This documentation:
Global services are applications that provide useful functionality that is frequently required by end-users, external applications or Knowledge Management components. Unlike repository services, global services are often independent of repositories. They normally do not need to access repositories or interact with repository managers.
An essential characteristic of global services is that only one
instance of a global service is instantiated at runtime. This
instance is used by all components. In contrast, repository services can
be instantiated several times at runtime. This means that different
repository managers can have their own instance of a repository service.
As global services are independent of repositories, they do not have to
be explicitly assigned to repositories in the configuration. They simply
have to be registered with a unique ID and implementation class.
The following sections describe the availalbe services in alphabetical order.
The action inbox service manages the KM inbox. Basically it provides a link between applications and the inbox of users. Applications can use the service to:
The main task of the service is to route the messages from the application to the correct inbox and to organize the entries in the inbox into predefined categories. In addition, the service enables users to process messages by giving them direct access to the functions of the associated application. To process a message, a user simply needs to choose an action offered in the inbox. The action is then directed back to the application which presents the user with the appropriate functions. It is the task of the service to provide the direct link between the message and the functions of the application.
Further Information
See the Javadoc package description com.sapportals.wcm.service.actioninbox for:
Provides logging functions for services and applications using the Knowledge Management Framework.
You can use the cache service to create and manage a cache. Features of the service allow you to define the properties of a cache, to add or remove entries from it or to access information about it. The purpose of a cache is primarily to speed up access to resources. If resources are stored on a slow medium or take long to access via the network, placing them in the cache speeds up access.
When an object is added to the cache, a pointer referencing the object is set. The object itself resides in memory. Setting the pointer protects the object against the garbage collection mechanism which deletes any objects from memory that are not referenced by a pointer. If the garbage collector registers that a pointer exists it does not delete the object from memory.
The Knowledge Management application allows users to check out resources to edit them with a PC application on the local host. The checkout service stores and provides all information related to this checkout process. It does not execute the checkout operation itself, but sets the status and keeps track of information related to the operation. For example, it can determine the host and path to a checked out resource or find out whether users are allowed to checkout resources.
The crawler service provides functions to create and manage crawlers. Crawlers are used to determine all the resources contained in a Content Management (CM) repository and to obtain references to them. The behavior of crawlers can be controlled in various ways. For example, they can be instructed to find resources that match certain conditions.
Various applications use the crawler. For example, the CM indexing service uses the crawler when it builds indexes to enable search and classification operations. It uses the crawler to get references to all the resources in a directory which must be indexed. It passes the references on to a search engine which then accesses and analyses the corresponding resources to build an index. The subscription service also makes use of the crawler. It schedules the crawler to find out the contents of directories at regular intervals. It can then determine whether any objects in the directories have changed in the time between the scheduled crawls.
Note that a new crawler has been implemented in the package com.sapportals.wcm.service.xcrawler. The new implementation allows crawler to be resumed after a restart of the underlying SAP J2EE Engine. The previous implementation in package com.sapportals.wcm.service.crawler has been deprecated.
Further Information
See the package description com.sapportals.wcm.service.xcrawler for:
The Knowledge Management platform includes functionality to create and manage indexes. As indexes are the basis for a number of powerful features, index management plays a central role in the KM environment. Different types of indexes enable different types of operations. For example, a classification index enables the classification of documents and a search index enables the retrieval of information. The index management functionality can be used to build and administer search and classification indexes.
Further Information
If you want to use a 3rd party search engine, you can implement your own index service. The KM index management service consolidates all search results coming from different implementations of the index service and presents them to the end user. For more information, see the how-to guide:
Integrating 3rd Party Search Engines into KM Index Management
This enables applications to store and manage information about systems and the credentials required to log on to these systems. In the KM environment, a system is a server that needs to be accessed because data is stored there. For example, if resources are stored in a WebDAV, Lotus Notes and Exchange server then each of these is a system with certain attributes and each of these can have its own access policy that states requirements that have to be fulfilled before a user is granted access. In the following, these access requirements are referred to as credentials. It is the task of the system landscape service to store these credentials and information about the corresponding systems.
Credentials are defined and stored for a particular system type. They specify information that is required to permit access to a system type. Typically, access is restricted to persons who are correctly authenticated, that is persons whose user and password prove that they are allowed to access the system. However, these requirements can be extended to include further data like the specification of a start directory, the use of a particular access protocol or information about the logon mode. The system landscape service therefore enables the definition of individual access requirements that go beyond authentication with user and password.
Further Information
See Javadoc package description com.sapportals.wcm.service.landscape for:
The mime handler service provides information about mime types. Mime types are mapped to file extensions and associated with icons in the mimes.properties file. It is the task of the mime handler to read this information and to pass it on to applications whenever requested. Typically, applications need to know which mime type is associated with a particular resource, RID or file extension and which icon must be used to represent the mime type. For example, when an application presents a list of files to a user, it needs to know which icon must be displayed for each file type and can ask the mime handler to supply this information.
The mime handler is sometimes required to translate file endings into mime types. For example, when the Netscape browser is used, it only recognizes mime types and not file endings. For this reason, a file can only be opened with the Netscape browser if its extension has been translated into a mime type with the help of the mime handler service.
The notificator service offers applications and KM components a mechanism for sending notifications to recipients via email or SMS. In addition it provides support for compiling the contents and layout of notifications.
Further Information
The publishing pipeline is the technical infrastructure that enables the transformation of resources from one format to another or from one layout to another. When a filter has been defined for a particular file extension, mime type or folder, it is the pipeline that actually executes the transformation process specified by the filter.
Further Information
This service manages metadata for custom properties. The Knowledge Management environment distinguishes between two types of properties that can be assigned to resources:
When custom properties are entered, errors and inconsistencies can easily occur. For this reason, the property configuration service offers a way of predefining these properties and storing metadata about them that can be used to regulate the use and input of properties. The service allows applications to define characteristics and value ranges for properties which are valid for all repositories. This definition can then be used by an application to ensure that property data is always entered consistently and correctly.
The metadata for predefined properties helps to control user input. For example, an application can use the metadata to display the names and value ranges which are predefined for properties on the user interface. When a user enters a value for a property, he simply selects the property and one of the values offered. As a result, property data is entered correctly and can subsequently be used as a reliable basis for other operations like a property search.
You can group together predefined properties in an ordered fashion using the property structure service. Properties can be assigned to groups and these can, in turn, be assigned to structures. Groups can be nested so that every structure and group can contain properties and groups.
Property groups and structures are used to render properties in a predefined order.
The relation service is used to manage and store relations between
resources and other objects.
Examples of relations are, for example, resource X is an appendix of
document B or resource x belongs to task Y.
The scheduler is a service that manages the execution of tasks for applications. An application can register a task with the scheduler and specify a time when it must be executed. The scheduler then ensures that the task is started at the right time and monitors its execution.
The service is particularly useful for tasks that have to be performed regularly. For example, the subscription service uses the scheduler to ensure that directories containing relevant documents are crawled at regular intervals.
Further Information
See the Javadoc package description com.sapportals.wcm.service.scheduler for:
The task queue service allows components to place tasks in a task queue. Other components, which are responsible for processing these tasks, carry them out.
The service is mainly intended for a cluster environment where several instances of Content Management run on different machines. The task queue is located on a single machine, but with the help of the scheduler service, the tasks are executed by components on different machines. The scheduler directs the tasks to a specific CM instance for execution and thus enables the distribution of the system load.
Further Information
See the Javadoc package description com.sapportals.wcm.service.scheduler for technical details.
In the KM environment, resources are identified and accessed on the basis of their URI (RID). However, in certain circumstances, the URI alone is not sufficient to uniquely identify a resource. For example if a resource is moved or renamed then its URI changes. An application that has stored the original URI may no longer be able to identify and access the resource. For this reason, the KM Platform provides a URI Mapper service that maps a URI to a unique ID. This ID does not change even if the resource is moved or renamed and can always be used by applications to uniquely identify a resource.
Services, controls and repositories access resources through their URLs. The IURLGeneratorSErvice interface offers methods to create URLs for resources and to build valid URLs from partial information known to calling objects. The service uses information from the configuration of the running Content Management system to create complete URLs that point to web pages and can, for example, be included in pages or emails.
Further Information
See the Javadoc package description com.sapportals.wcm.service. urlgenerator for: