DAO Layer

The DAO (Data Access Object) layer in io-oidis-services provides an object-oriented engine for loading, composing, and querying hierarchical JSON-based configuration. Unlike traditional database DAOs, this layer focuses on configuration management — parsing JSONP resource files into typed class instances with support for inheritance, imports, and localization.

Package: io-oidis-services  |  Namespace: Io.Oidis.Services.DAO

Architecture

                 ┌──────────────┐
                 │   BaseDAO    │ ← Core: load, cache, compose
                 └──────┬───────┘
           ┌────────────┼───────────────┐
           ▼                            ▼
    ┌─────────────┐          ┌──────────────────────┐
    │ BasePageDAO  │          │ InstallationRecipeDAO │
    └─────────────┘          └──────────────────────┘
    Page controllers          Installation protocols
    with localization         with download/execute

Supporting Classes

Class	Role
Resources	Extends JsonpFileReader with Extend() and DeepClone() helpers for merging configurations

BaseDAO

BaseDAO is the core class providing object-oriented data parsed from external JSONP resource files. It handles:

• Configuration loading — Asynchronous JSONP file loading via Resources.Load()
• Inheritance — extendsConfig property chains parent configurations
• Imports — imports array references other configuration files as named variables
• Localization — Language-specific configuration overlays (EN, CZ, CN)
• Static caching — Loaded resources are cached to avoid repeated HTTP requests
• Configuration library — Runtime utility functions (Echo, Log, Warning, Error) injected into configuration instances

Key Methods

Method	Description
Load($language, $asyncHandler, $force)	Load the configuration for a given language, resolving inheritance chain and imports
getStaticConfiguration()	Return the raw parsed configuration data
getConfigurationInstance()	Return the configuration as a class instance with inheritance, imports, and library merged
ConfigurationLibrary($value?)	Get or set the library object injected into configuration instances
getParentDAO()	Return the parent DAO from extendsConfig resolution
getImportedDAO($variableName)	Return an imported DAO by its variable name
setConfigurationPath($value)	Set the JSONP file path used as data source
UnloadResource($filePath)	Static method to remove a resource from the global cache

Configuration Hierarchy

When BaseDAO.Load() is called, it:

1. Loads the JSONP file at configurationPath
2. Follows the extendsConfig chain, merging parent data with Resources.Extend()
3. Resolves imports — each imported file is loaded into its own DAO instance
4. Applies localization overlays for the requested language
5. Caches the result in a static ArrayList keyed by file path and language

The getConfigurationInstance() method then composes all these layers into a single prototype-based object where $super references the parent configuration and import variables are accessible as named properties.

Localization Overlays

A configuration file is treated as written in the DAO's default language — LanguageType.EN unless the subclass calls setDefaultLanguage() in its constructor. The overlay mechanics follow from that:

• Load($language) with the default language returns the file as is; no overlay is loaded.
• Load($language) with any other language looks up localization[<language lowercased>] in the base file (e.g. "cz" for LanguageType.CZ) and deep-merges that overlay over a clone of the base. Keys missing in the overlay keep the base value, so an incomplete translation falls back per key.
• The language passed to Load() is not validated against LanguageType — only setDefaultLanguage() is.

A file whose texts are Czech therefore needs setDefaultLanguage(LanguageType.CZ) and localization: {en: "…"}; with the EN default, requesting LanguageType.EN would return the Czech base untouched.

imports and extendsConfig are loaded by DAO instances created through the static getDaoInterfaceClassName(), which returns plain BaseDAO by default. Those instances have the EN default, so a non-EN base language is lost for imported files unless the subclass overrides getDaoInterfaceClassName() to return itself.

On the backend use the Hub Resources handler (getResourcesHandler() override, see MailEngineDAO) so JSONP is read from the file system.

BasePageDAO

Extends BaseDAO for page controller configurations. Adds page-specific accessors:

Method	Description
getPageConfiguration()	Return the typed IBasePageLocalization data
getCacheFilePath()	Return the path used for page static cache loading
getPageTitle()	Return the configured page title
getPageLoadingText()	Return the loading indicator text
getPageLoadingProgressText()	Return the loading progress text
getModelArgs()	Return the BasePanelViewerArgs for the page viewer

InstallationRecipeDAO

Extends BaseDAO for managing multi-step installation protocols. This is the most complex DAO, orchestrating package download, installation, validation, and repair sequences.

Installation Protocols

Protocol Type	Steps
VALIDATE	validate
INSTALL_STATUS	installCondition
INSTALL	installCondition → selectSource → getSource → install → validate
UNINSTALL	installCondition → uninstall
REPAIR	installCondition → selectSource → getSource → repair → validate

Key Methods

Method	Description
getChain()	Return the ordered list of package names to process
getPackage($name)	Resolve and return a fully prepared IInstallationPackage with default handlers for source selection, download, and installation
RunInstallationChain($protocolType)	Execute the full installation chain for a given protocol type, firing progress events
Abort()	Cancel the running chain, aborting active downloads
getEvents()	Return the event interface for subscribing to OnStart, OnChange, OnComplete, and OnError

Event Flow

OnStart → OnChange (per step/package) → OnComplete
                                      → OnError (on failure)

Progress events carry InstallationProgressCode values indicating the current phase: CHAIN_START, STEP_START, DOWNLOAD_START, DOWNLOAD_CHANGE, EXTRACT_START, CLONE, VALIDATED, SKIPPED, CHAIN_END.

Configuration Interfaces

IBaseConfiguration

The minimal interface expected by any JSONP configuration file:

Property	Type	Description
version	string?	Unique version identifier
extendsConfig	string?	Path to parent configuration for inheritance
$interface	string?	DAO parser identifier (e.g. IBasePageConfiguration)
imports	IImports[]?	Array of imported configuration references
localization	ILocalization?	Language-specific overlay paths
noCache	boolean?	Disable resource caching
$super	IBaseConfiguration	Reference to parent configuration instance
Echo, Log, Warning, Error	Functions	Runtime utility functions from the configuration library

IBasePageLocalization

Extends IBaseConfiguration for page controllers:

Property	Type	Description
cacheFile	string?	Path to GUI static cache for fast loading
title	string?	Page title value
loading	string?	Loading indicator text
loadingProgress	string?	Loading progress text

IBaseInstallationRecipe Hierarchy

The installation recipe interface hierarchy defines the package structure:

• IInstallationPackage — A single installable package with name, version, source, and handler methods (validate, install, uninstall, repair)
• IInstallationPackageSource — Platform-specific source URLs (x86/x64) with optional download options
• IInstallationHandler — Callback signature ($status: boolean, $message?: string) => void used by all protocol steps
• IInstallationEnvironment — The full configuration instance with packages map, current block, utilities, and connectors
• IInstallationRecipeNotifications — Localized notification message templates for installation progress

File Structure

source/typescript/Io/Oidis/Services/
├── DAO/
│   ├── BaseDAO.ts                    # Core configuration engine
│   ├── BasePageDAO.ts                # Page controller extension
│   ├── InstallationRecipeDAO.ts      # Installation protocol manager
│   └── Resources.ts                  # JSONP loading + merge helpers
└── Interfaces/DAO/
    ├── IBaseConfiguration.ts         # Core configuration interface
    ├── IBasePageLocalization.ts       # Page localization interface
    ├── IBaseInstallationRecipe.ts     # Installation package interfaces
    └── IInstallationUtils.ts         # System utility interface for installations

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See also: Configuration Overview | JSONP System | HttpProcessor Services