/shared-hosting/{accountId}/domains`: Remove hosting addon domain
- `GET /api/v2/shared-hosting/{accountId}`: Get shared-hosting account

### Headers

- `Accept`: application/json
- `Authorization`: Bearer YOUR_API_KEY
- Required API scopes: `write:hosting`, `console:services`
- `Content-Type`: application/json

### Parameters

- `accountId` (path, string, required): Public shared-hosting account ID. Get it from GET /api/v2/shared-hosting `data[].id`. Do not invent this value; use the exact ID returned by the referenced API response. Example: `acct_01hxa3b4c5d6e7f8g9h0j1k2m3`

### Request Body

- `domain` (string, required) Example: `shop.example.com`
- `dir` (string, optional): Relative directory under the hosting account. Must not start with `/` and must not contain `..`. Example: `public_html/shop.example.com`

### Request Examples

#### Add addon domain

```bash
curl -X POST "https://cloud.hostup.se/api/v2/shared-hosting/acct_01hxa3b4c5d6e7f8g9h0j1k2m3/domains" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Accept: application/json" \
  -H "Content-Type: application/json" \
  -d '{
    "domain": "shop.example.com",
    "dir": "public_html/shop.example.com"
  }'
```

```json
{
  "domain": "shop.example.com",
  "dir": "public_html/shop.example.com"
}
```

### Response Schema

- `domain` (string, required)
- `kind` (string, required)
  Allowed values: addon
- `documentRoot` (string, required)

### Responses

#### 201 - Addon domain added.
```json
{
  "domain": "shop.example.com",
  "kind": "addon",
  "documentRoot": "public_html/shop.example.com"
}
```

#### 400 - Invalid request body, for example an invalid `domain` hostname or unsafe `dir` path.
```json
{
  "type": "https://developer.hostup.se/errors/invalid_request",
  "title": "Validation failed",
  "status": 400,
  "detail": "The request body failed validation.",
  "code": "invalid_request",
  "instance": "/api/v2/orders",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z",
  "errors": [
    {
      "pointer": "/items/0/eppCode",
      "detail": "`eppCode` is required for this transfer.",
      "code": "missing_required"
    }
  ],
  "extensions": {}
}
```

#### 401 - Unauthorized. Authentication is required.
```json
{
  "type": "https://developer.hostup.se/errors/unauthorized",
  "title": "Unauthorized",
  "status": 401,
  "detail": "Authentication is required.",
  "code": "unauthorized",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z"
}
```

#### 403 - Forbidden. The caller lacks a required scope or does not own the resource.
```json
{
  "type": "https://developer.hostup.se/errors/forbidden",
  "title": "Forbidden",
  "status": 403,
  "detail": "The caller lacks a required scope or does not own the resource.",
  "code": "forbidden",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z"
}
```

#### 404 - Not found. The resource does not exist or is not owned by the caller.
```json
{
  "type": "https://developer.hostup.se/errors/not_found",
  "title": "Not found",
  "status": 404,
  "detail": "The requested resource could not be found.",
  "code": "not_found",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z"
}
```

#### 409 - The domain cannot be added in the current state, for example because it is not DNS-ready yet, conflicts with an existing hosting entry, or the hosting account is not eligible for addon-domain management through this API.
```json
{
  "type": "https://developer.hostup.se/errors/invalid_request",
  "title": "Validation failed",
  "status": 400,
  "detail": "The request body failed validation.",
  "code": "invalid_request",
  "instance": "/api/v2/orders",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z",
  "errors": [
    {
      "pointer": "/items/0/eppCode",
      "detail": "`eppCode` is required for this transfer.",
      "code": "missing_required"
    }
  ],
  "extensions": {}
}
```

#### 429 - Rate limited. Retry after the limit resets. 429 responses include `Retry-After` seconds plus `X-RateLimit-*` headers.
```json
{
  "type": "https://developer.hostup.se/errors/rate_limit_exceeded",
  "title": "Too many requests",
  "status": 429,
  "detail": "Too many requests. Retry after the limit resets.",
  "code": "rate_limit_exceeded",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z"
}
```

#### 500 - Internal error. Retry later or contact support if the issue persists.
```json
{
  "type": "https://developer.hostup.se/errors/internal_error",
  "title": "Internal server error",
  "status": 500,
  "detail": "An unexpected error occurred. Retry later or contact support if the issue persists.",
  "code": "internal_error",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z"
}
```