# System catalogs

{% hint style="warning" %}
**Navixy Repository API is a work in progress.** This documentation is published for preview purposes only and doesn't reflect a stable release. Structure, field names, and behaviors are subject to change.
{% endhint %}

System-defined catalog items that cannot be modified by users.

## Objects

### Module

A system module that groups related functionality and permission scopes. Examples: repo (core), fleet\_management (FSM), iot (devices), reports, billing.

**Implements:** [CatalogItem](https://www.navixy.com/docs/navixy-repository-api/core-api-reference/catalogs/..#catalogitem), [Node](https://www.navixy.com/docs/navixy-repository-api/common#node), [Versioned](https://www.navixy.com/docs/navixy-repository-api/common#versioned), [Titled](https://www.navixy.com/docs/navixy-repository-api/common#titled)

| Field          | Type                                                                                                                 | Description                                                                     |
| -------------- | -------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------- |
| `id`           | `ID!`                                                                                                                | A globally unique identifier.                                                   |
| `version`      | `Int!`                                                                                                               | The version number for optimistic locking.                                      |
| `title`        | `String!`                                                                                                            | The human-readable display name. Can be localized.                              |
| `code`         | `Code!`                                                                                                              | A machine-readable code, unique within the catalog scope.                       |
| `order`        | `Int!`                                                                                                               | The display order within the same level or category.                            |
| `catalog`      | [Catalog](https://www.navixy.com/docs/navixy-repository-api/core-api-reference/catalog-items#catalog)!               | The catalog this item belongs to.                                               |
| `organization` | [Organization](https://www.navixy.com/docs/navixy-repository-api/organizations#organization)                         | The organization that owns this item. Null for system items.                    |
| `meta`         | [CatalogItemMeta](https://www.navixy.com/docs/navixy-repository-api/core-api-reference/catalogs/..#catalogitemmeta)! | Metadata about this item including description, origin, and display properties. |

***

### EntityType

A definition of an entity type in the system.

**Implements:** [CatalogItem](https://www.navixy.com/docs/navixy-repository-api/core-api-reference/catalogs/..#catalogitem), [Node](https://www.navixy.com/docs/navixy-repository-api/common#node), [Versioned](https://www.navixy.com/docs/navixy-repository-api/common#versioned), [Titled](https://www.navixy.com/docs/navixy-repository-api/common#titled)

| Field                    | Type                                                                                                                 | Description                                                                     |
| ------------------------ | -------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------- |
| `id`                     | `ID!`                                                                                                                | A globally unique identifier.                                                   |
| `version`                | `Int!`                                                                                                               | The version number for optimistic locking.                                      |
| `title`                  | `String!`                                                                                                            | The human-readable display name. Can be localized.                              |
| `code`                   | `Code!`                                                                                                              | A machine-readable code, unique within the catalog scope.                       |
| `order`                  | `Int!`                                                                                                               | The display order within the same level or category.                            |
| `catalog`                | [Catalog](https://www.navixy.com/docs/navixy-repository-api/core-api-reference/catalog-items#catalog)!               | The catalog this item belongs to.                                               |
| `organization`           | [Organization](https://www.navixy.com/docs/navixy-repository-api/organizations#organization)                         | The organization that owns this item. Null for system items.                    |
| `meta`                   | [CatalogItemMeta](https://www.navixy.com/docs/navixy-repository-api/core-api-reference/catalogs/..#catalogitemmeta)! | Metadata about this item including description, origin, and display properties. |
| `uuidDiscriminator`      | `String!`                                                                                                            | The 4-character code embedded in UUIDs for entities of this type.               |
| `isCustomizable`         | `Boolean!`                                                                                                           | Whether entities of this type support custom fields.                            |
| `customFieldDefinitions` | \[[CustomFieldDefinition](https://www.navixy.com/docs/navixy-repository-api/custom-fields#customfielddefinition)!]!  | Custom field definitions for entities of this type, ordered by display order.   |

***

### Country

A country reference data item.

**Implements:** [CatalogItem](https://www.navixy.com/docs/navixy-repository-api/core-api-reference/catalogs/..#catalogitem), [Node](https://www.navixy.com/docs/navixy-repository-api/common#node), [Versioned](https://www.navixy.com/docs/navixy-repository-api/common#versioned), [Titled](https://www.navixy.com/docs/navixy-repository-api/common#titled)

| Field          | Type                                                                                                                 | Description                                                                     |
| -------------- | -------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------- |
| `id`           | `ID!`                                                                                                                | A globally unique identifier.                                                   |
| `version`      | `Int!`                                                                                                               | The version number for optimistic locking.                                      |
| `title`        | `String!`                                                                                                            | The human-readable display name. Can be localized.                              |
| `code`         | `Code!`                                                                                                              | A machine-readable code, unique within the catalog scope.                       |
| `order`        | `Int!`                                                                                                               | The display order within the same level or category.                            |
| `catalog`      | [Catalog](https://www.navixy.com/docs/navixy-repository-api/core-api-reference/catalog-items#catalog)!               | The catalog this item belongs to.                                               |
| `organization` | [Organization](https://www.navixy.com/docs/navixy-repository-api/organizations#organization)                         | The organization that owns this item. Null for system items.                    |
| `meta`         | [CatalogItemMeta](https://www.navixy.com/docs/navixy-repository-api/core-api-reference/catalogs/..#catalogitemmeta)! | Metadata about this item including description, origin, and display properties. |
| `alpha2Code`   | `CountryCode!`                                                                                                       | The [ISO 3166](https://www.iso.org/standard/3166.html)-1 alpha-2 country code.  |

***