AqBanking Documentation Main Page

4.2.4

This is AqBanking, a modular library for Online Banking and related tasks.

This library was designed by Martin Preuss<martin@aquamaniac.de> to provide a generic way for applications to use Online Banking (e.g. HBCI), and to import/export financial data (such as OFX, SWIFT, DTAUS). It is written in C (see API for Applications).

If you are writing an application and want to use AqBanking's features, there are two possibilities:

• Use the "Im/Exporter Layer API", which requires the least coding effort on the application side. See Online Banking,

• Or you can use the "Main Interface API" (also called "High level API" sometimes), which offers the highest flexibility by its access to AB_JOB objects but requires slightly more coding effort. See Main Interface, and there is also a full introduction into the program flow of that interface: Introduction into application programming with AqBanking

A general Note: All strings exchanged from and to AqBanking are expected in UTF-8 encoding unless stated otherwise. Please do not pass Latin-1 strings (i.e. with latin1-Umlauts) into AqBanking or expect the returned strings (which might be translated into German in UTF-8) in that way. For converting UTF-8 into or from other encodings, see the system function iconv(3) in iconv.h.

Features

AqBanking is very modular. It simply provides the means to manage online accounts and to import/export financial data. AqBanking itself does not implement the actual online banking protocols -- this is done in extra plugins which serve as backends/providers. This library is organized in multiple layers:

• API for Applications: This contains the complete API to be used by applications (see API for Applications). It is subdivided into several groups and includes (among other things):
  • Managing Backends/Providers
  • Managing Accounts
  • Accepting AB_JOB objects for online banking jobs from the application and sending them to the corresponding provider

• Simplified API: This layer offers an even simpler API to applications, where the calls to all lower layers are combined, and the application will not deal with AB_JOB objects. This may be useful when adding AqBanking support to applications which have not been designed to work with AqBanking in the first place (see Simplified API)

• API for Backends This level is represented by the function group API for Backends). These functions should not be accessed by an application; instead, they are accessed by plugins. The plugins (e.g. AqHBCI) implement the Provider functions which actually implement the online banking functionality. ("Provider" is simply another word for "backend".) The API has been designed to be as wide open as possible, and currently it is used by plugins for HBCI, OFX Direct Connect, YellowNet, DTAUS and GeldKarte providers.

For the backends/providers, AqBanking provides callbacks for some simple user interaction functions, independently of the actual graphical or text frontend. (see Backend Objects) This has the additional advantage that any new backend/provider will then immediately be supported by all applications.