Welcome!

AJAX & REA Authors: Scott Hirsch, Trevor Parsons, David H Deans, Carmen Gonzalez, Pat Romanski

Related Topics: Java, XML, SOA & WOA, .NET, AJAX & REA, Web 2.0

Java: Blog Feed Post

Building a Simple Peer-to-Peer WebSocket App – Part 1

A Step-by-Step Tutorial

This tutorial series walks you through the simple steps of building an HTML5 WebSocket app, demonstrating the power of the publish/subscribe development pattern directly in JavaScript. Our sample is almost as simple as a Chat app, the “Hello World” app of the WebSocket world, but is a tad more visual and dynamic.

After trying out the completed application, you can either jump in the code and play with it right away, or move on to Part 2 (coming soon) of this tutorial for a step-by-step guide.

About the Environment
This tutorial requires a WebSocket server. We will use http://tutorial.kaazing.com, which hosts the JMS Edition of Kaazing WebSocket Gateway, Kaazing’s high-performance enterprise-grade WebSocket Server. All you’ll need to do is create a WebSocket connection to this server directly from your browser and start “talking” (read: send messages) to it from your browser. On the client side, you can use any modern browser, supported by JSFiddle (learn more about JSFiddle).

Getting Started
First, to understand how the tutorial environment in JSFiddle works, open up the completed demo in JSFiddle. If you’re using a tablet or a smart phone, use the full page mode of the demo.

JSFiddle provides a simple, integrated environment to edit the source of your web pages and apps. It has four panes:

  • Top-left: HTML code (very minimal HTML code in our demo)
  • Bottom-left: JavaScript code
  • Top-right: CSS code (empty in our case)
  • Bottom-right: Result

In the bottom right pane, you can interact with the completed app. Using the slider, you can change the size of the image. Now, open another browser window, pointing to the same JSFiddle demo URL. You can also use a tablet or a smart phone. Position your two browser windows side-by-side. As you adjust the slider in the bottom-right pane, right above the image in one browser window, the slider position and image size change in the other one. They’re kept in sync.

The browsers are communicating with the WebSocket gateway which is running in Amazon’s EC2 cloud, hosted in North Virginia, USA. When you move the slider, messages travel from your browser, to the WebSocket gateway, and back to the other browser.

Watch this video demonstrating the completed application (if the letters are blurry, switching the video to HD helps):

At this point, you can make any changes to the application. Click the Run button to test out your changes. To roll back to the original state, simply reload the original JSFiddle demo URL.

Note: If you see the image resize without you moving the slider, there’s a chance that somebody else is experimenting with the tutorial as well. To ensure that you’re not interfering with anybody else, change the topic name to something unique to you, for example by appending your name. Locate the following line in the bottom-left pane, towards the top of the file:

 

var TOPIC_NAME = "/topic/myTopic";

 

Modify the name of the topic. For example:

 

var TOPIC_NAME = "/topic/PeterTopic";

Test your code by clicking the Run button.

As another test, you can also change the application’s logging behavior. To give it a try, change the value of the IN_DEBUG_MODE variable to false, located in the bottom-left pane towards the top of the file. Original line:

var IN_DEBUG_MODE = true;

After the changes:

var IN_DEBUG_MODE = false;

Test your code by clicking the Run button.

In Part 2 (coming soon) you can learn about the demo code and how quickly and easily you can build real-time web applications with Web messaging.

Read the original blog entry...

More Stories By Jonas Jacobi

Jonas has 21 years of experience leading the development of innovative technology products and services. Together with Kaazing’s Co-Founder & CTO John Fallows, he pioneered and championed the groundbreaking HTML5 WebSocket standard. Prior to co-founding Kaazing he served as VP of Product Management for Brane Corporation, a Silicon Valley startup dedicated to developing a market-leading enterprise platform for building model-driven apps. Before Brane, he spent 8+ years at Oracle where he served as a Java EE and open source Evangelist, and was Product Manager in the Oracle Application Server division for JavaServer Faces, Oracle ADF Faces, and Oracle ADF Faces Rich Client. He is a frequent speaker at international conferences on accelerating and scaling secure enterprise-grade WebComms (Web Communications).

@CloudExpo Stories
SYS-CON Events announced today that Utimaco will exhibit at SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Utimaco is a leading manufacturer of hardware based security solutions that provide the root of trust to keep cryptographic keys safe, secure critical digital infrastructures and protect high value data assets. Only Utimaco delivers a general-purpose hardware security module (HSM) as a customiz...
How do APIs and IoT relate? The answer is not as simple as merely adding an API on top of a dumb device, but rather about understanding the architectural patterns for implementing an IoT fabric. There are typically two or three trends: Exposing the device to a management framework Exposing that management framework to a business centric logic • Exposing that business layer and data to end users. This last trend is the IoT stack, which involves a new shift in the separation of what stuff hap...
SYS-CON Events announced today that SOA Software, an API management leader, will exhibit at SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. SOA Software is a leading provider of API Management and SOA Governance products that equip business to deliver APIs and SOA together to drive their company to meet its business strategy quickly and effectively. SOA Software’s technology helps businesses to accel...
Almost everyone sees the potential of Internet of Things but how can businesses truly unlock that potential. The key will be in the ability to discover business insight in the midst of an ocean of Big Data generated from billions of embedded devices via Systems of Discover. Businesses will also need to ensure that they can sustain that insight by leveraging the cloud for global reach, scale and elasticity.
SYS-CON Events announced today that ElasticBox is holding a Hackathon at DevOps Summit, November 6 from 12 pm -4 pm at the Santa Clara Convention Center in Santa Clara, CA. You can enter as an individual or team of up to 10 developers. A New Star Is Born Every Month! All completed ElasticBoxes will then be sent to a judging panel - 12 winners will be featured on the ElasticBox website in 2015. All entrants will receive five full enterprise licenses for one year + ElasticBox headphones + Elasti...
Once the decision has been made to move part or all of a workload to the cloud, a methodology for selecting that workload needs to be established. How do you move to the cloud? What does the discovery, assessment and planning look like? What workloads make sense? Which cloud model makes sense for each workload? What are the considerations for how to select the right cloud model? And how does that fit in with the overall IT tranformation? In his session at 15th Cloud Expo, John Hatem, head of V...
Cloud services are the newest tool in the arsenal of IT products in the market today. These cloud services integrate process and tools. In order to use these products effectively, organizations must have a good understanding of themselves and their business requirements. In his session at 15th Cloud Expo, Brian Lewis, Principal Architect at Verizon Cloud, will outline key areas of organizational focus, and how to formalize an actionable plan when migrating applications and internal services to...
SAP is delivering break-through innovation combined with fantastic user experience powered by the market-leading in-memory technology, SAP HANA. In his General Session at 15th Cloud Expo, Thorsten Leiduck, VP ISVs & Digital Commerce, SAP, will discuss how SAP and partners provide cloud and hybrid cloud solutions as well as real-time Big Data offerings that help companies of all sizes and industries run better. SAP launched an application challenge to award the most innovative SAP HANA and SAP ...
Ixia develops amazing products so its customers can connect the world. Ixia helps its customers provide an always-on user experience through fast, secure delivery of dynamic connected technologies and services. Through actionable insights that accelerate and secure application and service delivery, Ixia's customers benefit from faster time to market, optimized application performance and higher-quality deployments.
SYS-CON Events announced today that Calm.io has been named “Bronze Sponsor” of DevOps Summit Silicon Valley, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Calm.io is a cloud orchestration platform for AWS, vCenter, OpenStack, or bare metal, that runs your CL tools puppet, Chef, shell, git, Jenkins, nagios, and will soon support New Relic and Docker. It can run hosted, or on premise and provides VM automation / expiry, self-service portals,...
In her General Session at 15th Cloud Expo, Anne Plese, Senior Consultant, Cloud Product Marketing, at Verizon Enterprise, will focus on finding the right mix of renting vs. buying Oracle capacity to scale to meet business demands, and offer validated Oracle database TCO models for Oracle development and testing environments. Anne Plese is a marketing and technology enthusiast/realist with over 19+ years in high tech. At Verizon Enterprise, she focuses on driving growth for the Verizon Cloud pla...
SYS-CON Events announced today that Aria Systems, the recurring revenue expert, has been named "Bronze Sponsor" of SYS-CON's 15th International Cloud Expo®, which will take place on November 4-6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Aria Systems helps leading businesses connect their customers with the products and services they love. Industry leaders like Pitney Bowes, Experian, AAA NCNU, VMware, HootSuite and many others choose Aria to power their recurring revenue bu...
The Internet of Things (IoT) is going to require a new way of thinking and of developing software for speed, security and innovation. This requires IT leaders to balance business as usual while anticipating for the next market and technology trends. Cloud provides the right IT asset portfolio to help today’s IT leaders manage the old and prepare for the new. Today the cloud conversation is evolving from private and public to hybrid. This session will provide use cases and insights to reinforce t...
As Platform as a Service (PaaS) matures as a category, developers should have the ability to use the programming language of their choice to build applications and have access to a wide array of services. Bluemix is IBM's open cloud development platform that enables users to easily build cloud-based, creative mobile and web applications without having to spend large amounts of time and resources on configuring infrastructure and multiple software licenses. In this track, you will learn about the...
Blue Box has closed a $10 million Series B financing. The round was led by a strategic investor and included participation from prior investors including Voyager Capital and Founders Collective, as well as the Blue Box executive team. This round follows a $4.3 million Series A closed in December of 2012 and led by Voyager Capital. In May of this year, the company announced general availability of its private cloud as a service offering, Blue Box Cloud. Since that release, the company has dem...
SYS-CON Events announced today that Verizon has been named "Gold Sponsor" of SYS-CON's 15th International Cloud Expo®, which will take place on November 4-6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Verizon Enterprise Solutions creates global connections that generate growth, drive business innovation and move society forward. With industry-specific solutions and a full range of global wholesale offerings provided over the company's secure mobility, cloud, strategic network...
SimpleECM is the only platform to offer a powerful combination of enterprise content management (ECM) services, capture solutions, and third-party business services providing simplified integrations and workflow development for solution providers. SimpleECM is opening the market to businesses of all sizes by reinventing the delivery of ECM services. Our APIs make the development of ECM services simple with the use of familiar technologies for a frictionless integration directly into web applicat...
The only place to be June 9-11 is Cloud Expo & @ThingsExpo 2015 East at the Javits Center in New York City. Join us there as delegates from all over the world come to listen to and engage with speakers & sponsors from the leading Cloud Computing, IoT & Big Data companies. Cloud Expo & @ThingsExpo are the leading events covering the booming market of Cloud Computing, IoT & Big Data for the enterprise. Speakers from all over the world will be hand-picked for their ability to explore the economic...
Cloudwick, the leading big data DevOps service and solution provider to the Fortune 1000, announced Big Loop, its multi-vendor operations platform. Cloudwick Big Loop creates greater collaboration between Fortune 1000 IT staff, developers and their database management systems as well as big data vendors. This allows customers to comprehensively manage and oversee their entire infrastructure, which leads to more successful production cluster operations, and scale-out. Cloudwick Big Loop supports ...
SAP is delivering break-through innovation combined with fantastic user experience powered by the market-leading in-memory technology, SAP HANA. In his General Session at 15th Cloud Expo, Thorsten Leiduck, VP ISVs & Digital Commerce, SAP, will discuss how SAP and partners provide cloud and hybrid cloud solutions as well as real-time Big Data offerings that help companies of all sizes and industries run better. SAP launched an application challenge to award the most innovative SAP HANA and SAP ...