Awesome
Scala.js Scripts
Small library which provides a way to link Scala.js output to HTML templating engines, such as twirl, scalatags or even standard scala string interpolation.
Setup
Add the library to build.sbt
:
libraryDependencies += "com.vmunier" %% "scalajs-scripts" % "1.3.0"
Integration with Twirl
Available Twirl Templates
There are four Twirl templates: scripts.scala.html
, selectScript.scala.html
, jsdeps.scala.html
, launcher.scala.html
.
scripts.scala.html
is the main template, it includes the three other templates.selectScript.scala.html
selects the full-optimized javascript file (-opt.js
) if it exists, selects the fast-optimized javascript file (-fastopt.js
) otherwise.jsdeps.scala.html
includes the javascript dependencies if they exist.launcher.scala.html
includes the Scala.js launcher if it exists.
Usage
The templates have the same parameters, and can be called similarly. The parameters are described below:
@(projectName: String,
assets: String => String,
resourceExists: String => Boolean
)
projectName
, name of the Scala.js project, which is used to compute the Scala.js file names, projectName-fastopt.js, projectName-launcher.js, etc.assets
, function, which given a Scala.js file name, returns the HTTP route from which the file can be fetched.resourceExists
, function, which given a Scala.js file name, returns true when the resource exists, false otherwise.
Generic usage for any HTTP-based application (e.g. Akka HTTP, Spray):
@scalajs.html.scripts(
projectName = "client",
name => s"/assets/$name",
name => getClass.getResource(s"/public/$name") != null)
Usage for the Play Framework specifically:
@scalajs.html.scripts(
"client",
name => routes.Assets.at(name).toString,
name => getClass.getResource(s"/public/$name") != null)
Usage for the Play Framework with fingerprinting for public assets:
@scalajs.html.scripts(
"client",
name => routes.Assets.versioned(name).toString,
name => getClass.getResource(s"/public/$name") != null)
Additional HTML attributes can be added to the generated <script>
tags:
@scalajs.html.scripts(
projectName = "client",
name => s"/assets/$name",
name => getClass.getResource(s"/public/$name") != null,
Html("""charset="UTF-8" defer""")
)
Note:
The Twirl templates require a resourceExists
function because the application classpath may not be accessible from the library.
Play for instance, puts libraries in a parent classpath of the application, meaning they can't see the classes provided by the application.
Since the classloaders are split, libraries can never make any assumptions about their classloader with regards to the applications classloader.
More info about Play classloader can be found in this issue.
Integration with ScalaTags
Integration with ScalaTags is as simple as calling one of the scalajs-scripts function inside a tag.
Here is a template showing how to use scalajs.html.scripts
to render a basic index.html:
import scalatags.Text._
import scalatags.Text.all._
object Application {
def index(title: String): TypedTag[String] = {
scalatags.Text.tags.html(
head(
scalatags.Text.tags2.title(title)
),
body(
raw(scalajs.html
.scripts("client", name => s"/assets/$name", name => getClass.getResource(s"/public/$name") != null)
.body)
)
)
}
}
The raw
function in ScalaTags allows you to embed raw HTML in the tag and calling .body
on the scripts
method outputs the raw html.
Publish a new version of the library
New versions are automatically published to Sonatype when creating a git tag, thanks to sbt-ci-release.