View source for DRAFT SDMX-CORE

= Architectire =
== Modules ==
The sdmx-io modules are as follows

<u>Interface Modules</u><br/>
These modules contains Java Interfaces only, no Java classes.  The sdmx-io framework uses Interfaces over implementation classes in order to achieve loose coupling.

 '''fusion-api'''  - contains generic Interfaces that are unrelated to SDMX. Each package in this project is broken down by function, i.e audit, cache, date, email, exception
 '''fusion-api-dao''' - contains Interface definitions for database persistence, not coupled to database platform, but all based on storeage and retrieval of Java Objects
 '''fusion-api-sdmx''' - contains Interfaces for SDMX Information model (SdmxBeans and related), high level Interfaces for SDMX related functions which cross mulitple modules
 '''fusion-api-service''' - contains Interfaces definitions for web services to use - allowing projects the implement web service entry points to not require web service depdenancies

<u>Implementation Modules</u><br/>
These modules contain Java classes which are core to SDMX, they implement Interfaces in the higher api modules
 '''fusion-sdmx-im''' - contains the implementation code for the SDMX Information Model (SdmxBeans and related structures such as Codelists, Concepts, etc)
 '''fusion-core-data''' - contains code to read/write data and generic data related features such as determining series/obs, validation, temporary data stores
 '''fusion-core-sdmx''' - contains core code for structural metadata, including temporary store, cross reference resolution, contains some data and reference metadata features 
 '''fusion-core-structure''' - contains core code for processing structural metadata 
 '''fusion-core-xlsx''' - contains code to read and write structures and data in Excel 

<u>Format Modules</u><br/>
These modules contains Java classes for reading and writing SDMX Structureal Metadata, Reference Metadata, and Data

 '''fusion-sdmx-csv''' - reading and writing SDMX-CSV format
 '''fusion-sdmx-edi''' - reading and writing SDMX-EDI format
 '''fusion-sdmx-json''' - reading and writing SDMX-JSON format
 '''fusion-sdmx-ml''' reading and writing SDMX-XML 

<u>Feature Modules</u><br/>
These modules provide feature specific code
 '''fusion-core-dao''' - contains generic DAO implementations for storing and querying for objects, not coupled to a specific object store, but we use hibernate, mongodb is also an option
 '''fusion-audit''' - audit events and centralised error handling
 '''fusion-sdmx-kafka''' - connecting to and sending/recieving messages to Apache Kafka
 '''fusion-sdmx-publication''' - SDMX Publication Tables: SdmxBean implementations, and buisness logic to materilise table based on definition
 '''fusion-sdmx-reporttemplate''' - Reporting Templates: SdmxBean implementations, and buisness logic to genearte excel workbook from template definition, reading data from workbooks
 '''fusion-sdmx-rest''' - SDMX web services, and additional web service implementations from APIs defined in fusion-api-service
 '''fusion-sdmx-search''' - Lucene search engine for structures
 '''fusion-sdmx-security''' - authentication against LDAP/AD/Fusion Security - contains user definition (SecurityDetailsImpl)
 '''fusion-xl''' - exposes web services required by the FusionXL Excel Pluin

<u>Utility Modules</u><br/>
Utility classes, typically public static classes, the utils projects may organise code by function rather then using the generic packaging structure (api, engine, manager, model, ...)
 '''fusion-utils''' - generic utility classes, not specific to SDMX
 '''fusion-utils-hibernate''' - implementation code to use Hibernate as a means to connect to the DAO
 '''fusion-utils-http''' - calling HTTP web services
 '''fusion-utils-json''' - JSON related utility classes
 '''fusion-utils-mail''' - email utiliity classes
 '''fusion-utils-mongodb'''  - implementation code to use MongoDB a means to store Objects
 '''fusion-utils-sdmx''' - SDMX Specific utilty classes
 '''fusion-utils-spring''' - spring related utility classes
 '''fusion-utils-xlsx''' - reading/writing Excel workbooks related utility classes

== Java Packages ==
Each module is partitioned into Java packages, with the exception of the utility modules, which typically seperate code by its function. 

The generic packages as as follows.

 '''api''' - contains interfaces relevent to the module 
 '''constant''' - contains Java enums and java classes that contain public static constants
 '''engine''' - classes that 'do the work', many are stateless singletons, there are also stateful for example DataReader/WriterEngine 
 '''factory''' - singleton classes that are responisble for generating an engine, typically called by a manager class, factories enable new features to be plugged into the framework
 '''filter'''  - REST web service filters (defined in web.xml) - filters are called before the web service
 '''manager''' - the main entry point for all high level functions, the manager's job is to veryify the request (i.e. a security check) and manage the process of fulfiliing the request by delegating the work to an engine or a DAO, a manager should be a fairly thin layer
 '''model''' - data transfer objects 
 '''service''' (or rest) - web service entry points
 '''util''' - utility classes, typically containing public static methods