Apache OODT XMLPS is an extensible, configurable product and profile server that easily exposes DBMS-backed repositories and catalogs, respectively, over a REST-ful interface.

XMLPS grew out of the EDRN Informatics Center and its EDRN Resource Network Exchange (ERNE) project.

Here's a quick step guide to getting XMLPS up and running on your project.

Get and Build Apache OODT Web-Grid

To get started with Apache OODT XMLPS, you'll need to install Apache OODT Web Grid.

  1. git clone https://git-wip-us.apache.org/repos/asf/oodt.git
  2. cd grid
  3. mvn install (builds target/web-grid-0.11-SNAPSHOT.war)

You're done here for now, let's go grab Apache Tomcat.

Grab Apache Tomcat and install it

Grab Apache Tomcat. I prefer the 5.5.x series. For those 6.x and 7.x fanboys, instructions will likely be similar.

  1. curl -O http://archive.apache.org/dist/tomcat/tomcat-5/v5.5.36/bin/apache-tomcat-5.5.36.tar.gz
  2. mv apache-tomcat-5.5.36.tar.gz /usr/local
  3. cd /usr/local ; tar xzvf apache-tomcat-5.5.36.tar.gz
  4. ln -s /usr/local/apache-tomcat-5.5.36 tomcat5
  5. edit /usr/local/tomcat5/conf/tomcat-users.xml and add a new user "xmlps" with password "secret" with the roles="manager,admin"

You're done for now with the Tomcat installation. Time to layer the web-grid substrate on top of it.

Layering Apache OODT Web Grid on top of Tomcat

  1. copy web-grid-0.5.war from the target directory from your built Web-Grid to /usr/local/tomcat5/webapps/grid.war (yes rename it, you'll thank me later)

    Warning

    Make sure Tomcat isn't running until the guide says for you to turn it on. Tomcat doesn't like you messing with its webapp and work directories.

Building and Installing XMLPS

  1. git clone https://git-wip-us.apache.org/repos/asf/oodt.git
  2. cd xmlps
  3. mvn install assembly:assembly (builds target/oodt-xmlps-0.5-with-dependencies.jar)
  4. create deploy area, e.g., /usr/local/xmlps and copy oodt-xmlps-0.5-with-dependencies.jar to it
  5. copy example conf files out of xmlps/src/main/conf (example.db.properties and example-ps.xml) into /usr/local/xmlps

Set up a database

Let's assume you have installed MySQL. There are plenty of guides out there to do so (including the one I just linked to) for specific operating systems, etc. So assuming that you have MySQL already installed, let's create a quick database and sample schema and user.

  1. Create a MySQL database with user xmlps and password xmlps and add some sample data.

    CREATE DATABASE xmlps;
GRANT ALL PRIVILEGES ON xmlps.* TO 'xmlps'@'localhost' IDENTIFIED BY 'xmlps';
GRANT ALL PRIVILEGES ON xmlps.* TO 'xmlps'@'%' IDENTIFIED BY 'xmlps';

  2. Log on to MySQL with user xmlps

    mysql -u xmlps xmlps -p

    (enter password "xmlps")

  3. Create a simple data product schema

    CREATE TABLE products (product_id int auto_increment NOT NULL PRIMARY KEY, product_name varchar(255));

  4. INSERT 2 rows of data into the table

    INSERT INTO products (product_name) VALUES ('Test1');
INSERT INTO products (product_name) VALUES ('Test2');

Download the MySQL connector JAR and install it

You can grab version 5 of the MySQL JAR connector and it should work fine. If it doesn't, grab one of the appropriate versions for your MySQL DB.

  1. curl -O http://repo1.maven.org/maven2/mysql/mysql-connector-java/5.1.6/mysql-connector-java-5.1.6.jar
    Now you have to unzip grid.war that you installed in Tomcat, and install the JDBC driver to its WEB-INF/lib directory
  2. cd /usr/local/tomcat5/webapps/ ; unzip grid.war
    Now copy the JDBC jar file to the unzipped grid's WEB-INF/lib directory
  3. cp mysql-connector-java-5.1.6.jar /usr/local/tomcat5/grid/WEB-INF/lib

Configure XMLPS to talk to your MySQL DB

Now that everything is installed, and that you have a DB, you'll need to configure XMLPS to talk to your backend MySQL db. The first step is to configure the DB connection.

  1. Edit /usr/local/xmlps/example.db.properties.

    # Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# Example data source configuration file

xmlps.datasource.jdbc.url=jdbc:mysql://localhost:3306/xmlps?autoReconnect=true
xmlps.datasource.jdbc.user=xmlps
xmlps.datasource.jdbc.pass=xmlps
xmlps.datasource.jdbc.driver=com.mysql.jdbc.Driver

  2. Expose the underlying data from the DB by editing the /usr/local/xmlps/example-ps.xml. We're going to rename the product_id field to "id" and the product_name field to "name" and add a constant field representing the data quality (called "quality_flag"), giving it the value "sample" to indicate this is just a test.

    <?xml version="1.0" encoding="UTF-8"?>
<!--
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements.  See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License.  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<oodt:xmlps xmlns:oodt="http://incubator.apache.org/oodt/0.1-incubating"
	name="My Query Handler" id="myqueryhandler">
	<tables default="products">
	</tables>
	<field type="dynamic" name="id" dbname="product_id" />
	<field type="dynamic" name="name" dbname="product_name"/>
	<field type="constant" name="quality_flag" value="sample" />
</oodt:xmlps>

Now XMLPS is configured to talk to the DB and to map the values and names from the underlying database to a common language (id, name and quality_flag rather than product_id and product_name in relational database ville).

Startup and visit your Tomcat server

OK it's actually time to start Tomcat.

  1. cd /usr/local/tomcat5/bin ; ./startup.sh
    Now visit http://localhost:8080/grid/
  2. Click the Configure tab and enter the default Web-Grid password (you can find it here on slide 25) – you'll end up on a screen like the below.
  3. Scroll down and configure web-grid to use XMLPS handler, and to reference XMLPS jar file in /usr/local/xmlps

  4. Add the 2 properties ("org.apache.oodt.xmlps.xml.mapFilePath" set to /usr/local/xmlps/example-ps.xml and "org.apache.oodt.xmlps.xml.dbPropFilePath" set to /usr/local/xmlps/example.db.properties). This binds your XMLPS to the configuration files that you edited previously to connect to the DB and unlock its information.

Issue a Query against XMLPS

Now that you have XMLPS and Web-Grid configured, Tomcat running, etc., it's time to issue a query against it! Try a query for name=Test2 (should only return the 2nd product):

  1. curl http://localhost:8080/grid/prod?q=RETURN%3Did+AND+RETURN%3Dname+AND+name=%27Test2%27

    2    Test2$
  2. you can also tell it to return other fields, like the constant field tag

  3. curl http://localhost:8080/grid/prod?q=RETURN%3Did+AND+RETURN%3Dname+AND+name=%27Test2%27+AND+RETURN%3Dquality_flag

    2    Test2     sample$

That's it! You're up and running!

Other Relevant Reading

  1. Mattmann's original guide for XMLPS (12 steps)
  2. Mailing list conversation/chatter about installing XMLPS
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