OSGi blabber sample application

The blabber sample application is a microblogging application, used to enable many different people to share brief comments. This sample application shows how to write and package bundles into an enterprise bundle archive (EBA) file. The sample includes example code for Blueprint management, bean injection, using and publishing services from and to the OSGi service registry, and the use of Java™ persistence.

Before you begin

The sample application requires that the supplied com.ibm.samples.websphere.osgi.logging.api.jar and com.ibm.samples.websphere.osgi.logging.impl.jar bundles are installed into the internal bundle repository. The following procedure describes how to do this. These two JAR files, and the blabber sample EBA file, are provided in the installableApps directory of the OSGi_blabberSample.zip compressed archive file.

About this task

The blabber sample application consists of two bundles, divided into the following functional areas:

com.ibm.samples.websphere.osgi.blabber.persistence, which contains code relating to the Java Persistence API (JPA) layer, and also contains the interface that is used by the main application code.
com.ibm.samples.websphere.osgi.blabber, which contains the main application logic code, and interacts between the web front end and the back end persistence code layer.

You can use scripts to completely install the sample application, or you can use scripts to complete the initial configuration of the application then use the administrative console to install the application into the application server. You can also use, modify and remove the sample.

Procedure

Configure and install the blabber sample.

You can either configure and install the sample using scripts (the first optional step in the instructions that follow), or you can configure the sample using scripts then install the sample using the administrative console (the second optional step in the instructions that follow).

The scripts that you use to do this are provided in the scripts directory of the OSGi_blabberSample.zip compressed archive file. The createblabberDb.sql script contains the necessary configuration commands to create the required Derby database and associated tables. The blabberSampleInstall.py script contains the required jython to create data sources, and to install the blabber sample with default configuration. You should fully qualify the path to the script if you do not run it from the directory that contains the script.

Note: If you have data sources already defined in your environment, and these data sources have the same name as the data sources that are specified in the blabberSampleInstall.py script, then the sample might not install and run successfully.

In the following steps you must substitute your own values for the variables app_server_root, profileName, serverName, nodeName, blabberSample.eba_Location, com.ibm.samples.websphere.osgi.logging.api.jar_Location, com.ibm.samples.websphere.osgi.logging.impl.jar_Location, uncompressed_sample_directory, and path_to_ant.

Optional: Configure and install the sample using scripts.

Create and configure the BLABBERDB Derby database and associated tables by running the following command.
On UNIX platforms:
```
app_server_root/derby/bin/embedded/ij.sh scripts/createBlabberDb.sql
```
On Windows platforms:
```
app_server_root\derby\bin\embedded\ij.bat scripts\createBlabberDb.sql
```

Create the data sources, create the business-level application and import the .eba file as an asset by running the following command.

Note: The target application server must be running before you use this script.

On UNIX platforms:

app_server_root/profiles/profileName/bin/wsadmin.sh 
     -f scripts/blabberSampleInstall.py fullInstall serverName nodeName 
     blabberSample.eba_Location 
     com.ibm.samples.websphere.osgi.logging.api.jar_Location
     com.ibm.samples.websphere.osgi.logging.impl.jar_Location

On Windows platforms:

app_server_root\profiles\profileName\bin\wsadmin.bat 
     -f scripts\blabberSampleInstall.py fullInstall serverName nodeName 
     blabberSample.eba_Location 
     com.ibm.samples.websphere.osgi.logging.api.jar_Location
     com.ibm.samples.websphere.osgi.logging.impl.jar_Location

Optional: Configure the sample using scripts, then install the sample using the administrative console.
1. Create and configure the "BLABBERDB" Derby database and associated tables by running the following command.
  On UNIX platforms:
```
app_server_root/derby/bin/embedded/ij.sh scripts/createBlabberDb.sql
```
  On Windows platforms:
```
app_server_root\derby\bin\embedded\ij.bat scripts\createBlabberDb.sql
```
2. Create the data sources by running the following command.
  On UNIX platforms:
```
app_server_root/profiles/profileName/bin/wsadmin.sh 
     -f scripts/blabberSampleInstall.py setupOnly serverName nodeName
```
  On Windows platforms:
```
app_server_root\profiles\profileName\bin\wsadmin.bat 
     -f scripts\blabberSampleInstall.py setupOnly serverName nodeName 
```
3. Use the administrative console to add the com.ibm.samples.websphere.osgi.logging.api.jar file to the internal bundle repository.
  1. Navigate to Environment > OSGi bundle repositories > Internal bundle repository
  2. Click New.
  3. Select the file system that hosts the com.ibm.samples.websphere.osgi.logging.api.jar file, then click Browse.
  4. Browse to the uncompressed_sample_dir/installableApps directory.
  5. Select the com.ibm.samples.websphere.osgi.logging.api.jar file, then click OK.
  6. Click OK.
  7. Click Save.
4. Repeat the previous step to add the com.ibm.samples.websphere.osgi.logging.impl.jar file to the internal bundle repository.
5. Use the administrative console to import the application (EBA file) as an asset, and to configure the business-level application.
  1. Import the asset.
    1. Navigate to Applications > New application > New Asset.
    2. On the Upload asset panel, browse to the uncompressed_sample_dir/installableApps directory.
    3. Select the com.ibm.samples.websphere.osgi.blabber.app.eba file, then click Next.
    4. On the Select options for importing an asset panel, click Next.
    5. On the Summary panel, click Finish.
    6. Click Save.
  2. Create the business-level application and add the asset.
    1. Navigate to Applications > New application > New Business Level Application.
    2. On the New Application panel, enter a name for the business-level application. For example, blabber.
    3. Click Apply.
    4. In the Deployed assets pane, click Add > Add Asset.
    5. Select the com.ibm.samples.websphere.osgi.blabber.app.eba asset, then click Continue.
    6. On the Set options panel, click Next.
    7. Select a target for the composition unit, then click Next.
    8. Modify the context root if required, then click Next.
    9. Modify the virtual host if required, then click Next.
    10. On the Summary panel, click Finish.
    11. Click Save.
6. Start the application.
  1. Select the newly-created business-level application.
  2. Click Start.

Use the blabber sample.

Use your browser to navigate to http://server:port/context_root/ (by default http://localhost:9080/blabber/).
The main blabber screen is displayed.
Register yourself as a user.
You need to do this before you can create blabber entries.
1. Click Click here to sign-up!.
2. Complete the form.
3. Click Create my account!.
The status update home page is displayed.
Explore the blabber application.
From the status update home page, you can select any of the following options:
- Set a status message.
- Search for and track other users.
- View your profile.
- Sign out.
Within each of the previous options, there is an option to return to the status update home page.
Note:
- When you enter some status then click Update, your status message is displayed on the current page.
- You can only view or use the tracking option if the application has more than one user.

Modify the blabber sample.

All the source code for this application is provided in sub-directories the uncompressed_sample_dir directory. Each part of the project has its own ant build.xml script. To build the whole application into a newly-available EBA file, you use the ant build.xml file located in the uncompressed_sample_dir directory. WebSphere® Application Server ships a version of ant in its bin directory called ws_ant. To build the sample, you also need several JAR files on the ant classpath. To simplify matters, you can edit the was.root property in the supplied build.properties file to point to these JAR files.

Put the following jar files on the ant classpath:
- javax.j2ee.persistence.jar
- javax.j2ee.jsp.jar
- javax.j2ee.servlet.jar
- com.ibm.ws.prereq.jaxrs.jar
These JAR files are available in the plugins directory of Websphere Application Server. Edit the was.root property in the supplied uncompressed_sample_dir/scripts/build.properties file, and point it to your app_server_root directory. If you have copied the jars to another location, modify the was.root property to point to this location.
Run the following ant command from the uncompressed_sample_dir directory:
```
path_to_ant -propertyfile scripts/build.properties -buildfile build.xml
```
The newly-built binary file (EBA file) is in the uncompressed_sample_dir/output directory.
Note: This is the only location to which this EBA file is written. The script does not overwrite the original binary file located in the uncompressed_sample_dir/installableApps directory.

Remove the blabber sample.

To remove the blabber sample, you complete the following 3 steps:

Remove the application configuration and the data sources, either by using a script (the first optional step in the instructions that follow), or by using the administrative console (the second optional step in the instructions that follow).
Remove the shared logging bundles from the internal bundle repository.
Remove the database.

Note: Only remove the bundles if you have no other applications installed that use them. Both the blabber and blog sample applications use the shared logging bundles, so if both applications are installed these bundles should not be removed.

The uninstall script is provided in the scripts directory of the OSGi_blabberSample.zip compressed archive file. The blabberSampleUninstall.py script contains the required jython to remove data sources and to remove the installation of the blabber sample with default configuration. You should fully qualify the path to the script if you do not run it from the directory that contains the script.

In the following steps you must substitute your own values for the variables app_server_root, and profileName.

Optional: Remove the application configuration and the data sources by running the following command.
Note: The target application server must be running before you use this script.
On UNIX platforms:
```
app_server_root/profiles/profileName/bin/wsadmin.sh 
          -f scripts/blabberSampleUninstall.py
```
On Windows platforms:
```
app_server_root\profiles\profileName\bin\wsadmin.bat 
          -f scripts\blabberSampleUninstall.py
```
Optional: Remove the application configuration and the data sources by using the administrative console.
1. Remove the application configuration.
  1. Navigate to Applications > Application types > Business-level applications.
  2. Select the business-level application representing the blabber sample application, then click Stop.
  3. Click the business-level application representing the blabber sample application to view the configuration details.
  4. Select all the deployed assets, then click Delete.
  5. Click OK to confirm removal.
  6. Click Save.
  7. Select the business-level application representing the blabber sample application, then click Delete.
  8. Navigate to Applications > Application types > Assets.
  9. Select the com.ibm.samples.websphere.osgi.blabber.app.eba asset, then click Delete.
  10. Click OK to confirm removal.
  11. Click Save.
2. Remove the data sources.
  1. Navigate to Resources > JDBC > Data sources.
  2. Select the two data sources configured for the blabber application.
  3. Click Delete.
  4. Click Save.
Remove the shared logging bundles from the internal bundle repository by using the administrative console.
1. Navigate to Environment > OSGi bundle repositories > Internal bundle repository.
2. Select the following bundles:
  - com.ibm.samples.websphere.osgi.logging.api.jar
  - com.ibm.samples.websphere.osgi.logging.impl.jar
3. Click Delete.
4. Click Save.
Remove the database.
On UNIX platforms, open a command prompt, then enter the following command:
```
cd app_server_root/derby
rm -fr BLABBERDB
```
On Windows platforms, delete the app_server_root\derby\BLABBERDB directory.

Results

The following illustration shows the correctly running sample:

A screen capture of the blabber application Home page. The page title is "Generic Status Update Application", underneath which are two vertical panes: One pane provides the option to register a new user by pressing a button labeled "Click here to sign up!", and the other pane enables existing users to sign in by entering a user name and password, then clicking a button labeled "Sign in!".