context-propagation

Quarkus - Context Propagation

Requirements

To compile and run this demo you will need:

• JDK 1.8+
• GraalVM
• Docker (and Docker Compose)
• httpie (or curl)

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.

Running the demo

Prepare Kafka and PostGreSQL

Just use the docker-compose.yaml file provided in the source:

docker-compose up

Running the demo

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

./mvnw quarkus:dev

Then, you need 2 terminals. In the first one, run:

http :8080/prices --stream

This command streams the next 3 prices.

Send the prices from another terminal with:

http POST :8080 value:=34 http POST :8080 value:=35 http POST :8080 value:=36

The first terminal should have displayed the prices and returns to the prompt. Then run, from any terminal:

http :8080/prices/all

It should display the persisted prices. These prices are only persisted when the streams completes (so after having received 3 prices).

Run Quarkus as a native application

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

After getting a cup of coffee, you'll be able to run this binary directly:

./target/context-propagation-quickstart-1.0-SNAPSHOT-runner