Liberty Profile

Introduction to Liberty Profile:

• The Liberty profile provides a simplified stand-alone run time for web applications, supporting a subset of the programming model and run time features available with the full profile. Any application that runs on the Liberty profile will also run on the full profile.
• It is a good option for developers who are building web applications that do not require the full Java EE environment of traditional enterprise application server profiles. For production environments, enterprise qualities of service, such as security and transaction integrity, are enabled as required.
• Liberty profile instances are stand-alone servers similar to application server profiles;however, they are characterized by a dynamic runtime based on the OSGi model. This design allows you to configure the server runtime stack and features in real time. This design also results in a small server footprint and fast startup time because the server uses only feature that are needed by the applications. For example, if an application requires just a servlet engine, Liberty profile can be configured to only start the WebSphere Application Server kernel, an HTTP endpoint for connection, and a web container. If the application needs additional features, such as database connectivity, the Liberty profile configuration can be dynamically modified to include the JDBC feature without the need of a server restart.
• The Liberty profile includes the following key features:

• • A dynamic and flexible run time to load only what the application needs
  • A quick startup time (under 5 seconds with simple web applications)
  • A simplified configuration that uses a single configuration file or modular configuration
  • Support for deploying applications developed in the Liberty profile to run in the full profile
  • Support of web applications, OSGi applications, and Java Persistence API
  • (New in V8.5.5) Support for web services
  • (New in V8.5.5) Support for Java Messaging Support (JMS)
  • A secure server environment. User registry options include single or (New in V8.5.5) federated LDAP registries, role based authorization, SSL, single sign-on, custom login modules, (New in V8.5.5) OAuth support, and more.
  • (New in V8.5.5) Support for the use of MongoDB, a NoSQL database system. The server and client drivers are not shipped with WebSphere Application Server.
  • Ability to deploy an application and configured server as a package
  • (New in V8.5.5) Ability to extend the Liberty profile with custom features
  • (New in V8.5.5) Ability to cluster servers for high availability and scalability
  • (New in V8.5.5) Centralized operational management of groups of Liberty servers and of Liberty clusters.
  • Managed, centralized deployment for many nodes of a packaged application and server using the Job Manager.
  • Availability of WebSphere Application Server Developer Tools as Eclipse plug-ins for broad tool support
  • Support for z/OS platform native features such as System Authorization Facility (SAF),
  • Resource Recovery Services (RRS), and z/OS Workload Manager (WLM)
• The Liberty profile comprises the Liberty profile kernel and any number of optional features that run inside of a single Java Virtual Machine (JVM) process. Most of the kernel runs as OSGi bundles within an OSGi framework. The Liberty profile requires Java Runtime Environment version 6 or higher.
• When the server is started, the launcher bootstraps the kernel and starts the OSGi framework. The server configuration is parsed, and features are loaded by the feature manager. The kernel makes extensive use of OSGi services to provide a highly-dynamic runtime:
• System configuration is managed by the OSGi configuration admin service.
• The OSGi declarative services component is used to manage the lifecycle of system services.
• Application and configuration file changes are detected by the file monitor service. The file monitor service detects changes that are then reflected in real-time updates.

Configuration: 

1) You can obtain the latest Liberty profile package from the following WASdev community website:

click on WASDevCommunity

2) Configuring JRE

• The Liberty profile requires a Java Runtime Environment to run in. By default, it does not share the Java Runtime Environment with the WebSphere Application Server, so you must specify the JRE location. The JVM on the system PATH is used by default.

The Liberty profile runtime searches for the java command in the following order of properties:

• JAVA_HOME, JRE_HOME and PATH.
• Additionally, you can use the Liberty profile server.env configuration file to set up a specified Java Runtime. To configure the Java runtime using this file, add the following line into the file:
• JAVA_HOME=C:\IBM\jre6
• If the file does not exist, you must create it manually in the Liberty profile etc directory.
  
• Installing the Liberty profile is as simple as running a self-extracting archive. The WASdev web site provides three archives for V8.5.5:
• Liberty profile: wlp-developers-runtime-8.5.5.0.jar - This archive contains the Liberty core features (equivalent to the V8.5.0 Liberty profile) plus the features that complete the web profile support.
• Extended content for Liberty profile: java -jar wlp-developers-extended-8.5.5.0.jar - This archive includes web services, messaging, and MongoDB support. 
• Embeddable EJB container: java -jar wlp-developers-extras-8.5.5.0.jar - This archive includes the embeddable EJB container and JPA client.
• To manually install a Liberty profile archive:
• java -jar wlp-developers-runtime-8.5.5.0.jar
• Press x to skip reading the license terms, or press Enter to view them.
• Press Enter to view the license agreement.
• Press 1 if you agree to the license terms and want to proceed.
• Provide the installation path for the Liberty profile, for example C:\IBM\WebSphere, and press Enter.
• Server:
• Run following Command to create the server: server create server1
• Run following Command to start the server: server run server1
• Starts the server in debug mode: server debug server1
• Stop: server stop server1
• Status: server status server1
• Configuration:

• server description should include Server Name
• feature - what feature we need to enable
• host - hostname on which the JVM is installed
• port - WC Default Host and WC Default Host Secure
• Application ID - Name of the WAR
• location - Full path of war file
• name - Name of the WAR 
• type - WAR
• if we need to add Data Source Config: We can use include statement as demonstrated below:
  
  
  
  
  
  
• The bootstrap.properties file is the second file that can be used for the Liberty profile server configuration. Changes to this file require the server to be restarted. By default this file is not generated when you create the Liberty profile server instance. If you want to use this file, you first have to create it. Place this file in the main server directory along side the server.xml file. The bootstrap properties are generally used to initialize the runtime environment for a particular server.
• Data Source Configuration:

• Parameters:

  Attribute name	How the configuration update is applied
  beginTranForResultSetScrollingAPIs	The update is effective immediately.
  beginTranForVendorAPIs	The update is effective immediately.
  commitOrRollbackOnCleanup	The update is effective immediately.
  connectionManagerRef	All connections and the connection pool are destroyed. The data source is then managed by the new connection manager
  connectionSharing	The update is applied with each first connection handle in a transaction.
  isolationLevel	The update is applied with new connection requests. Current connections retain their isolation level
  jdbcDriverRef	All connections and the connection pool are destroyed. The new JDBC driver is then used.
  jndiName	All connections and the connection pool are destroyed. The new JNDI name is then used.
  propertiesRef	If the data source is Derby Embedded, all connections and the connection pool are destroyed before new properties go into effect. For other JDBC drivers, the new properties go into effect with new connection requests.
  queryTimeout	The update is effective immediately.
  statementCacheSize	The statement cache is resized upon next use.
  supplementalJDBCTrace	All connections and the connection pool are destroyed. The new setting is then used.
  syncQueryTimeoutWithTransactionTimeout	The update is effective immediately.
  transactional	The update is applied to new connections and existing connections not in use from the connection pool.
  type	All connections and the connection pool are destroyed. The new setting is then used.
  agedTimeout	The update is effective immediately.
  connectionTimeout	The update is effective immediately.
  maxIdleTime	The update is effective immediately.
  maxNumberOfMCsAllowableInThread	The update is effective immediately.
  maxPoolSize	The update is effective immediately.
  minPoolSize	The update is effective immediately.
  numConnectionsPerThreadLocal	The update is effective immediately.
  reapTime	The update is effective immediately.
  purgePolicy	The update is effective immediately.
  numConnectionsPerThreadLocal	The update is effective immediately.

• Integrating Messaging Queues

• The wasJmsServer-1.0 feature configures the Liberty server to support the JMS server run time that provides the capabilities for connections, transactions, persistence, security, and so on.
• The wasJmsClient-1.1 configures the Liberty server to support JMS client connectivity. This feature provides the resource adapter support that allows JMS clients to perform synchronous and asynchronous messaging activities.
• The Liberty profile server also supports the use of message-driven beans (MDB). The jmsMdb-3.1 feature provides support for deploying and configuring the JMS resources that are required for the MDB to run within the Liberty profile. This feature enables MDB to interact with either the embedded Liberty messaging or WebSphere MQ.
• If you want to perform a JNDI lookup for JMS resources, then you must also add the jndi-1.0 feature.
• Enable JMS in Binding Mode: 
  <wmqJmsClient nativeLibraryPath="/opt/mqm/java/lib64"/>

Implementing Security (LDAP)

• The Liberty profile provides support for securing the server runtime environment and web applications by using user registries, authentication, and authorization. For secure communication between the client and the server, you can enable SSL for the Liberty profile. A minimal or detailed configuration can be done by adding the ssl-1.0 server feature to the server configuration file.
• Implementing LDAP: