Required Components

Applications described in this document require the following components:

The current version dependencies for each of the components above, can be found in the Dependencies document for the Metadata Service. Each of the above component JAR files must be referenced in the calling environment's class path. This can be accomplished either by specifying the references in the CLASSPATH environment variable or in the -classpath option of the java interpreter. The components may also be referenced by specifying the directory containing the component JAR files using the java.ext.dirs property.

Java Properties

This section details the Java properties utilized by the client applications of the Metadata Service.

Generic Properties

The following generic properties may be specified for the Metadata Service for all instances:

RMI Properties

The RMI protocol support properties must be specified for the Metadata Service for all instances.

Logging Properties

The logging capability properties specify how the messages generated by the application will be handled.

Miscellaneous Properties

The miscellaneous properties provide instance specific values.

CORBA Property Files

Two CORBA related property files are required to be accessible. They are the jacorb.properties and orb.properties file. They can also be named .jacorb.properties and .orb.properties respectively. These files should be present in either a directory specified in the class path, the home directory, the current directory or in the Java installation library directory ($JAVA_HOME/jre/lib).

OODT Configuration File

The OODT configuration file is required to be accessible. The file may be named edarc.xml or .edarc.xml . This file should be present in the home directory or in the Java installation library directory ($JAVA_HOME/jre/lib). This file may also be referenced by specifying the file name using the jpl.eda.Configuration.file property. The following is an example of a minimal configuration file for the client applications:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC
  "-//JPL//DTD EDA Configuration 1.0//EN"
  "http://oodt.jpl.nasa.gov/dtd/configuration.dtd">

<configuration>

  <webServer>
    <host>localhost</host>
    <port>80</port>
    <dir>/usr/local/metadata/htdocs</dir>
  </webServer>

  <nameServer>
    <iiop>
      <host>localhost</host>
      <port>2809</port>
    </iiop>
  </nameServer>

  <properties>
    <!-- Log listener properties. -->
    <key>jpl.eda.util.LogInit.listener</key>
    <value>jpl.eda.util.ScreenLogger</value>
    <key>jpl.eda.util.LogInit.categories</key>
    <value></value>

    <!-- Miscellaneous properties. -->
    <key>jpl.eda.metadata.registry.tmpDir</key>
    <value>/tmp</value>
  </properties>

</configuration>
        

In order for a client application to find the CORBA Name Server, the host and port elements inside the webServer element must be specified correctly. The nameServer element is only used when starting the Name Server. The log listener properties specified in the configuration file indicate that all messages generated by a client application will be sent to the terminal's standard error stream.

Add Event

This event enables a schema file to be submitted and registered in the Schema Registry with corresponding metadata. The additional command-line arguments are as follows:

The metadata file must be an XML document conforming to a specific structure. Although it is recommended that all of the Dublin Core elements be utilized when describing a schema file, only the DC.Identifier element is required. The following is an example of the metadata file:

<?xml version="1.0"?>
<dataDictionary>
  <metadata>
    <DC.Identifier>EDM.Test</DC.Identifier>
    <DC.Title>EDM Test Schema</DC.Title>
    <DC.Format>text/xml</DC.Format>
    <DC.Description>This is a test.</DC.Description>
    <DC.Creator>EDM</DC.Creator>
    <DC.Subject>EDM Test</DC.Subject>
    <DC.Publisher>Jet Propulsion Laboratory</DC.Publisher>
    <DC.Contributor>Cynthia Wong</DC.Contributor>
    <DC.Date>2004-09-29</DC.Date>
    <DC.Type>XSD</DC.Type>
    <DC.Source/>
    <DC.Language>en</DC.Language>
    <DC.Relation/>
    <DC.Coverage/>
    <DC.Rights>
      Copyright (c) 2004 California Institute of Technology.
      All rights reserved.
    </DC.Rights>
    <Version>1.0</Version>
  </metadata>
</dataDictionary>
        

The following is an example of how to execute the add event from the command-line. This command will register the test_schema.xsd file with metadata contained in the test_metadata.xml file with the Schema Registry.

% java \
-classpath /usr/local/metadata/etc \
-Djava.ext.dirs=/usr/local/metadata/lib \
-Djpl.eda.Configuration.file=/usr/local/metadata/etc/edarc.xml \
jpl.eda.metadata.registry.schema.SchemaClient \
urn:eda:corba:JPL.EDM.MetadataRegistry add \
test_metadata.xml test_schema.xsd
        

Release Event

This event enables a versioned schema file to be promoted or released. This action entails updating the schema's status from REGISTERED to RELEASED and the schema file is copied from its version specific directory to the parent directory in the hierarchy. The additional command-line arguments are as follows:

The following is an example of how to execute the release event from the command-line. The first command will promote the schema identified by JPL.Test.Schema with version 1.0 while the second command will promote the schema with registry identifier 99 in the Schema Registry.

% java \
-classpath /usr/local/metadata/etc \
-Djava.ext.dirs=/usr/local/metadata/lib \
-Djpl.eda.Configuration.file=/usr/local/metadata/etc/edarc.xml \
jpl.eda.metadata.registry.schema.SchemaClient \
urn:eda:corba:JPL.EDM.MetadataRegistry release \
JPL.Test.Schema 1.0

Optionally:

% java \
-classpath /usr/local/metadata/etc \
-Djava.ext.dirs=/usr/local/metadata/lib \
-Djpl.eda.Configuration.file=/usr/local/metadata/etc/edarc.xml \
jpl.eda.metadata.registry.schema.SchemaClient \
urn:eda:corba:JPL.EDM.MetadataRegistry release \
99