Considerations for responsiveness of web application using SQLite and Tomcat - spring

I'm planning to create a web based application for restaurant billing for my client. The technology is Spring, hibernate. Since my client is not inclined to any browsers, I will ask him to go with Firefox. Planning to deploy my App in Tomcat instance in his local machine.
This is my first real time deployment. I have planned to use SQLite in Firefox to give at least 70% of responsive time of desktop application. How do I make my application more stable since he will be using it round the clock? Will the responsiveness of my application deteriorate in days? I don't have any clear forecast on this.

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Hosting Spring Boot microservice (REST API) - What are my options?

I have some experience developing microservice using spring boot applications but I'm a beginner when it comes to hosting and deploying those applications.
Below some characteristics of my microservice:
Is a spring boot (tomcat) application (latest version)
The database used to store data it is MySql (latest version)
The source code is on github as VCS
Continue integration tool: TBD
I need at least 2 environments (development and production)
The application currently its address around 3K end-users by year, so the traffic is NOT, unfortunately, a big issue :(
The budget I intend to allocate is up to 200$ by year
Perhaps you could take a shot at hosting it on Microsoft Azure.
Currently they have support for Tomcat and you could try to deploy the app in seconds with their App Services, which can easily be hooked up to a Github repo for continuous deployment. However, you will almost certainly need to dig into the config to make a successful build.
I also think this could be a fitting solution for you, since they offer you the opportunity to try it for free for 12 months, with $200 credit. This appears to fit what you would need for your first year.
If you can make it work under Azure's constraints for the first year, you can evaluate whether you'd like to renew or choose a different provider!
Best of luck to you.

Best Spring MVC,Hibernate,Mysql & Maven application hosting server

I have completed my first web & Mobile project in Spring mvc 3.2.6 + Hibernate + Maven,Mysql & Rest Services.
Now i want to host the application.So that i can hit the webservice via mobile & host the web application.While browsing the google found the following link.
http://aws.amazon.com/free/
https://www.openshift.com/
http://azure.microsoft.com/en-in/pricing/
http://www.rackspace.com/cloud/private
https://www.heroku.com/pricing
https://appengine.google.com/start
So could you please anyone guide which one of the above server is good to host.Right now i am planning to use FREE version of the above server and in future i may use a paid version.Could anyone please which one is best?
I appreciate your answers & suggestion!!!Thank you.
I can say for Openshift. The best features it gave to you is:
No credit card required
No trial time
Doesn't need to sleep
Can scale, you can use up to 3 small gears on free plan, all loadbalanced by default
Many cartridges (like a pre-built package with servers) like MySQL, Mongo, RedisCloud, AMQPCloud, a bunch of others services using the Marketplace with a lot of free ones
Sleep when nobody is using, when someone hit a request the server goes on again , also auto scale up and down
Easy setup and Java ApplicationServers support (Tomcat, JBoss, Wildfly***)
Easy build customization via hooks
You can upgrade to bronze plan without paying a coin using the free gears you have, and you get alot of features
Runs on AWS Infrastructure
EDIT
Think of Gears as machines, it's just a fancy name they give to it, like Heroku named theirs Dynos
Price plans are located here with side by side comparison. You can check the marketplace offers here. Also they have some quick starters, all Java cartridges comes with Java 7 and Maven 3 installed by default. See here for more detailed tech.
They have a developers site with content to get started, help and documentation
** Small gears are machines with 1 CPU, 512Mb of RAM and 1GB disk
*** Wildfly on a free plan takes so much disk space, then is pratical impossible to use, but for paid plans is awesome

Migrate Azure Web Site to Azure Cloud Service

I have a project and I'm planning to start the web app as an Azure Web Site and then migrate it to an Azure Cloud Service (also called Hosted Service) if it is needed as a scale strategy.
The decision is because I read that Azure Web Sites are more simple and fast to develop with almost no Azure-specific configurations or code. So starting fast and simple is a good starting point for the project.
But, is that a good starting point for you?
Is migrating an Azure Web Site to an Azure Cloud Service the same as you were migrating a normal ASP.NET Website to an Azure Cloud Service?
Would you start with an Azure Cloud Service right from the beginning? If yes, why?
Thanks for your time.
There are benefits to both deployment models, it will eventually come down to what you are trying to achieve and ultimately the success of your application.
Below I've outlined the Pros and Cons of each of the models to ensure that you're making the right choice for your applications goals.
Windows Azure Web Sites
You have properly identified that Windows Azure Web Sites is a great starting point for an application, however you could also consider that Web Sites does offer enough scalability for many solutions.
Pros
10 Free sites during preview [Free for 12 months]
Easy Deployment (use Git, TFS, Web Deploy or FTP)
Quick Scalability (You can move to your own dedicated cluster [aka reserved standard])
Simple Development (Supports Classic ASP, ASP.NET, Node.js, Python & PHP)
Persistent Environment (most people are used to this)
Cons
No SSL Support on Custom Domains
in Preview (currently no SLA)
Windows Azure Cloud Services
Cloud Services (formerly known as Hosted Services) is definitely the vision for the future of Web Applications. It is built with resiliency in mind to keep the cost of applications affordable by scaling to meet demand, and dial back capacity when your traffic slows.
Pros
Increased control over the cost of your application (if architected correctly)
Flexibility (You have full control over the environment)
SSL Support
Language Agnostic
Web Server Agnostic (although IIS is available by default)
Auto Management of Servers
Cons
Architecture should be carefully considered
Deployment time is slower (Slows development cycle)
Things to consider for Portability
The items above might have given you enough to plan the immediate future of the application and it is very likely that you might want to consider Cloud Services in the future (it fits a number of application scenarios better in the long run).
Here is a list of things to help portability between Web Sites to Cloud Services:
Start thinking Stateless
Windows Azure Web Sites is nice as it is a persistent environment, which means you are able to store things like session state and assets to the disk.
Although this is a good feature, it's best to start planning towards a stateless application, if your end goal is to be in Cloud Services. Here are a few things you can do to start thinking stateless:
Don't rely on Session State
If you need it, come up with a strategy to make it scale (Caching Service, SQL, or Storage)
Use the Storage Service
Assets such as Static HTML, css, javascript and images are better placed in Storage
Avoids additional bandwidth on your Web Site (potentially stay shared longer for lower cost)
Can be CDN Enabled, provides a better experience for International markets
Easier to update web assets when application is migrated to Cloud Services
Storing User content
If your application already stores to the Storage Service, there is one less code modification in the future when moving to cloud services.
Make it easy to discover patterns in your Data
The benefit of Cloud Services is it enables you to reduce cost by only scaling what needs scaled. Starting the process of identifying your scale units i.e. How you partition your database or Tables in Storage.
I read all post and all of them are very helpful.
In addition to all post , I found an info on msdn : Windows Azure Websites, Cloud Services, and VMs: When to use which?
With Windows Azure Websites you can:
Build highly scalable web sites on Windows Azure.
Quickly and easily deploy sites to a highly scalable cloud environment that allows you to start small and scale as needed.
Use the languages and open source applications of your choice then deploy with FTP, Git or TFS, and easily integrate Windows Azure services like SQL Database, Caching, CDN and Storage.
With Cloud Services you can:
Build or extend your enterprise applications on Windows Azure.
Create highly-available, scalable applications and services using a rich PaaS environment. Support advanced multi-tier scenarios, automated deployments and elastic scale. Deliver great SaaS solutions to customers anywhere around the world.
And also there is summarizes the option on msdn :
And comparing some features Web Sites and Cloud Services on msdn:
Azure is a great place to have your app, but there are some considerations you need to know before start migrating it.
Azure Websites and Hosted Services are really trivial to deploy. With
Visual studio you generate the package and simply upload it. Then you
have a Development environment to check it. If it's ok for you, swap
ips. If it's not ok for you, upgrade again.
Your instances have some properties that could be annoying. For
example, you cannot be sure about your IP. Then if your app works
with some provider using IP restriction, you will need to figure out
how to proceed.
More considerations. Your "server" could be reimaged at any moment.
If you store something on the local disc, that file could go away at any moment.
Azure works very nice if you have at least 2 instances or more for
each website. Maybe your app is not prepared for that. The first step
will be managing the sessions with the appFabric. Is really
easy, just a change on your web config. Be careful because this
session state doesn't work exactly as the "old one". You cannot store
non-serializable objects (should be easy to adapt) or a very large objects (more than 8MB).
If you are going to develop something from zero, I suggest you to start into azure from the beginning. The reason is simple: it's really cheap to start and you will not pay serious money until the app have lot's of visits. It's also very cheap to setup a SQLAzure and a storage account. One you have all in place, it's easy to add more instances or scale up.
Example:
Imagine you have an idea and you wish to show up to some possible investors.
You start setting up a little SQLAzure database (1GB ), $9,99 monthly.
Then you build a site and you put 2 extra small instances, $18,72 monthly.
Let's say you need 100 GB of space (images, backups, ...), $12,50 monthly.
At his point, you have all in place to start your business paying less than $50 monthly.
If you site have exit and the visits starts to come, you change your instances for small instances (it's really dangerous to have production environment with extra small instances, because do not have cpu reservation). Then you change the extra small cost ($18,71) up to $57,60. Maybe you need more space to that SQL Azure? etc...
prices calculated from here: http://www.windowsazure.com/en-us/pricing/calculator/?scenario=web .
Those are few tips, there is a lot more. My advice is to start a trial account and play with it.
Final advice: Its very easy to solve everything just purchasing more resources. Sometimes you need to refactor and optimize your code. If you simply add more resources each time you have a problem, you could end with a huge bill and a very messy code.
Hope it helps!
Another advantage of Windows Azure Cloud Services over Web Sites is that a cloud service can be added to an Azure Virtual Network. This can give it access to on-premises resources like databases. So if your requirements are such that you need the scalability offered by Azure but need to keep your data on-premises due to security restrictions, cloud services is a better choice.
Azure web sites cannot be part of an Azure virtual network. To access on-premises resources mechanisms such as Azure Service Bus Relay must be configured.
We've had our web site running on PHP on some hosting and at some point decided to move it to Azure (where sits main part of our service). We've started with Azure Web Sites which was great from development point of view (mainly integration with git). But after about a week of testing (when we've decided to actually move the production web site) we've found that currently
No SSL for custom domains
Custom domains are available only for reserved instances (no shared infrastructure)
SLA
So we moved to Hosted Service. The main problem for us was lack of ability of simple deployment (need to build package and upload whole package of the web site), and found solution was to use dropbox - as a startup task for role, we're installing dropbox service on the machine, which takes all the web site from dropbox, which in turn have SVN checked out folder, so site updates became very easy.

What exactly is Heroku?

I just started learning Ruby on rails and I was wondering what Heroku really is? I know that its a cloud that helps us to avoid using servers? When do we actually use it?
Heroku is a cloud platform as a service. That means you do not have to worry about infrastructure; you just focus on your application.
In addition to what Jonny said, there are a few features of Heroku:
Instant Deployment with Git push - build of your application is performed by Heroku using your build scripts
Plenty of Add-on resources (applications, databases etc.)
Processes scaling - independent scaling for each component of your app without affecting functionality and performance
Isolation - each process (aka dyno) is completely isolated from each other
Full Logging and Visibility - easy access to all logging output from every component of your app and each process (dyno)
Heroku provides very well written tutorial which allows you to start in minutes. Also they provide first 750 computation hours free of charge which means you can have one processes (aka Dyno) at no cost. Also performance is very good e.g. simple web application written in node.js can handle around 60 - 70 requests per second.
Heroku competitors are:
OpenShift by Red Hat
Windows Azure
Amazon Web Services
Google App Engine
VMware
HP Cloud Services
Force.com
It's a cloud-based, scalable server solution that allows you to easily manage the deployment of your Rails (or other) applications provided you subscribe to a number of conventions (e.g. Postgres as the database, no writing to the filesystem).
Thus you can easily scale as your application grows by bettering your database and increasing the number of dynos (Rails instances) and workers.
It doesn't help you avoid using servers, you will need some understanding of server management to effectively debug problems with your platform/app combination. However, while it is comparatively expensive (i.e. per instance when compared to renting a slice on Slicehost or something), there is a free account and it's a rough trade off between whether it's more cost effective to pay someone to build your own solution or take the extra expense.
Heroku Basically provides with webspace to upload your app
If you are uploading a Rails app then you can follow this tutorial
https://github.com/mrkushjain/herokuapp
As I see it, it is a scalable administrated web hosting service, ready to grow in any sense so you don't have to worry about it.
It's not useful for a normal PHP web application, because there are plenty of web hosting services with ftp over there for a simple web without scalability needs, but if you need something bigger Heroku or something similar is what you need.
It is exposed as a service via a command line tool so you can write scripts to automate your deployments. Anyway it is pretty similar to other web hosting services with Git enabled, but Heroku makes it simpler.
That's its thing, to make the administration stuff simpler to you, so it saves you time. But I'm not sure, as I'm just starting with it!
A nice introduction of how it works in the official documentation is:
https://devcenter.heroku.com/articles/how-heroku-works
Per DZone: https://dzone.com/articles/heroku-or-amazon-web-services-which-is-best-for-your-startup
Heroku is a Platform as a Service (PaaS) product based on AWS, and is vastly different from Elastic Compute Cloud. It’s very important to differentiate ‘Infrastructure as a Service’ and ‘Platform as a Service’ solutions as we consider deploying and supporting our application using these two solutions.
Heroku is way simpler to use than AWS Elastic Compute Cloud. Perhaps it’s even too simple. But there’s a good reason for this simplicity. The Heroku platform equips us with a ready runtime environment and application servers. Plus, we benefit from seamless integration with various development instruments, a pre-installed operating system, and redundant servers.
Therefore, with Heroku, we don’t need to think about infrastructure management, unlike with AWS EC2. We only need to choose a subscription plan and change our plan when necessary.
That article does a good job explaining the differences between Heroku and AWS but it looks like you can choose other iaas (infrastructure) providers other than AWS. So ultimately Heroku seems to just simplify the process of using a cloud provider but at a cost.

What is the best solution for real-time bi-directional communication between a web application running on a mobile phone and a server?

I'm looking at having thousands of simultaneous connections from mobile phones to the server whereby anytime a user interacts with his cell phone, the data is sent and logged by the server. Also, anytime the server has new information for that user, the server can push that information without a browser refresh. I am wondering what is more stable and how you would build this?
A good real-time framework or infrastructure will have numerous APIs that should let you connect any device, no matter the technology, to the real-time server e.g. an iOS client library for iPhone and iPad, a JavaScript client library for numerous platforms including normal and mobile web, an Android compatible Java library and so on.
An interesting idea might be to choose which ever framework or real-time service suits your needs best and then using something like PhoneGap. But, as #rt2088 says, it depends if you need the notification app to be running as a service on the phone or as a standalone application.
The choice will also depend on whether you want to install, host, maintain and manage the scaling of your own real-time services or not. If not, there are a number of services out there who you could use so you can concentrate on building your application. If you do want to manage your own infrastructure then the Comet Maturity guide could be a good start. It's a little out of date but is still probably the best reference available.
the ability to push new content the
user based on his GPS location which
is "pinged" to our server. Based on
that, we deliver local content. What
frameworks are you talking about?
There are a number of real-time frameworks available at the moment. Some are hosted services and others require installation on your own hardware. The majority of them will come with a bunch of libraries in different technologies that make it easier to get up and running with them e.g. a JavaScript library that wraps the WebSocket object and also manages fallback for web browsers that don't support WebSockets.
I've just created a Real-Time Technologies Guide in which I've listed all the real-time technologies that I could think of and provided a bunch of tags associated with each.
wouldn't a javascript client library
cover all platforms if it is a web
appilcation?
If the application is a web application then yes, a JavaScript library would be all you need for the client application. The server side libraries that you require would depend on the real-time technology you choose.
Best solution to achieve this is to use the WebSocket communication. It is bidirectional asynchronous communication. Currently every browser supports this new standard and plenty of code snippets available. You just have to google it. There are many server and client side frameworks. choose the one best suits to your requirement.
The details of the WebSocket specification is available at -
Websocket specification
Do you need notification when user uses mobile browser of handset or the mobile handset itself (performing non-browser tasks)? Based on that, the framework to record user activity can be selected.

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