Contents

This section of the documentation describes Whitebeam templates and their functionality.

Whitebeam templates are universal "building blocks" that support core services or functions that are common to many e-business processes. As such, the use of Whitebeam templates represents a substantial saving in the complexity, time and cost of developing equivalent back-end functionality in a bespoke system.

While basic JavaScript classes are used to provide utility functions such as image manipulation, HTTP requests, email interface - templates tend to encapsulate a higher level abstraction.

Templates operate as separate processes within the server environment and so do not bloat the process sizes of individual Apache HTTPD processes.

Templates Overview

Whitebeam templates are in effect server-side components that interact with the database and maintain the integrity of the business and data model. Templates are developed in various languages (mostly C++) and interact with the database via SQL.

Presentation Pages interact with the required Whitebeam templates, through simple but powerful methods or APIs, to deploy complex and secure e-business applications that are aligned to the business processes of each client. These exported interfaces are described by the Whitebeam Object Model.

This section on templates gives an overview of template concepts and links to available templates.

Concepts

Presentation pages can execute template services through a number of methods or application programming interfaces. Each Whitebeam template typically supports the following methods or qualified versions of them:

An identifier (ID) is a system assigned value that is guaranteed to be a unique in the context that it is used in the database. Typically, an ID is a positive number starting from 100. Although numeric identifiers are incremented in steps of 2, there is no guarantee that it will be continuous for records that are created in succession by any one client application. Where a method returns an ID, a value of -1 indicates an error.

A marker (...Mkr) typically refers to a system assigned (alpha or numeric) string that indicates the status (or relationship) of a record or to a qualifier of the type of identifier specified in a search request.

Template methods accept and return values of different type. The first five are standard JavaScript types, the last two are Whitebeam defined classes:

Meta-data allows record structures of Whitebeam templates to be extended. An application developer can define a user specific and complex data structures or objects that can be assigned to a meta-data object in an object record and applied to the database. The user-defined object is automatically reconstructed when the record is retrieved.

Whitebeam templates support sophisticated search mechanisms typically through their get() methods. This allows records matching a range of search criteria to be retrieved from the database. It is commonly possible to specify an identifier on which to base the search and to nominate fields in the record structure in which to match up to 4 keywords. The initial implementation is non-case sensitive search.

Special characters % (percent) and _ (underscore) can be used as wildcard characters in a keyword or string search request and can be placed anywhere in a search string. The % character should be placed where any number of characters in that portion of the target string is omitted (e.g. %hite% will find any string containing the consecutive letters ‘hite’ such as ‘This is Whitebeam’). The _ character should be placed where a single character in that position in the target string is omitted (e.g. ‘_hitebeam’ will find any 9 letters ending with ‘hitebeam’ such as ‘Whitebeam’).

The search method returns an iterator object that has the following methods:

getNextRow()     populates the iterator with the next record in the set of search results matching the specified search criteria.

setNextRow()     sets the index of the next record to be retrieved by getNextRow().

The example JavaScript code below shows an iterator loop that retrieves all the records in the result set.

iterator_object = rb.template_object.get( search_object );
while ( iterator_object.getNextRow() )
  write(“Found attribute “+iterator_object.recordID+”<br\>);