jta-quickstart

Quarkus guide: https://quarkus.io/guides/transaction

This quickstart shows how to JTA transactions with core quarkus features like JAX-RS and async support. It does not perform actual transactional work since there are other quickstarts and extensions for that (such as hibernate-orm, hibernate-reactive, agroal, etc).

It uses

• RESTEasy to expose REST endpoints which demonstrate various aspects of transactional behaviour
• REST-assured and JUnit 5 for endpoint testing

Requirements

To compile and run this demo you will need:

• JDK 1.8+
• GraalVM

Configuring GraalVM and JDK 1.8+

Make sure that both the GRAALVM_HOME and JAVA_HOME environment variables have been set, and that a JDK 1.8+ java command is on the path.

See the Building a Native Executable guide for help setting up your environment.

Building the application

Launch the Maven build on the checked out sources of this demo:

./mvnw package

This command will build the example and run the tests.

Live coding with Quarkus

The Maven Quarkus plugin provides a development mode that supports live coding. To try this out:

./mvnw quarkus:dev

This command will leave Quarkus running in the foreground listening on port 8080.

Run Quarkus in JVM mode

When you're done iterating in developer mode, you can run the application as a conventional jar file.

An alternative to running the tests is to use a tool such as curl to exercise the endpoints:

java -jar ./target/jta-1.0-SNAPSHOT-runner.jar

non transactional

curl -XGET http://0.0.0.0:8080/jta # This should return the value 6 which corresponds to no transaction

Do transactional work by annotating a resource method with @Transactional (the framework will manage the transaction boundaries):

curl -XPOST http://0.0.0.0:8080/jta/cmt # this should return 0 which corresponds to an active transaction

Do transactional work by explicitly managing the transaction boundaries:

curl -XPOST http://0.0.0.0:8080/jta/bmt # This should return the value 6 which corresponds to no transaction

Do transactional work in an asynchronous JAX-RS method using AsyncResponse and MicroProfile Context Propagation:

curl -XPOST http://0.0.0.0:8080/jta/async-with-suspended # This should return the value 3 which corresponds to an transaction

Do transactional work in a completion stage:

curl -XPOST http://0.0.0.0:8080/jta/async-with-completion-stage # this should return 0 which corresponds to an active transaction

There is also an endpoint for reproducing an open quarkus issue (6471). It is disabled in the tests pending the fix:

curl -XPOST http://0.0.0.0:8080/jta/async-6471-reproducer

Run Quarkus as a native executable

You can also create a native executable from this application without making any source code changes. A native executable removes the dependency on the JVM: everything needed to run the application on the target platform is included in the executable, allowing the application to run with minimal resource overhead.

Compiling a native executable takes a bit longer, as GraalVM performs additional steps to remove unnecessary codepaths. Use the native profile to compile a native executable:

./mvnw package -Dnative

and then run this executable directly:

./target/jta-quickstart-1.0-SNAPSHOT-runner