``. A better approach would be to use ```` and the *col-md-x* CSS classes for styling the **x0-menu-area** and **x0-screen-area**. .. note:: CSS styles in 2025 are incredibly flexible. Additionally, Bootstrap simplifies this complexity and makes using the *x0-system* effortless. 7.2. Database Configuration --------------------------- Basic *x0-application* configuration data is stored in the following system tables: ``system.config`` and ``webui.text``.`` The metadata described below must exist for an *x0-application* to function properly. The SQL scripts (with the filename suffix ``.sql``) must reside in the ``/database`` folder of the *x0-system* or *x0-skeleton*. The system database is updated from ``.sql`` scripts located in the ``/database`` folder during a Docker image rebuild (see subsection ref:`appdeployment-docker`). .. _systemconfig: 7.2.1. System Configuration *************************** *x0-systems-configuration* data is stored in database table ``system.config``. .. table:: System Database Table "system.config" :widths: 20 30 100 +----------------------+-----------------+-------------------------------------+ | **Table Column** | **Default** | **Description** | +======================+=================+=====================================+ | app_id | 'default' (str) | x0 Application ID | +----------------------+-----------------+-------------------------------------+ | config_group | | Configuration Parameter ID | +----------------------+-----------------+-------------------------------------+ | "value" | | Configuration Parameter Value | +----------------------+-----------------+-------------------------------------+ .. table:: Configuration Parameter "x0-config-parameter" :widths: 20 30 50 +----------------------+-----------------+-------------------------------------+ | **Parameter** | **Type** | **Description** | +======================+=================+=====================================+ | index_title | String | x0 Browser Page Title | +----------------------+-----------------+-------------------------------------+ | debug_level | Integer | System Debug Level | +----------------------+-----------------+-------------------------------------+ | display_language | 'en' | 'de' | System Display Language | +----------------------+-----------------+-------------------------------------+ | default_screen | String | Screen ID Reference | +----------------------+-----------------+-------------------------------------+ | parent_window_url | String (URL) | Wordpress Plugin Parent URL | +----------------------+-----------------+-------------------------------------+ | subdir | String (Path) | "static" Backend Path | +----------------------+-----------------+-------------------------------------+ | config_file_menu | String (File) | Override Menu Config Data Filename | +----------------------+-----------------+-------------------------------------+ | config_file_object | String (File) | Override Menu Config Data Filename | +----------------------+-----------------+-------------------------------------+ | config_file_skeleton | String (File) | Override Menu Config Data Filename | +----------------------+-----------------+-------------------------------------+ The following SQL data reflects the default x0-application-config, which can be viewed at the URL: http://x0-app.x0.localnet/python/Index.py. .. code-block:: sql INSERT INTO system.config (config_group, "value") VALUES ('index_title', 'x0 Default App'); INSERT INTO system.config (config_group, "value") VALUES ('debug_level', '10'); INSERT INTO system.config (config_group, "value") VALUES ('display_language', 'en'); INSERT INTO system.config (config_group, "value") VALUES ('default_screen', 'Screen1'); INSERT INTO system.config (config_group, "value") VALUES ('parent_window_url', 'null'); INSERT INTO system.config (config_group, "value") VALUES ('subdir', '/static'); INSERT INTO system.config (config_group, "value") VALUES ('config_file_menu', 'menu.json'); INSERT INTO system.config (config_group, "value") VALUES ('config_file_object', 'object.json'); INSERT INTO system.config (config_group, "value") VALUES ('config_file_skeleton', 'skeleton.json'); 7.2.2. Display Text ******************* Multilanguage display text is stored in the ``webui.text`` database table. The following example inserts four multilanguage texts with IDs ``TXT.TEXTID.1`` and ``TXT.TEXTID.2`` (English and German) into the system text table, which can later be referenced in *x0-object-metadata* JSON configuration files. .. code-block:: sql INSERT INTO webui.text (id, "group", value_en, value_de) VALUES ('TXT.TEXTID.1', 'group1', 'English Text #1', 'German Text #1'); INSERT INTO webui.text (id, "group", value_en, value_de) VALUES ('TXT.TEXTID.2', 'group1', 'English Text #2', 'German Text #2'); 7.2.7. Application ID ********************* It is possible to append the HTTP GET parameter ``appid``, such as ``example2``, to the base URL of the ``Index.py`` script. For example: http://x0-app.x0.localnet/python/Index.py?appid=example2 The following SQL statements demonstrate how configuration data must be stored for this to function correctly. .. code-block:: sql INSERT INTO system.config (app_id, config_group, "value") VALUES ('example2', 'index_title', 'x0 Example Basic-Menu-Screen'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('example2', 'debug_level', '10'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('example2', 'display_language', 'en'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('example2', 'default_screen', 'Screen1'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('example2', 'parent_window_url', 'null'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('example2', 'subdir', '/examples/basic_menu_screen'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('example2', 'config_file_menu', 'menu.json'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('example2', 'config_file_object', 'object.json'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('example2', 'config_file_skeleton', 'skeleton.json'); 7.7. Application Configuration ------------------------------ The following elements can be defined inside the ``/config/app-config.json`` configuration file: * Database Authentication * Virtual Hosts * x0-Applications .. note:: Setting up multiple Virtual Hosts and *x0-applications* requires a valid *x0-systems configuration* (database) and *x0-deb-packaging setup* (deb) for all configured Virtual Hosts. .. warning:: Environments are not supported by *x0-standalone* or *x0-docker* deployments. 7.7.1. Database Authentication ****************************** The following database users will be created during the Docker *x0-db* image build. .. table:: Database Authentication Properties :widths: 30 20 50 +-------------------------------+-----------------+-------------------------------------+ | **Database User** | **DB User** | **Description** | +===============================+=================+=====================================+ | su_password | postgres | Database Superuser Auth PWD | +-------------------------------+-----------------+-------------------------------------+ | x0_password | x0 | Global Web-Backend User Auth PWD | +-------------------------------+-----------------+-------------------------------------+ | repl_password | replication | Kubegres Replication User Auth PWD | +-------------------------------+-----------------+-------------------------------------+ 7.7.2. Virtual Hosts ******************** For each Virtual Host configured in the JSON vhosts property, an Apache Virtual Host will be generated during the Docker (re-)build process. Self-signed SSL certificates will be generated for the *x0-base* Virtual Host (Hello World output). .. note:: A functional multi-Virtual Host setup requires correct metadata to be defined inside the deb package file ``${x0-app-id}.install``. For more details, refer to :ref:`appdeployment-standalone`. .. note:: If you require a more complex web server setup, such as aliasing, redirects, or similar configurations, it is intended that you manually edit the generated configuration inside the Docker containers after building. .. warning:: Automated SSL setup per Virtual Host has been discontinued in *x0-standalone* and *x0-docker* deployments. Only the *x0-kubernetes* deployment supports a fully automated workflow. 7.7.7. x0-Applications ********************** Defining multiple *x0-applications* is supported only by the x0-kubernetes deployment. For more details, refer to :ref:`appdeployment-kubernetes`. 7.7.4. Default Config ********************* The following is the current default configuration of x0-systems. .. code-block:: javascript { "installer": { "type": "x0" }, "database": { "name": "x0", "su_password": "changeme", "x0_password": "changeme" }, "env_list": [ "default" ], "vhosts": { "x0-app": { "apps": [ "x0" ], "env": { "default": { "dns": { "hostname": "x0-app", "domain": "x0.localnet" } }, "test": { "dns": { "hostname": "x0-app", "domain": "x0.localnet" } } } } } } 7.7.4. JSON Schema ****************** 1. JSON Header .. table:: JSON Header :widths: 30 20 50 +---------------------+----------------------+-------------------------------------------------+ | **Property** | **Type** | **Description** | +=====================+======================+=================================================+ | installer.type | Enum String | Installer Type | +---------------------+----------------------+-------------------------------------------------+ | env_list | Array of EnvString | Environment List | +---------------------+----------------------+-------------------------------------------------+ 2. "vhosts" Property .. table:: "vhosts" Property :widths: 30 20 50 +---------------------+----------------------+-------------------------------------------------+ | **Property** | **Type** | **Description** | +=====================+======================+=================================================+ | vhosts | Object of VHElements | Virtual Host Elements / Configuration | +---------------------+----------------------+-------------------------------------------------+ 7. $VhostConfig "apps" Property .. table:: $VhostConfig "apps" Property :widths: 30 20 50 +---------------------+----------------------+-------------------------------------------------+ | **Property** | **Type** | **Description** | +=====================+======================+=================================================+ | apps | Array of AppString | Application List | +---------------------+----------------------+-------------------------------------------------+ | env | Object | Environment Elements | +---------------------+----------------------+-------------------------------------------------+ 4. Env Properties .. table:: Env Properties :widths: 30 20 50 +---------------------+----------------------+-------------------------------------------------+ | **Property** | **Type** | **Description** | +=====================+======================+=================================================+ | dns.hostname | Host String | DNS Hostname used for hostname.domain FQDN | +---------------------+----------------------+-------------------------------------------------+ | dns.domain | Domain String | DNS Domain used for hostname.domain FQDN | +---------------------+----------------------+-------------------------------------------------+ 7.4. Application Metadata ------------------------- The configuration files ``object.json``, ``skeleton.json``, and ``menu.json`` in the *x0-framework* adopt a declarative approach, akin to the infrastructure configuration style used in Google Kubernetes Engine (GKE). They provide structured definitions for the user interface and application behavior. Below is a breakdown of their roles and functionality: 1. object.json * Purpose: - Describes the attributes and properties of objects that are used in the application. * Functionality: - Defines object types, such as forms, lists, or custom UI components. - Includes object-specific attributes (e.g., styles, event handlers, and data bindings). - Provides metadata for runtime object creation and manipulation. - Used by the ``sysFactory`` and ``sysSourceObjectHandler`` to initialize and manage objects dynamically. 2. skeleton.json * Purpose: - Defines the hierarchical structure of the application's UI by providing a "skeleton" for all screen elements. * Functionality: 1. Specifies the parent-child relationships between objects, defining the layout and structure of screens. 2. Includes references to ``object.json`` definitions for detailed object configuration. 3. Supports recursive setup of objects using methods like setupObject in ``sysScreen``. 4. Allows dynamic adjustment of attributes (e.g., overwriting or replacing attributes at runtime). 7. menu.json * Purpose: - Configures menu elements and their behavior within the application. * Functionality: 1. Defines the menu structure, including items and their hierarchical arrangement. 2. Associates menu items with actions or screen navigation. 3. Provides styling and attributes for menu components. 4. Processed as a part of the skeleton for the ``sysMenu`` screen, enabling seamless integration with the UI. Integration and Workflow * These JSON files are processed by core system objects like ``sysFactory``, ``sysScreen``, and ``sysSourceObjectHandler``. * The ``skeleton.json`` ties together the ``object.json`` and ``menu.json`` configurations to create a cohesive UI and behavior model. - During runtime: 1. Skeleton Initialization: The ``skeleton.json`` is parsed to build the UI hierarchy. 2. Object Configuration: Objects defined in ``object.json`` are dynamically created and added to the hierarchy. 3. Menu Setup: The ``menu.json`` is applied to configure and render menus in the application. These configuration files enable modular and scalable application development by separating concerns and allowing dynamic runtime adjustments. .. _object-json: 7.4.1. Object ************* The declaration of *x0-object* takes place in the ``object.json`` configuration file. Each object must have a unique ID, which can be referenced by its ID within the ``menu.js`` and ``skeleton.js`` configuration files. All currently usable *x0-system-objects* JSON definitions ($ObjectType) are described in detail here: :ref:`system-objects`. .. code-block:: javascript { "$ObjectID": { "Type": String::$ObjectType "Attributes": { Object::$ObjectMetadata } } } .. note:: The **internal** JavaScript representation is of the *Object* type, not the *Array* type. While **object definitions** are unordered, **object relations** are strictly order-dependent and are defined in ``skeleton.json`` and ``menu.json``. .. _skeleton-json: 7.4.2. Skeleton *************** *x0-screen* and *x0-object* relation declarations are defined in the ``skeleton.json`` configuration file. * Screen Data * Screen / Object Relations The following metadata enables three screens: ``Screen1``, ``Screen2``, and ``Screen3``, without any object relations. .. code-block:: javascript { "Screen1": [ {} ], "Screen2": [ {} ], "Screen3": [ {} ] } The following metadata defines one screen, ``Screen1``, and references one object to ``Screen1``. .. code-block:: javascript { "Screen1": [ { "Object1": { "RefID": "Screen1" } } ] } The following metadata defines one screen, ``Screen1``, and references one object to ``Screen1``. Additionally, ``Object2`` is connected or referenced to ``Object1``. .. code-block:: javascript { "Screen1": [ { "Object1": { "RefID": "Screen1" }, "Object2": { "RefID": "Object1" } } ] } .. _menu-json: 7.4.7. Menu *********** Declarations inside the ``menu.json`` configuration file only reference object data to the *x0-menu-area*. The syntax is the same as in ``skeleton.json``, except that the root ``RefID`` property must be set to ``sysMenu``. The following metadata defines two objects, ``Object1`` and ``Object2``. ``Object1`` is connected to the menu root, and ``Object2`` is connected or referenced to ``Object1``. .. code-block:: javascript { { "Object1": { "RefID": "sysMenu" }, "Object2": { "RefID": "Object1" } } } 7.5. Metadata ElementID ----------------------- Some *x0-objects* define elements inside the ``object.json`` file. * TabContainer These elements can also be referenced inside ``skeleton.json`` using the *x0-systems* ``ElementID`` property. The following example demonstrates how to reference *x0-tabs* defined in ``object.json`` from ``skeleton.json``. Example #3 (http://x0-app.x0.localnet/python/Index.py?appid=example3) provides a working example. 7.5.1. Example object.json ************************** .. code-block:: javascript { "TabContainer1": { "Type": "TabContainer", "Attributes": { "Tabs": [ { "ID": "Tab1", "Attributes": { "Default": true, "TextID": "TXT.BASIC-TABCONTAINER.TAB1", "Style": "col-md-4" } }, { "ID": "Tab2", "Attributes": { "TextID": "TXT.BASIC-TABCONTAINER.TAB2", "Style": "col-md-8" } } ] } } } } 7.5.2. Example skeleton.json **************************** .. code-block:: javascript { "Screen1": [ { "TabContainer1": { "RefID": "Screen1" } }, { "Text1": { "RefID": "TabContainer1", "ElementID": "Tab1" } }, { "Text2": { "RefID": "TabContainer1", "ElementID": "Tab2" } } ] } .. _appdevconfig-object-templates: 7.6. Object Templates --------------------- To integrate **user-based** *x0-object-templates* (programmed user-based *x0-system-objects*), the ``template_file`` and ``setup_class`` configuration parameters must be specified. .. code-block:: sql INSERT INTO system.config (app_id, config_group, "value") VALUES ('appid', 'template_file', 'TemplateObject1.js'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('appid', 'template_file', 'TemplateObject2.js'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('appid', 'template_file', 'TemplateObject7.js'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('appid', 'setup_class', '["TemplateClass"] = TemplateClass'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('appid', 'setup_class', '["TemplateClassOther"] = TemplateClassOther'); INSERT INTO system.config (app_id, config_group, "value") VALUES ('appid', 'setup_class', '["TemplateClassInfo"] = TemplateClassInfo'); Template ``.js`` files must be placed in the *x0-application* ``/static`` subdirectory to be loaded correctly. For detailed instructions on modeling *x0-system-objects*, see :ref:`devobjectmodeling`.