NOTE: This project is no longer maintained. You might want to look at sbt-web which has a closure complier.

sbt-closure

Simple Build Tool plugin for compiling JavaScript files from multiple sources using Google's Closure Compiler.

Settings

Installation

If you have not already added the sbt community plugin resolver to your plugin definition file, add this

resolvers += Resolver.url("sbt-plugin-releases",
  new URL("http://scalasbt.artifactoryonline.com/scalasbt/sbt-plugin-releases/"))(
    Resolver.ivyStylePatterns)

Then add this (see ls.implicit.ly for current version)

addSbtPlugin("org.scala-sbt" % "sbt-closure" % "0.1.0")

Then in your build definition, add

seq(closureSettings:_*)

This will append sbt-closure's settings for the Compile and Test configurations.

To add them to other configurations, use the provided closureSettingsIn(config) method.

seq(closureSettingsIn(SomeOtherConfig):_*)

Usage

The plugin scans your src/main/javascript directory and looks for files of extension .jsm. These files should contain ordered lists of JavaScript source locations. For example:

# You can specify remote files using URLs...
http://code.jquery.com/jquery-1.5.1.js

# ...and local files using regular paths
#    (relative to the location of the manifest):
lib/foo.js
bar.js
../bar.js

# Blank lines and bash-style comments are ignored.

The plugin compiles this in two phases: first, it downloads and caches any remote scripts. Second, it feeds all of the specified scripts into the Closure compiler. The compiler outputs a file with the same name but with a .js extension under path/to/resource_managed/main/js

For example, if your manifest file is at src/main/javascript/foo.jsm in the source tree, the final path would be resource_managed/main/js/foo.js in the target tree.

If, on compilation, the plugin finds remote scripts already cached on your filesystem, it won't try to download them again. Running sbt clean will delete the cache.

Tasks

The plugin is tied to the compile task and will run whenver compile is run. You can also run closure to run it on its own. clean(for closure) will delete the generated files.

Customization

If you're using xsbt-web-plugin, add the output files to the webapp with:

// add managed resources to the webapp
(webappResources in Compile) <+= (resourceManaged in Compile)

Changing the directory that is scanned, use:

(sourceDirectory in (Compile, ClosureKeys.closure)) <<= (sourceDirectory in Compile)(_ / "path" / "to" / "jsmfiles")

Changing target js destination:

To change the default location of compiled js files, add the following to your build definition

(resourceManaged in (Compile, ClosureKeys.closure)) <<= (resourceManaged in Compile)(_ / "your_preference" / "js")

File versioning

The plugin has a setting for a file suffix that is appended to the output file name before the file extension. This allows you to update the version whenever you make changes to your Javascript files. Useful when you are caching your js files in production. To use, add the following to your build.sbt:

(ClosureKeys.suffix in (Compile, ClosureKeys.closure)) := "4"

Then if you have manifest file src/main/javascript/script.jsm it will be output as resource_managed/src/main/js/script-4.js

This is only half of the puzzle, though. In order to know what that suffix is in your code, you can use the sbt-buildinfo plugin. Add the plugin to your project, then add the following to your build.sbt:

seq(buildInfoSettings: _*)

buildInfoPackage := "mypackage"

buildInfoKeys := Seq[Scoped](ClosureKeys.suffix in (Compile, ClosureKeys.closure))

sourceGenerators in Compile <+= buildInfo

This will generate a Scala file with your suffix in src_managed/main/BuildInfo.scala and you can access it in your code like this:

mypackage.BuildInfo.closure_suffix

In my Lift project I have the following snippet:

package mypackage
package snippet

import net.liftweb._
import util.Helpers._

object JavaScript {
  def render = "* [src]" #> "/js/script-%s.js".format(BuildInfo.closure_suffix)
}

Which is called in my template like:

<script lift="JavaScript"></script>

Acknowledgements

This plugin is a sbt 0.11.2 port of sbt-closure

It was modeled after and heavily influenced by less-sbt