Thursday, 21 December 2017

2017: A busy year for Infinispan evangelisation!

It's been a very busy year from an Infinispan evangelisation perspective, so before the year ends, we wanted to round up the conferences and user groups that featured Infinispan related talks. This is a good opportunity to catch up on what we've been showing in our Infinispan outings:

Patterns d’utilisation de systèmes in memory 

by Emmanuel Bernard and Galder Zamarreño
@ Devoxx France

This was our first outing of the year with Emmanuel and I showing the audience at Devoxx France the different use cases for data grids. This was also the first time we showed swiss train related demos which we'd improve throughout the year. Slides can be found here and video below:


Big Data In Action with Infinispan

by Galder Zamarreño
@ Great Indian Developer Summit
@ Berlin Buzzwords
@ Red Hat DevNation Live

In this talk, I focused on the big data related use cases for Infinispan. I showed how Infinispan could be used for near real-time data processing using Continuous Querys, and how to analise data using distributed Java Streams. Slides can be found here and the demo here. The video from the DevNation talk can be found here:


HACEP: Highly available and horizontally scalable complex event processing

by Ugo Landini, Sanne Grinovero, Andrea Leoncini, Andrea Tarocchi
@ Red Hat Summit

In this hands on lab, Ugo et al showed how to build a highly available and scalable complex event processing engine with Red Hat JBoss BRMS and and Red Hat JBoss Data Grid (the commercial supported version of Infinispan). This workshop resulted in unmissable architecture reference guide.

Learn how to build Functional Reactive Applications with Elm, Node.js and Infinispan

by Galder Zamarreño
@ Great Indian Developer Summit
@ J On The Beach

The aim of this talk is to demonstrate how Infinispan's Node.js client could be combined with Elm and Infinispan server instances to build a functional reactive application. The talk focused on how build a CRUD application using Elm and Node.js technologies and using Infinispan in-memory data grids for storing and querying information. Slides can be found here:


Streaming Data Analysis with Kubernetes

by Galder Zamarreño

This talk is a spin off of the big data in action talk which focuses on exploring in greater detail how streaming data can be analysed within a Kubernetes orchestrated cluster. The demo can be found here and the slides here:

Data grids : descubre qué esconden los datos

by Galder Zamarreño

This talk is a Spanish spin off the analytics part of the big data in action talk. Not only did it showed how to use distributed Java Streams to analyse data with Infinispan, but also demonstrated the capabilities of Spark/Hadoop integrations. The demos can be found here and here, and the slides here:


Streaming Data : ni pierdas el tren, ni esperes en balde

by Galder Zamarreño

A Spanish version of the streaming data analysis talk delivered in Basel One. This talk was recorded, so hoping for the video to be available soon. In the mean time, the demo can be found here and the slides here:

Streaming Data Workshop

by Katia Aresti, Thomas Segismont and Galder Zamarreño

A hands-on workshop showing how to work with streaming data with Infinispan and Vert.x, on top of OpenShift container platform. No videos were recorded but you can follow this workshop step by step following instructions here. The Github repository can be found here and the latest slides here:


There's plenty the to keep you entertained between now and the new year! :)

If you have any doubts about the talks above, or you encounter any issues running the demos, do not hesitate contacting us! In the mean time, the Infinispan team is working hard on Infinispan 9.2 as well as improving our OpenShift integration.

Cheers,
Galder


Tuesday, 19 December 2017

Infinispan 9.1.4.Final Released

Dear Infinispan Community,

We're excited to announce the release of Infinispan 9.1.4.Final, which can be found on our download page.

Full details of the various fixes included in this release can be found here.

Monday, 18 December 2017

Infinispan 9.2.0.Beta2 Released

Dear Infinispan Community,

We're excited to announce the release of Infinispan 9.2.0.Beta2, which can be found on our download page.

The highlights of 9.2.0.Beta2 are:

  • MultiMaps are now available over hotrod [ISPN-7887].
  • Clustered Counters are now available in the server and can be managed via the management api [SPN-8376] or the web console [ISPN-7927].
  • Biased reads in scattered cache [ISPN-8458].
  • Conflict resolution on partition merges are now implemented for DENY_READ_WRITES and ALLOW_READS strategies [ISPN-8440].

Full details of the new features and enhancements included in this release can be found here.
Thank you for following us and stay tuned!

The Infinispan Team

Thursday, 14 December 2017

First steps with Vert.x and Infinispan - PUSH API (Part 2)

Welcome to the second in a multi-part series of blog posts about creating Eclipse Vert.x applications with Infinispan. In the previous blog post we have seen how to create a REST API. The purpose of this tutorial is to showcase how to create a PUSH API implemented with Vert.x and using Infinispan as a server.
All the code of this tutorial is available in this GitHub repository. The backend is a Java project using Maven, so all the needed dependencies can be found in the pom.xml. The front is a super simple react application.


PUSH API

Creating a REST API is very straightforward. But today, even if we are heavily using REST, we don't always want to use request/response or polling, but instead we want to push directly from the server to the client. In this example, we are going to create an API that pushes every new value inserted in the default cache of Infinispan. These values are cute names, as we did in the REST API example.

We are using two features here :
  • Infinispan client listeners
  • Vert.x bridge between the Event Bus and the browser
Infinispan Listeners provide a way to the client get notified when something happens in a cache.

The Event Bus Bridge that connects to the browser, uses SockJS. SockJS is a JavaScript library that provides a WebSocket API, but it can be used with browsers that don't support web-sockets (see the website of the project for more detailed information). Vert.x supports this library and creates a bridge between your browser and your back-end easily through the Event Bus.

Creating an Event Bus bridge


Vert.x is a reactive framework, which means that uses RxJava too, and provides a fancy API on top of it.

First, we are going to create a new verticle called SendCuteNamesAPI. This verticle extends the CacheAccessVerticle we created in the previous blog postCacheAccessVerticle initialises the connection with Infinispan using the Hot Rod protocol.

Now we need to create a SocketJSHandler. This handler has a method called bridge, where we configure some BridgeOptions. Obviously we don't want the client to be able to read everything traveling on the event bus, and this won't happen. We configure an address, 'cute-names', and we add the permission to read and write to this address.

This handler is passed to the event bus route, where the path is /eventbus/*.

Finally, we create a http server as we did in the REST API example. The difference is that instead of calling listen method, we call rxListen and subscribe.



Getting notified and publishing


Using Infinispan listeners is very easy.

First, we are going to create a class that has the @ClientListener annotation. The client listener has to be added to the cache client configuration. We add a protected method called addConfigToCache that will be called just after the initialisation of the defaultCache in the abstract CacheAccessVerticle. Verticles extending the abstract class can now add custom configuration to the client.

We want to be notified when a new entry is created. In this case, our listener has to contain a method with the @ClientCacheEntryCreated annotation on it. The signature of the method has to include a ClientCacheEntryCreatedEvent<String> parameter. This parameter will hold the 'key' of the entry that has been created.

Finally, we use the key to retrieve the name using the getAsync method and then publish the value in the Vert.x event bus to the address where the socket listener is permitted to readcute-names.


Now we can run the main method and whenever we post a new name, we will see in the logs that the client listener is notified!




Client code


We are going to create a super simple react application that will just display hello. React community is *huge*, so there are lot's of tutorials out there to create a hello world client application. This application has a single component that displays "Hello".

The react application runs calling npm install and npm start  in http://localhost:9000/.

Now we need to connect the client to the backend with SockJS. Vert.x provides a JavaScript library for that: vertx3-eventbus-client, built on top of SockJS. We create an EventBus object that will connect to http://localhost:8082/eventbus as we configured in the SendCuteNamesAPI. We register a handler on the 'cute-names' address. The body of the message will contain the new cute name published in the event bus. Every time the handler is called, we update the component's state, and it will be rendered.



Wrap up

We have learned how to create PUSH APIs with Vert.x, powered by Infinispan. The repository has some unit tests. Feedback is more than welcome to improve the code and the provided examples. I hope you enjoyed this tutorial ! On the next tutorials we will talk about Infinispan as the cluster manager for Vert.x. Stay tuned !


Tuesday, 12 December 2017

First steps with Vert.x and Infinispan - REST API (Part 1)

Welcome to the first in a multi-part series of blog posts about creating Eclipse Vert.x applications with Infinispan. The purpose of this first tutorial is to showcase how to create a REST API.
All the code of this tutorial is available in this GitHub repository. The backend is a Java project using Maven, so all the needed dependencies can be found in the pom.xml.

What is Vert.x ?

Vert.x is a tool-kit for building reactive applications on the JVM. It’s an event driven and non blocking tool-kit. It is based on the Reactor Pattern, like Node.js, but unlike Node it can easily use all the cores of your machine so you can create highly concurrent and performant applications. Code examples can be found in this repository.


REST API

Let’s start creating a simple endpoint that will display a welcome message on '/'. In Vert.x this is done by creating a Verticle. A verticle is a unit of deployment and processes incoming events over an event-loop. Event-loops are used in asynchronous programming models. I won't spend more time here explaining these concepts as this is very well done in this Devoxx Vert.x talk or in the documentation available here.

We need to override the start method, create a 'router' so '/' requests can be handled, and finally create a http server.

The most important thing to remember about vert.x, is that we can NEVER EVER call blocking code (we will see how to deal with blocking API's just after). If we do so, we will block the event loop and we won't be able to serve incoming requests properly.



Run the main method, go to your browser to http://localhost:8081/ and we see the welcome message !

Connecting with Infinispan


Now we are going to create a REST API that uses Infinispan. The purpose here is to post and get names by id. We are going to use the default cache in Infinispan for this example, and we will connect to it remotely. To do that, we are going to use the Infinispan hotrod protocol, which is the recommended way to do it (but we could use REST or Memcached protocol too)

Start Infinispan locally

The first thing we are going to do is to run an Infinispan Server locally. We download the Infinispan Server from here, unzip the downloaded file and run ./bin/standalone.sh
If you are using Docker on Linux, you can use the Infinispan Docker Image Available easily. If you are using Docker for Mac, at the time of this writing there is an issue with internal IP addresses and they can't be called externally. Different workarounds exist to solve the problem, but the easiest thing for this example is simply downloading and running the standalone server locally. We will see how to use the docker image in Openshift just after.
The hotrod server is listening in localhost:11222.

Connect the client to the server

The code we need to connect with Infinispan from our java application is the following :



This code is blocking. As I said before, we can't block the event loop and this will happen if we directly call these API's from a verticle. The code must be called using vertx.executeBlocking method, and passing a Handler. The code in the handler will be executed from a worker thread pool and will pass the result back asynchronously.
Instead of overriding the start method, we are going to override start(Future<Void> startFuture). This way, we are going to be able to handle errors.

To stop the client, the API supplies a non blocking method that can be called when the verticle is stopped, so we are safe on that.

We are going to create an abstract CacheAccessVerticle where we will initialise the manager and get default cache. When everything is correct and the defautCache variable is initialised, we will log a message and execute the initSuccess abstract method.


REST API to create names


We are going to add 3 new endpoints.
  • GET /api displays the API name
  • POST /api/cutenames creates a new name
  • GET /api/cutenames/id displays a name by id
CuteNamesRestAPI verticle can now extend this class and override the initSuccess method instead of the start method.



POST

Our goal is to use a curl to create a name like this :

curl -X POST \ 
-H "Content-Type: application/json" \
-d '{"name":"Oihana"}' "http://localhost:8081/api/cutenames"

For those that are not familiar with basques names, Oihana means 'rainforest' and is a super cute name. Those who know me will confirm that I'm absolutely not biased making this statement.
To read the body content, we need to add a body handler to the route, otherwise the body won't be parsed. This is done by calling router.route().handler(BodyHandler.create()).

The handler that will handle the post method in '/api/cutenames' is a RoutingContext handler. We want to create a new name in the default cache. For that, we will call putAsync method from the defaultCache.



The server responds 201 when the name is correctly created, and 400 when the request is not correct.

GET by id

To create a get endpoint by id, we need to declare a route that will take a parameter :id. In the route handler, we are going to call getAsync method.



If we run the main, we can POST and GET names using curl !

 curl -X POST -H "Content-Type: application/json" \
 -d '{"id":"42", "name":"Oihana"}' \ 
"http://localhost:8081/api/cutenames" 

Cute name added 

 curl -X GET -H "Content-Type: application/json" \ 
"http://localhost:8081/api/cutenames/42"

{"name":"Oihana"}

Wrap up

We have learned how to create a REST API with Vert.x, powered by Infinispan. The repository has some unit tests using the web client. Feedback is more than welcome to improve the code and the provided examples. I hope you enjoyed this tutorial ! On the next tutorial you will learn how to create a PUSH API.