Extension Point Deployment Sample

This sample is a variation on the Extension Point Operator sample. For maximum benefit, first run and understand the Extension Point sample before working through this variation.

The purpose of this variation is to illustrate the use of StreamBase deployment files to define the modules to be run by an Extension Point operator. The StreamBase interface in this sample specifies externally defined modules. Two example .sbdeploy deployment files are provided, which you use to run this sample.

Note

Do not run this sample's EventFlow file, ExtPtDeployment.sbapp. Instead, run one or both of this sample's StreamBase deployment files as described in the steps below.

This sample uses an Extension Point operator to dispatch tuples to two pairs of sub-modules, based on a user-specified action at runtime. The first pair of sub-modules either doubles or triples the integer field in the incoming tuple, depending on the specification in the action field of the incoming tuple. If the action field is null, the incoming tuple is sent to both sub-modules. You run ExtPtDeployment1.sbdeploy to run this sample with the first pair of sub-modules.

The second pair of sub-modules have the same relationship to the top-level module, but they triple or quadruple the incoming tuple's integer field (instead of double or triple). Run ExtPtDeployment2.sbdeploy to run this sample with the second pair of sub-modules.

This sample illustrates several aspects of Extension Point operators and StreamBase interfaces. There are two related samples that complete the picture on these subjects:

Sample Description
Interfaces Sample Demonstrates how to use StreamBase interfaces to enforce a set of stream and schema definitions, and to use different implementations of the same interface for different purposes.
Extension Point Operator Sample This sample uses an Extension Point operator to dispatch tuples based on a user-specified action to one of two modules, which double or triple an integer field within the tuple. If no action is specified, the tuple is sent to both modules. This sample illustrates StreamBase interfaces used with the Extension Point operator, and illustrates module dispatch based on a predicate condition.

This Sample's Files

The Extension Point Deployment sample is composed of following files:

File Purpose
ExtPtDeployment.sbapp The top-level application for this sample. To run this sample, DO NOT RUN this EventFlow module. Instead, run one of the two StreamBase deployment files described next.
ExtPtDeployment1.sbdeploy A StreamBase deployment file that specifies running either Doubler.sbapp or Tripler.sbapp as modules that implement the Multiplier interface.
ExtPtDeployment2.sbdeploy A StreamBase deployment file that specifies running either Tripler.sbapp or Quadrupler.sbapp as modules that implement the Multiplier interface.
The following files are located in the Modules subdirectory of the operator project directory.
Multiplier.sbint A StreamBase interface that defines two input streams and one output stream, and defines named schemas used by those streams.
Doubler.sbapp A module that implements the streams and schemas defined in the Multiplier.sbint interface. This module doubles its input value, and appends as a list(string) the StreamBase path through this module.
Tripler.sbapp Another module that implements the Multiplier.sbint interface. This module performs the same actions as Doubler.sbapp except that it triples its input value.
Quadrupler.sbapp Yet another implementation of the Multiplier.sbint interface. This module quadruples its input value.

Open ExtPtDeployment.sbapp in Studio and look at the Properties view for the Extension Point operator named Multiply. The Concurrency tab is entirely responsible for directing input tuples to one or both of the referenced modules.

  • If a tuple enters input port 2, the dispatch style is Broadcast, which means the tuple is sent to both modules.

  • If a tuple enters input port 1, the dispatch style is Name. In this case, the expression lower(action) must resolve to the identifier of one of the modules defined in the StreamBase deployment file.

Unlike the Extension Point sample, the ExtPtDeployment.sbapp module specifies Defined: Externally in the Modules tab of the Multiply interface's Properties view, and defines an Extension Point ID of extpt.deployment.multiplier. The Extension Point ID is what links the EventFlow module to one or more StreamBase deployment files. To be able run this EventFlow application, a deployment file must specify:

  • This EventFlow module's name in the module attribute of the <application> element.

  • The same Extension Point ID in the target-id attribute of an <extension-point> element as specified in the EventFlow module.

The following fragment of this sample's deployment files shows the required lines:

...
<runtime>
  <application container="default" module="ExtPtDeployment.sbapp">
    <extension-point-contents>
      <extension-point target-id="extpt.deployment.multiplier">
...

Running This Sample in StreamBase Studio

  1. In the Package Explorer, open the sample_operator project folder.

  2. Double-click to open the ExtPtDeploymnent1.sbdeploy deployment file. Make sure the Deployment File Editor is the currently active tab in Studio.

  3. Click the Run button. This opens the SB Test/Debug perspective and starts the application module named in the deployment file.

  4. In the Application Output view, select the Output output stream. No output is displayed at this point.

  5. In the Manual Input view, select the Input input stream.

  6. Enter the following field values:

    Field Enter this value
    value 2
    action double
  7. Click Send Data, and a tuple arrives in the Application Output view. Select the new tuple and observe this data below the output stream table:

    value=2, action=double, newValue=4, path=[Entering port 1 for Name dispatch,Doubler.sbapp]
  8. In the Manual Input view, enter the following field values:

    Field Enter this value
    value 2
    action triple
  9. Click Send Data, and a tuple arrives in the Application Output view. Select the new tuple and observe this data below the output stream table:

    value=2, action=triple, newValue=6, path=[Entering port 1 for Name dispatch,Tripler.sbapp]
  10. In the Manual Input view, enter the following field values:

    Field Enter this value
    value 3
    action null
  11. Click Send Data, and two tuples arrive in the Application Output view. Select the new tuples and observe this data below the output stream table:

    value=3, action=null, newValue=6, path=[Entering port 2 for Broadcast dispatch,Doubler.sbapp]
    value=3, action=null, newValue=9, path=[Entering port 2 for Broadcast dispatch,Tripler.sbapp]
  12. Press F9 or click the Stop Running Application button to stop the first deployment application.

  13. Double-click to open the ExtPtDeploymnent2.sbdeploy deployment file, and make sure the Deployment File Editor is the currently active tab in Studio.

  14. Click the Run button to run this second deployment file. As before, this opens the SB Test/Debug perspective and starts the application.

  15. Enter input tuples in the Manual Input view using steps similar to steps 6 through 11, but this time use action values triple, quadruple, and null. Compare the results with running the first deployment file.

  16. When done, press F9 or click the Stop Running Application button to stop the second deployment application.

Running This Sample in Terminal Windows

This section describes how to run the sample in UNIX terminal windows or Windows command prompt windows. On Windows, be sure to use the StreamBase Command Prompt from the Start menu as described in the Test/Debug Guide, not the default command prompt.

  1. Open three terminal windows on UNIX, or three StreamBase Command Prompts on Windows. In each window, navigate to your workspace copy of the sample, as described above.

  2. In window 1, start StreamBase Server running the first deployment file. You must specify the provided server configuration file so that the application can locate the provided interface and module files in the Modules folder. Enter:

    sbd -f op-samples.sbconf ExtPtDeployment1.sbdeploy
  3. In window 2, type:

    sbc deq Output

    No output is displayed at this point, but the dequeuer is prepared to receive output.

  4. In window 3, type:

    sbc enq Input

    The sbc command in window 3 now waits for keyboard input. Type:

    2, double
    2, triple
    3, null

    Look for output lines like the following in window 2:

    2,double,4,"[Entering port 1 for Name dispatch,Doubler.sbapp]"
    2,triple,6,"[Entering port 1 for Name dispatch,Tripler.sbapp]"
    3,null,6,"[Entering port 2 for Broadcast dispatch,Doubler.sbapp]"
    3,null,9,"[Entering port 2 for Broadcast dispatch,Tripler.sbapp]"
  5. In window 3, type: Ctrl+C to exit the sbc session.

  6. In window 3, type the following command to terminate the server and dequeuer: sbadmin shutdown

  7. Now, in window 1, run the second deployment file:

    sbd -f op-samples.sbconf ExtPtDeployment2.sbdeploy
  8. In window 2, type:

    sbc deq Output

    No output is displayed at this point, but the dequeuer is prepared to receive output. This window will eventually show the output of the application.

  9. In window 3, type:

    sbc enq Input

    The sbc command in window 3 now waits for keyboard input. Type:

    2, triple
    2, quadruple
    3, null

    Look for output lines like the following in window 2:

    2,triple,6,"[Entering port 1 for Name dispatch,Tripler.sbapp]"
    2,quadruple,8,"[Entering port 1 for Name dispatch,Quadrupler.sbapp]"
    3,null,9,"[Entering port 2 for Broadcast dispatch,Tripler.sbapp]"
    3,null,12,"[Entering port 2 for Broadcast dispatch,Quadrupler.sbapp]"
  10. In window 3, type: Ctrl+C to exit the sbc session.

  11. In window 3, type the following command to terminate the server and dequeuer: sbadmin shutdown

Importing This Sample into StreamBase Studio

In StreamBase Studio, import this sample with the following steps:

  • From the top menu, select FileLoad StreamBase Sample.

  • Select operator from the Data Constructs and Operators category.

  • Click OK.

StreamBase Studio creates a single project for the operator samples.

Sample Location

When you load the sample into StreamBase Studio, Studio copies the sample project's files to your Studio workspace, which is normally part of your home directory, with full access rights.

Important

Load this sample in StreamBase Studio, and thereafter use the Studio workspace copy of the sample to run and test it, even when running from the command prompt.

Using the workspace copy of the sample avoids permission problems. The default workspace location for this sample is:

studio-workspace/sample_operator

See Default Installation Directories for the location of studio-workspace on your system.

In the default TIBCO StreamBase installation, this sample's files are initially installed in:

streambase-install-dir/sample/operator

See Default Installation Directories for the default location of studio-workspace on your system.