B2B Integration : A Practical Guide to Collaborative E-commerce

Integration Patterns 81
publish interfaces (i.e., they do not support program-level access to
internal business objects).
Key requirements of an API
There are several essential requirements of an API, which makes it
usable for B2Bi applications. Some of them are:
Easy to Use — An API having even the most advanced functions will
not be accepted well by the users, if its interface is not easy to use. The
thumb rule in writing any API should be to make it as easy as possible
for the users to use it. An API should be well supported through proper
documentation and examples.
Language and Platform Independent — The use of APIs in B2Bi
applications will be very limited if their use is bound to a specific
programming language and platform. Two companies trying to integrate
their internal applications using APIs may have the underlying
applications running on different platforms and developed in different
applications. Thus, APIs should be language and platform neutral.
Protect the Underlying Data Sources — The API functions should be
written in such a way so as to allow completely direct access to any
underlying data sources. This requirement is especially important for
B2B applications in which users of one company use APIs to access
data from another company. If the APIs mistakenly provide access to
the data source, the users can maliciously change the data.
Controlled Access — The APIs should provide controlled access to
each user set. Based on the entitlements of the users, the APIs should
provide restricted functionality in terms of invoking functions.
Support for Multiple Data Sources — APIs should provide support for
different types of databases. The APIs should hide the details of each
database format from the calling program.
Limitations of APIs
There are no industry standards for creating an API. Consequently,
the structure and implementation of APIs can differ significantly