What is SpeakRight?

SpeakRight is an open-source Java framework for writing speech recognition applications in VoiceXML.Unlike most proprietary speech-app tools, SpeakRight is code-based. Applications are written in Java using SpeakRight's extensible classes. Java IDEs such as Eclipse provide great debugging, fast Java-aware editing, and refactoring. Dynamic generation of VoiceXML is done using the popular StringTemplate templating framework. Read more...

See Getting Started, Tutorial, and Table of Contents

Thursday, June 14, 2007

Initialization

SpeakRight apps normally run in three different environments: in a JUnit test, in the interactive tester, and most importantly in a servlet. You can avoid problems by creating a single piece of initialization code that is used across all environments. This pace is called the app factory. It should be derived from SRFactory, which performs standard initialization.

Your class should override onCreateRunner and onInitRunner to do additional initialization, such as:
  • create and attach a model object
  • register prompt file(s)
  • set the extension point factory
  • other things. For example, the SimpsonsDemo app records votes in a text file, and its Voting object needs to be initialized with the path
Initialization is done using the createRunner method of SRFactory

public SRRunner createRunner(String projectDir, String returnUrl, String baseUrl, ISRServlet servlet);

The projectDir is a path to the application's base directory, which usually has sub-directories audio, grammar, and sro.

The two URLs are only needed in a servlet environment. returnUrl is the URL that the VoiceXML page should postback to. baseUrl is used to generate URLs for audio and grammars.

servlet can be null. It's an extension point that allows the servlet to do extra initialization.

Now let's look at each environment in turn.

JUnit

In a unit test, the dependencies can be visualized like this, from top to bottom:

JUnit test class
App (your callflow)
SRRunner
SRFactory or your derived class
SRConfig

Use your app factory to create a runner
AppFactory factory = new AppFactory();
SRRunner run = factory.createRunner();
Then run your application using the start and proceed methods of SRRunner.

If your app uses properties in the srf.properties file, you need to initialize SRConfig first. JUnit 4 has a per-class initializer called @BeforeClass

@BeforeClass static public void redirectStderr() {
SRConfig.init("C:\\source\\app2\\", "srf.properties");
}


Interactive tester

The interactive tester is a console app. It's The dependencies can be visualized like this, from top to bottom:

App (your callflow)
SRInteractiveTester
SRRunner
SRFactory or your derived class
SRConfig

SRInteractiveTester inits SRConfig for you.

SRInteractiveTester tester = new SRInteractiveTester();

AppFactory factory = new AppFactory();
SRRunner runner = factory.createRunner(appDir, "http://def.com", "", null);

App app = new App();
tester.init(app, run);
tester.run();

Servlet

In a servlet, the dependencies can be visualized like this, from top to bottom:

Servlet
App (your callflow)
SRRunner
SRServletRunner
SRFactory or your derived class
SRConfig

In a servlet the SRServletRunner class is used. You pass your app factory and it does initialization, including SRConfig. The SRRunner's project directory is set to the directory corresponding to the web apps' "/" url.

The code in doGet should be
SRServletRunner runner = new SRServletRunner(new AppFactory(), null, request, response, "GET");

if (runner.isNewSession()) {
SRRunner run = runner.createNewSRRunner(this);

IFlow flow = new App();
runner.startApp(flow);
}
else {
runner.continueApp();
}

The code in doPost should be
SRServletRunner runner = new SRServletRunner(new AppFactory(), null, request, response, "POST");

if (runner.isNewSession()) {
//err!!
runner.log("can't get new session in a POST!!");
}
else {
runner.continueApp();
}


SRConfig

SRConfig provides access to an srf.properties file. Properties are often used by the constructors of flow objects. Therefore it's important to initialize SRConfig early:

SRConfig.init(path, "srf.properties");

For console apps or JUnit, a hard-coded path is used. For servlets, this is done for you by SRServletRunner, which uses the directory corresponding to the web app's "/" base url.

Currently the SpeakRight framework itself does not use any properties, but applications are free to.

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