Quarkus NewsStand application

This project is an application that performs web-scraping of news-sites and displays a simpler view of the articles.

This is a Quarkus application using MicroProfile Reactive Messaging, originally taken from AMQP-Quickstart example of Quarkus.

The original quickstart was changed so that all "queues" are internal (in-memory), and no Broker is needed! .

AMQP Broker

I have modified this example so it does NOT nead any AMQP broker! All "queues" are internal "in-memory" queues (using Vert.x Event Bus)

Start the application

This application uses Java 11. If you run with Java 8, you will receive build errors.

To make sure you are using Java 11, do:

evyatar@evyatar-xps:~/work/quarkus/news-quarkus$ sudo update-alternatives --config java
[sudo] password for evyatar: 
There are 3 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                            Priority   Status
------------------------------------------------------------
  0            /usr/lib/jvm/java-11-openjdk-amd64/bin/java      1111      auto mode
* 1            /usr/lib/jvm/java-11-openjdk-amd64/bin/java      1111      manual mode
  2            /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java   1081      manual mode
  3            /usr/lib/jvm/java-8-oracle/jre/bin/java          1081      manual mode

and make sure you select a Java 11.

In addition, set JAVA_HOME to point to the same JDK:

evyatar@evyatar-xps:~/work/quarkus/news-quarkus$ env | grep JAVA
JAVA_HOME=/usr/lib/jvm/java-8-oracle
evyatar@evyatar-xps:~/work/quarkus/news-quarkus$ export JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64
evyatar@evyatar-xps:~/work/quarkus/news-quarkus$ env | grep JAVA
JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64
evyatar@evyatar-xps:~/work/quarkus/news-quarkus$

The application can be started (from a terminal) using:

mvn quarkus:dev

Then, open your browser to http://localhost:8080/prices.html, and you should see a fluctuating price.

As a simpler test, the endpoint (GET) http://localhost:8080/prices returns "hello"

Anatomy

In addition to the prices.html page, the application is composed by 3 components:

• PriceGenerator - a bean generating random price. They are sent to an internal channel.
• PriceConverter - on the consuming side, the PriceConverter receives the message from the channel and convert the price. The result is sent to an in-memory stream of data
• PriceResource - the PriceResource retrieves the in-memory stream of data in which the converted prices are sent and send these prices to the browser using Server-Sent Events.

The interaction with "queues" is managed by MicroProfile Reactive Messaging. The configuration is located in the application configuration. (in the configuration, I have removed definition of AMQP Broker!)

In this example - do NOT run any Broker using docker-compose - it is not needed, and will not be used anyway!!