Cloud9 and Ceylon

Cloud9

I recently stumbled across a really impressive online full fledged coding IDE called Cloud9. By signing up for a free account you get as many public workspaces as you want, plus, a quite complete Linux environment including a really outstanding terminal. This is all made in javascript and HTML5, so this is 100% portable. A recent browser is all you need.

Cloud9 proposes workspace templates, which includes node.js, ruby on rails, php, pyhon and some others. Me being on the Java side, I initially thought it was missing this behemoth, but found out that the JDK comes pre-installed, along with a few tools like Ant.

I find there is no better environment for prototyping some stuff. Nothing to install.

I might write a complete article on Cloud9 in the near future.

Ceylon

I'm a big fan of Gavin King, all the way since the beginning of Hibernate a long time ago. I was quite curious when I heard he was on a special project at Red Hat which was about creating a new language for the JVM. Now that version 1.0.0 is out, it's time to put our hands dirty and check this out. 

Installing Ceylon on Cloud9

From here I assume you already have your Cloud9 account and you created a custom workspace.

Prerequisites for Ceylon are a JDK plus Ant, and they come preinstalled in Cloud9. So lets download the package and install it at convenient place (don't forget to add Ceylon binaries to the $PATH variable in ~/.bashrc):

	mkdir ~/packages
	wget http://downloads.ceylon-lang.org/cli/ceylon-1.0.0.zip
	mkdir ~/apps
	unzip ~/packages/ceylon-1.0.0.zip -d ~/apps

view raw gistfile1.sh hosted with ❤ by GitHub

We now have a working Ceylon installation.

Creating the Hello World project

	# Optional, but I like to create a symbolic name so the worspace is more readable
	cd ~
	ln -s 885674 ceylon-demo
	cd ceylon-demo
	ceylon new helloworld .
	Enter module name [com.example.helloworld]: com.example.helloworld
	Enter module version [1.0.0]:
	Would you like to generate Eclipse project files? (y/n): n
	Would you like to generate an ant build.xml? (y/n): y

view raw ceylon-project-creation hosted with ❤ by GitHub

Executing the project

First execution will provoke the following exception:

	mathieufortin01@ceylon-demo:~/ceylon-demo $ ant run
	Buildfile: build.xml
	ceylon-ant-taskdefs:
	compile:
	BUILD FAILED
	...
	Caused by: java.lang.IllegalArgumentException: Cannot create Ceylon cache repository directory: /var/lib/openshift/5398cc545004464a170006ee/.ceylon/cache
	at com.redhat.ceylon.cmr.impl.RootRepositoryManager.<init>(RootRepositoryManager.java:56)
	at com.redhat.ceylon.cmr.impl.RootRepositoryManager.<init>(RootRepositoryManager.java:50)
	at com.redhat.ceylon.cmr.impl.RepositoryManagerBuilderImpl.<init>(RepositoryManagerBuilderImpl.java:45)
	... 33 more

view raw ceylon-first-exec hosted with ❤ by GitHub

This is a common error on Cloud9 when installing/running custom binaries. Access controls restrict write operations in core folders.
We need to override where the cache folder will reside:

	# create cache folder
	mkdir ~/.ceylon
	mkdir ~/.ceylon/cache
	# create configuration file
	vi ~/ceylon/config
	# set cache folder in newly create cache folder in home directory. To find home, use echo $HOME.
	# and save the file

view raw gistfile1.sh hosted with ❤ by GitHub

A new execution will give us a new error:

	mathieufortin01@ceylon-demo:~/ceylon-demo $ ant compile
	Buildfile: build.xml
	ceylon-ant-taskdefs:
	compile:
	[ceylon-compile] /var/lib/stickshift/5398cc545004464a170006ee/app-root/data/886846/source/com/example/helloworld/run.ceylon:1: error: compiler message file broken: key=compiler.err.ceylon.parser arguments=incorrect syntax: no viable alternative at token '"The classic Hello World program"', {1}, {2}, {3}, {4}, {5}, {6}, {7}
	[ceylon-compile] doc "The classic Hello World program"
	[ceylon-compile] ^
	[ceylon-compile] /var/lib/stickshift/5398cc545004464a170006ee/app-root/data/886846/source/com/example/helloworld/run.ceylon:6: error: compiler message file broken: key=compiler.err.ceylon.parser arguments=incorrect syntax: no viable alternative at token '"Run the module `com.example.helloworld`."', {1}, {2}, {3}, {4}, {5}, {6}, {7}
	[ceylon-compile] doc "Run the module `com.example.helloworld`."
	[ceylon-compile] ^
	[ceylon-compile] ceylon compile: There were 2 errors
	BUILD FAILED
	/var/lib/stickshift/5398cc545004464a170006ee/app-root/data/886846/build.xml:22: Error running Ceylon compile tool (an exception was thrown, run ant with -v parameter to see the exception)

view raw gistfile1.sh hosted with ❤ by GitHub

It appears that commenting out the documentation lines in run.ceylon fixes the problem.

	mathieufortin01@ceylon-demo:~/886846 $ ant run
	Buildfile: build.xml
	ceylon-ant-taskdefs:
	compile:
	[ceylon-compile] No need to compile com.example.helloworld/1.0.0, it is up to date
	[ceylon-compile] Everything is up to date
	run:
	[ceylon-run] Hello, World!
	BUILD SUCCESSFUL
	Total time: 14 seconds

view raw gistfile1.sh hosted with ❤ by GitHub

Next steps

This is just the beginning. Full Ceylon applications can probably be build this way. By natively linking to GitHub, Cloud9 makes a wonderful environment to prototype and test ideas.