Client API

The NRDB offers a number of client applications used to extract and update data.

An advanced Client API has been developed to simplify the developing of these types of client applications. This Client API integrates into all applications which will be using the NRDB database.

All server/client communication is carried out via the HTTP protocol. This protocol is identical to the one used for downloading web pages in i.e. Internet Explorer. In this case, however, the striking difference is that all data are to appear within structures and thus require a Client API to be downloaded.


Quality Control of Data
The Client API offers a solid, comprehensively tested interface comprising internal error management and input data quality control. All data registered or edited via the Client API must be verified by the NPRA feature catalogue’s regulations to ensure that the logical link between technical data is maintained. By employing a dynamic method when integrating the feature catalogue into the Client API, the feature catalogue may be updated on a regular basis and may even be replaced.

Downloading and accessing data
The Client API offers functions for downloading and extracting data from the NRDB server in order to update local sets of data subjected to client modification, to expand on or restrict sets of data, and to update modifications made in NRDB set of data. When the applications work locally on a set of data, functions are used to navigate within the specific set of data, to extract attributes for features, and updating functions are used to create new features, change attribute values etc.

Communication, authentication, and authorization
The Client API automatically manages all communication between the computer application and the NRDB server. This communication is carried out via the HTTP protocol. All security concerns regarding usage of the NRDB database are automatically taken care of by established routines in the Client API and corresponding processes in the NRDB server. In addition to approve NRDB users (authentication), an advanced multi-levelled authorizing system has been developed. This system manages the individual user’s assignments and data access.

Local storage of data for further work
It has been emphasized that the Client API does not need to be online to enable users to access the NRDB database as local storage of extracted technical data is offered to enable client applications to work offline. Users need only to be connected to the NRDB server when loading and logging technical data.

Selecting data
Normally, all working procedures applying the NRDB database will start by specifying technical data and geographical areas being selected. A standard selection dialogue (query Builder) is being offered to ensure that the same selection process is being employed in all applications. This dialogue can be operated by employing a method in the Client API, and it is possible to manage the type of changes the user has access to make within the dialogue. Another important reason as to why applying a standard selection dialogue, is that the dialogue will be comprehensively tested and at all times present up-to-date functionality.

Predefined selection
To speed up the process of defining data selected from the NRDB database, it is possible to predefine a selection of both technical data and geographical areas. This can either be done globally or the individual user can store their personal search in the NRDB database. It is possible to combine several selections and to cut and paste to rapidly define new data selections. When the system administrators configure the selections, specific requirements regarding the use of the selections can be defined.

Logging data
When an NRDB user logs modified or new technical data into the NRDB database, a complete review and quality control of the data is carried out locally in the Client API. The Client API will monitor the modified data and only transmit new or modified data. When the NRDB server receives these changes, a careful verifying process will be carried out to determine whether the transactions are legal with regards to the user rights and access privileges. When this process has been conducted, a consistency control employing data embedded in the feature catalogue and the road network will be performed on the modified data before the changes are finalized.