I'm a Ruby developer, but I like Scala very much as well.
For Rails framework we have awesome tools that supports deployments like Capistrano automation tool and Puma/Unicorn servers. With simple cookbooks using Chef or Ansible I can easily setup my VPS and deploy Rails application there.
How does automatic deployment look like in Play framework? What is minimal required stack for developing and deploying Play applications? Are there any tools for automatic deployment? What are recommended application servers?
All you need to run a Play app is a JVM. Play is container-less. So deploying your Play app in production is as simple as running a script that invokes a fat jar with all the other required jars in the classpath.
$play dist should generate a zip file that contains everything you need to run the app.
You can use Ansbile to automate.
http://code.hootsuite.com/automating-our-scala-deploys-with-ansible-case-study/
http://www.ansible.com/press-release/ansibleworks-typesafe
To deploy Play Framework apps in AWS (Amazon) ec2 using Ansible playbook
As well as Chef.
https://github.com/gildegoma/chef-typesafe-stack
If you are happy to run on AWS, Boxfuse comes with native Play 2 support.
You can now simply execute boxfuse run my-play-app-1.0.zip -env=prod and this will automatically:
create a minimal AMI tailor-made for your Play 2 app
create an elastic IP
create a security group with the correct permissions
launch an instance of your app
All future updates are performed as blue/green deployments with zero downtime.
This also works with Elastic Load Balancers and Auto-Scaling Groups and the Boxfuse free tier is designed to fit the AWS free tier.
You can read more about it here: https://boxfuse.com/blog/playframework-aws
Disclaimer: I'm the founder and CEO of Boxfuse
I have developed a Scala/Play webapp and now I am trying to deploy it on production.
What is the recommended "best way" of doing that?
The documentation mentions only runnig it from play console, which does not seem very robust (in case of machine restarts etc).
There are apporaches to wrap the app into a war file and deploy on Tomcat7 (e.g. play2war), but they do not seem to be actively developed (e.g. there is only beta support for 2.3, the plugin is not available from maven repo etc).
What is the right way of doing this?
If you host the application on Windows then take a look at Yet Another Java Service Wrapper which wraps the application in a Windows service that will keep it running, even after restarts.
If you run it on Linux then take a look at Supervisord and Monit, which monitors the application and starts, restarts and stops it when needed.
See the following links for tutorials:
How do I run a Play Framework 2.0 application as a Windows service?
http://marcovanduijn.blogspot.nl/2011/08/run-play-framework-application-as.html
http://blog.fgribreau.com/2013/09/how-to-make-play-framework-2-work-with.html
I am to deploy a scala project on AWS. Many a sites are talking about "Play instances". So, I am little confused. What it is exactly and how it is helpful in successful deployment.
Play is a framework which makes it easy to develop web applications in Java or Scala. It is unrelated to AWS. Play allows you to develop test and debug locally. When you want to deploy your Play application to AWS, a very straightforward way (though not the only way) is to use the play war command to generate a WAR file of your application, then use Elastic Beanstalk to deploy it to AWS EC2 instances running Tomcat.
More information about Elastic Beanstalk is here: http://aws.amazon.com/elasticbeanstalk/
I am guessing what people are calling a "Play instance" is a Play application running on an EC2 instance.
I will try to make it simplify. I am using windows azure cloud to host our web services and databases. and these web services are accessible via URL: "https://server.mydomain.com"
now we made a few major changes to our model and hence web services as a whole. This breaks the API interface for older users. Now we want to deploy the latest version on URL: "https://server.mydomain.com/v2" so that old users can still access the older version.
I searched around SO and other resources but i couldnt find a definite answer how to deploy new version without messing up the old version.
Anything in right direction will be helpful.
In one of the projects I was working on, we built in a versioning scheme on top of our Web API. We used this tutorial to get started. I would recommend starting there.
Sorry for the generic answer, if you post some more specifics I will make some updates.
I'd suggest to deploy separate cloud service and use "v2.server.mydomain.com"
I love Heroku but I would prefer to develop in Scala rather than Ruby on Rails.
Does anyone know of any services like Heroku that work with Scala?
UPDATE: Heroku now officially supports Scala - see answers below for links
As of October 3rd 2011, Heroku officially supports Scala, Akka and sbt.
http://blog.heroku.com/archives/2011/10/3/scala/
Update
Heroku has just announced support for Java.
Update 2
Heroku has just announced support for Scala
Also
Check out Amazon Elastic Beanstalk.
To deploy Java applications using
Elastic Beanstalk, you simply:
Create your application as you
normally would using any editor or IDE
(e.g. Eclipse).
Package your
deployable code into a standard Java
Web Application Archive (WAR file).
Upload your WAR file to Elastic
Beanstalk using the AWS Management
Console, the AWS Toolkit for Eclipse,
the web service APIs, or the Command
Line Tools.
Deploy your application.
Behind the scenes, Elastic Beanstalk
handles the provisioning of a load
balancer and the deployment of your
WAR file to one or more EC2 instances
running the Apache Tomcat application
server.
Within a few minutes you will
be able to access your application at
a customized URL (e.g.
http://myapp.elasticbeanstalk.com/).
Once an application is running,
Elastic Beanstalk provides several
management features such as:
Easily deploy new application versions
to running environments (or rollback
to a previous version).
Access
built-in CloudWatch monitoring metrics
such as average CPU utilization,
request count, and average latency.
Receive e-mail notifications through
Amazon Simple Notification Service
when application health changes or
application servers are added or
removed.
Access Tomcat server log
files without needing to login to the
application servers.
Quickly restart
the application servers on all EC2
instances with a single command.
Another strong contender is Cloud Foundry. One of the nice features of Cloud Foundry is the ability to have a local version of "the cloud" running on your laptop so you can deploy and test offline.
I started working on the exact same thing as what you said a few weeks ago. I use Lift, which is a great framework and has a lot of potential, on top of Linux chroot environment.
I'm done with a demo version, but Linux chroot is not that stable (nor secure), so I'm now switching to FreeBSD jail on Amazon EC2, and hopefully it'll be done soon.
http://lifthub.net/
There are also other Java hosting environment including VMForce mentioned above.
If you are looking for a custom setup which also has the ease of deployment that heroku offers: http://dotcloud.com. They are invite only right now but I was given access in under three days. I am working on a Lift/MongoDB project there and it works well.
Off the top of my head, only VMForce comes to mind, but its not available yet. This will be a Java-oriented service, so that probably means you'll have to spend a wee bit of time figuring out how to package the app.
For more discussion, there was a debate about this in 2008.
I'm not entirely sure if it's really suitable or not, but people have deployed Scala applications to Google App Engine, for example http://mawson.wordpress.com/2009/04/10/first-steps-with-scala-on-google-app-engine/
Actually you can run scala on heroku right now. You don't believe it?
https://github.com/lstoll/heroku-playframework-scala
I'm not sure the tricks lstoll has used are legit but using the
new cedar platform where you can run custom processes and some
ingenious Gemfile hacking he has managed to bootstrap the Java
play platform into a process. Seems to work as he has a live
site running a test page.
Stax cloud service offers preconfigured lift project skeleton. Also, there is a tutorial on how to deploy lift project to appengine.