Creating a Wildfly Docker image with TimescaleDB support

Edoardo 🇮🇹 Aug 4, 2021 4 min read
Table of Contents

Introduction #

In this post, I will guide you through the process of creating a Wildfly Docker image with complete support for the popular time-series database, TimescaleDB, and how to easily combine the two using Docker Compose.

Wildfly docker image #

As a base image, we’ll use the latest official Wildfly docker image, named jboss/wildfly:24.0.0.Final. Since TimescaleDB relies on PostgreSQL, we also need to setup the PostgreSQL driver and datasource in Wildfly. This requires the following:

  • Download PostgreSQL driver from the official maven repository
  • Adding PostgreSQL module
  • Adding PostgreSQL driver
  • Setup a main Datasource

Luckily, all these steps can be automated using jboss cli (located at /opt/jboss/wildfly/bin/jboss-cli.sh).

Here’s the full Dockerfile:

 1FROM jboss/wildfly:24.0.0.Final
 2 
 3ENV WILDFLY_USER admin
 4ENV WILDFLY_PASS password
 5ENV JBOSS_CLI /opt/jboss/wildfly/bin/jboss-cli.sh
 6ENV DEPLOYMENT_DIR /opt/jboss/wildfly/standalone/deployments/
 7 
 8ENV DB_NAME sample-db
 9ENV DB_USER postgres
10ENV DB_PASS postgres
11ENV DB_HOST db
12ENV DB_PORT 5432
13ENV POSTGRESQL_VERSION 42.2.23
14 
15RUN echo "Building wildfly"
16RUN echo "=> Adding administrator user"
17RUN $JBOSS_HOME/bin/add-user.sh -u $WILDFLY_USER -p $WILDFLY_PASS --silent
18 
19RUN echo "=> Starting WildFly server" && \
20      bash -c '$JBOSS_HOME/bin/standalone.sh &' && \
21    echo "=> Waiting for the server to boot" && \
22      bash -c 'until `$JBOSS_CLI -c ":read-attribute(name=server-state)" 2> /dev/null | grep -q running`; do echo `$JBOSS_CLI -c ":read-attribute(name=server-state)" 2> /dev/null`; sleep 1; done' && \
23    echo "=> Downloading PostgreSQL driver" && \
24      curl -k --location --output ./postgresql-${POSTGRESQL_VERSION}.jar --url https://repo1.maven.org/maven2/org/postgresql/postgresql/${POSTGRESQL_VERSION}/postgresql-${POSTGRESQL_VERSION}.jar && \
25    echo "=> Adding PostgreSQL module" && \
26      $JBOSS_CLI --connect --command="module add --name=org.postgresql --resources=./postgresql-${POSTGRESQL_VERSION}.jar --dependencies=javax.api,javax.transaction.api" && \
27    echo "=> Adding PostgreSQL driver" && \
28      $JBOSS_CLI --connect --command="/subsystem=datasources/jdbc-driver=postgresql:add(driver-name=postgresql,driver-module-name=org.postgresql,driver-class-name=org.postgresql.Driver,driver-xa-datasource-class-name=org.postgresql.xa.PGXADataSource)" && \
29    echo "=> Adding main Datasource" && \
30      $JBOSS_CLI --connect --command="data-source add \
31        --name=PostgresDS \
32        --jndi-name=java:jboss/datasources/PostgresDS \
33        --user-name=${DB_USER} \
34        --password=${DB_PASS} \
35        --driver-name=postgresql \
36        --connection-url=jdbc:postgresql://${DB_HOST}:${DB_PORT}/${DB_NAME} \
37        --use-ccm=false \
38        --blocking-timeout-wait-millis=5000 \
39        --enabled=true" && \
40    echo "=> Shutting down WildFly and Cleaning up" && \
41      $JBOSS_CLI --connect --command=":shutdown" && \
42      rm -rf $JBOSS_HOME/standalone/configuration/standalone_xml_history/ $JBOSS_HOME/standalone/log/* && \
43      rm -f ./*.jar
44 
45EXPOSE 8080 9990 5005
46 
47CMD ["/opt/jboss/wildfly/bin/standalone.sh", "-b", "0.0.0.0", "-bmanagement", "0.0.0.0", "--debug", "*:5005"]

The following ports are exposed:

  • 8080 for the application
  • 9990 for the admin console
  • 5005 for debugging

Remember to specify the correct datasource in your project’s persistence.xml file:

1<persistence-unit name="...">
2    <jta-data-source>java:jboss/datasources/PostgresDS</jta-data-source>
3    ...
4</persistence-unit>

Docker Compose #

For the docker-compose file, there are two services required:

  • The modified Wildfly image with Timescale support, as seen above
  • The Timescale instance

Both services are fully configurable through environment variables and are able to communicate using Docker’s bridge networks. Here’s the full docker-compose.yml:

 1version: "2"
 2 
 3services:
 4  wildfly:
 5    container_name: "wildfly"
 6    build:
 7      context: .
 8      dockerfile: Dockerfile
 9    environment:
10      - WILDFLY_USER=admin
11      - WILDFLY_PASS=password
12      - DB_NAME=sample-db
13      - DB_USER=postgres
14      - DB_PASS=postgres
15      - DB_HOST=db
16      - DB_PORT=5432
17    depends_on:
18      - db
19    volumes:
20      - ./workdir/deploy/wildfly/:/opt/jboss/wildfly/standalone/deployments/:rw
21    ports:
22      - "8080:8080"
23      - "9990:9990"
24      - "5005:5005"
25 
26  db:
27    container_name: "db"
28    image: "timescale/timescaledb:latest-pg13"
29    environment:
30      - POSTGRES_DB=sample-db
31      - POSTGRES_USER=postgres
32      - POSTGRES_PASSWORD=postgres
33    volumes:
34      - ./workdir/db/init/:/docker-entrypoint-initdb.d/
35      - ./workdir/db/data/:/var/lib/postgresql/
36    ports:
37      - "5432:5432"
38 
39networks:
40  default:
41    driver: bridge

Note that:

  • Wildfly image is automatically fetched from the Dockerfile, which should be in the same folder as the docker-compose.yml
  • Thanks to docker’s volume mapping, you can add .war files in the workdir/deploy/wildfly and they will be deployed to Wildfly automatically
  • Database data is persisted in the workdir/db folder even when the container is destroyed. However, remember to set hibernate.hbm2ddl.auto property to update in your persistence.xml file, in order to avoid losing your data between launches.

To start the services, simply run docker-compose up from any terminal instance.

Enabling TimescaleDB Hypertables in Java #

First, create a class named CustomPostgreSQLDialect that extends PostgreSQL95Dialect and registers the OTHER sql type as a String:

1import org.hibernate.dialect.PostgreSQL95Dialect;
2import java.sql.Types;
3 
4public class CustomPostgreSQLDialect extends PostgreSQL95Dialect { 
5    public CustomPostgreSQLDialect() {
6        super();
7        registerHibernateType(Types.OTHER, String.class.getName());
8    }
9}

This is required since Timescale’s create_hypertable return value is not natively supported by Hibernate. If you skip this step, you’ll most likely end up with an error such as:

javax.persistence.PersistenceException: org.hibernate.MappingException: No Dialect mapping for JDBC type: 1111

Then, specify CustomPostgreSQLDialect as the Hibernate dialect in your project’s persistence.xml file:

1<persistence-unit name="...">
2    <properties>
3        ...
4        <property name="hibernate.dialect" value="CustomPostgreSQLDialect"/> 
5        ...
6    </properties>
7</persistence-unit>

Finally, enable TimescaleDB extension on the database and then create the hypertable:

1// Enable TimescaleDB extension
2entityManager.createNativeQuery("CREATE EXTENSION IF NOT EXISTS timescaledb;").executeUpdate();
3 
4// Create hypertable
5String result = entityManager.createNativeQuery(
6        "SELECT create_hypertable('YOUR_TABLE_HERE', 'YOUR_TIME_COLUMN_HERE')"
7).getSingleResult().toString();
8 
9LOGGER.info(String.format("Result: %s", result));

If all went well, you should see something like this in the logs:

Result: (1,public,YOUR_TABLE_HERE,t)
Example terminal output

For more details on hypertables refer to the offical TimescaleDB documentation.

References #