4.1.1. What is the Model Designer Tomcat Server ?

The Model Designer Tomcat server (hereafter called MDServer), is responsible for executing services invoked by the Model Designer client. Two types of services are handled by MDServer: query execution (i.e. execution of an SVG- based model against a sequence database), and database upload (i.e. a client sends to the server a new database).

The entire MDServer is written using a particular Java technology known as Servlet. This technology enables the creation of distributed application using the state of the art Web protocol: HTTP. Since MDServer itself is just a Servlet application that has to work in association with an HTTP server, it requires a Servlet engine. The standard Java Virtual Machine is used to execute a Java application on a desktop, so it is for Servlet: a Java Application Server is required to execute a Servlet-based application. To run the MDServer, we use Tomcat, the Servlet engine freely provided by the Apache Software Foundation.

4.1.2. How the server is organized ?

The Model Designer server has the following directory structure:

<ServerHomeDir>
     |
     |- databases
     |- prolog
     |- tmp
     |- tomcat

Directory ServerHomeDir is the location of the Model Designer Server application. As explained in the next section, that directory should refer to /local/mdesigner_devel.

Directory databases contains some databases that can be used to test the whole client/server system. It is the content of this directory that is used to create the list of available databases sent to the client when a user start a query submission to the server.

Directory prolog contains the Prolog programs that form the search engine of Model Designer Server application. This directory also contains the Unix shell script allowing to start the Prolog servers.

Directory tmp contains queries and databases sent by the client to the server.

Directory tomcat contains the ready-to-run Tomcat server along with the compiled Model Designer servlets.

4.1.3. Deploying the Model Designer Tomcat Server

To install the Model Designer server (hereafter called MDServer), do the following:

You have now install in the /local directory of your computer the directory structure (along with some files) required by the ModelDesigner server. Chapter Working with Model Designer will explain how to deploy, start and stop the server itself (i.e., the set of servlets).

4.2.1. What is a module ?

Model Designer source code is distributed within three modules:

• appserver: the source code of MDServer,

• core: the source code of the core of Model Designer client/server application.

• gui: the source code of the Graphical User Interface of Model Designer client application.

To work on these modules, you have to get a copy from the CVS server. The following sections explain how to do so.

4.2.2. How a source code module is organized ?

Each Model Designer development module has a particular directory structure:

<Module>
     |
     |- conf
     |- jar
     |- lib
     |- scripts
     |- src

Directory conf contains configuration files needed by the module.

Directory doc contains the compiled Javadoc of the module.

Directory jar contains librairies needed to compile/run the module.

Directory lib contains compiled source files (.class).

Directory scripts contains Ant scripts to manage a module from the command-line.

Directory src contains the Java source files of the module (.java) along with some Javadoc source files (.html).

In addition to those directories, the appserver module also has a directory named logol containing some Prolog source files needed by the Model Designer server.

For each module, all but the doc and lib directories are stored in the CVS repository. Directories doc and lib are automatically created while working on a module. It is strictly forbidden to commit them in the CVS repository.

Each module comes with some Ant scripts that can be used to handle the development process of a module from the command-line. To be used, those scripts have to be copied from the scripts directory to the module directory.

4.2.3. How the documentation module is organized ?

The organization of the doc module is described in the README file located in the root directory of that module. This file is available as soon as you check out the doc module from CVS.

4.2.4. Getting a module from CVS

There are two non compatible ways to manage the development process of the Model Designer platform using CVS:

1. using the command-line CVS client application,

2. using Eclipse.

Depending on your choice, there is no way back: if you choose to work using CVS on the command-line, you CAN NOT use the CVS embedded in Eclipse at the same time.

Getting a Model Designer development module from the CVS repository means that you will have a complete copy of the development files in your home directory. For that purpose, you need to prepare the following directory structure:

/udd/$USER
        |
        -- ModelDesigner
                    |
                    -- devel
                          |
                          |- appserver
                          |- core
                          -- gui

Starting from your home directory, you thus have to create a directory that will be called the Model Designer development home directory. Here that directory is ModelDesigner (in this example, that directory is directly under your home dir, but you can put the Model Designer development home directory anywhere else). In that directory, you have to create the devel directory, and then there you create the module directories: appserver, core and gui. Note that if you are going to only work on a unique module, you just have to create the directory for that module.

The directory structure is now prepared to receive the Model Designer source code modules from the CVS repository.

If you plan to work on the ModelDesigner documentation (for example, if you plan to update this manual), you need to add a doc directory under the ModelDesigner one, as follows:

/udd/$USER
        |
        -- ModelDesigner
                    |
                    -- devel
                    |     |
                    |     ...
                    |
                    -- doc

5.1.1. Starting the GUI

The following section supposed that you checked the gui module out from the CVS repository. If it is not the case, please refer to the section Getting a module from CVS. There are two ways to start the Model Designer GUI: from the command-line and from Eclipse.

5.1.2. Model Designer Client directory structure

The first time the client application of Model Designer is started, a particular directory structure is created in your home directory:

/udd/$USER
        |
        -- .mdesigner_devel
               |
               |- conf
               |- databases
               |- models
               |- queries

Directory conf contains configuration files needed by the client.

Directory databases contains the list of databases uploaded by you (while using the client application) onto the Model Designer server.

Directory models contains examples of SVG-based models.

Directory queries contains the list of queries sent by you (while using the client application) to the Model Designer server.

Directory .mdesigner_devel itself contains log files created by the Model Designer client application during its execution. Those log files may be usefull to track bugs.

5.2.1. Starting MDServer

Here is the procedure to start MDServer from the command-line (this cannot be done from Eclipse):

You have to be aware that using the MDServer means that some network ports on your computer are opened to the IRISA internal network. There is no real security problems here, but keep in mind that ports 8090 (opened by Tomcat, i.e. the Java Application Server running MDServer) and 760X (opened by several Prolog servers running in parallel; X ranges from, and including, 0 to 9) are opened. Now, if you prefer to close those ports when not using Model Designer, you have to shut the server down.

5.2.2. Shutting down MDServer