sbt-typescript

Typescript 🤝 Scala

This sbt plugin compiles the TypeScript code in your Play application to javascript fit for consumption by your average browser and device.

Setup

For Play 2.9+ projects, add the following line to your project/plugins.sbt:

addSbtPlugin("com.github.platypii" % "sbt-typescript" % "5.3.2")

For Play 2.8- projects, use the previous version 4.6.4.

If your project is not a Play application you will have to enable sbt-web in build.sbt:

lazy val root = (project in file(".")).enablePlugins(SbtWeb)

It is STRONGLY RECOMMENDED that you have node installed. It is possible to fallback to JVM-based trireme, but it is slow, and may not work with the latest javascript code.

Dependencies

NPM libraries are used as standard sbt dependencies (jar files). Add your typescript libraries as dependencies as follows. If the library doesn't include typescript definitions add them too.

resolvers += Resolver.bintrayRepo("webjars","maven")
libraryDependencies ++= Seq(
    "org.webjars.npm" % "react" % "15.4.0",
    "org.webjars.npm" % "types__react" % "15.0.34"
)

These NPM dependencies are resolved through WebJars. Check whether the versions of the NPM packages you need are available there. If not, you can add webjars to maven through the webjars.org website. Since we added the webjars resolver they will be available immediately. Otherwise, you would have to wait before being able to use them. NPM package names like @angular/code and @types/react are a bit different in webjars: angular__react and types__react. Add the following to build.sbt to resolve against those npms.

resolveFromWebjarsNodeModulesDir := true

To lint your TypeScript code add sbt-tslint to your project and create a tslint.json file with the linting rules.

Configuration

Create a tsconfig.json file in the root of your project with the required compiler options.

The following tsc compiler options are managed by sbt-typescript so setting them in tsconfig.json has no effect: outDir, rootDirs, paths, baseUrl, typeRoots. If you use the stage compile mode the outFile option is also managed by sbt-typescript.

Option	Description
outFile	Concatenate and emit output to a single file.
outDir	Destination directory for output files.
typingsFile	A file that refers to typings that the build needs. Default None, but would normally be "/typings/index.d.ts"

To be able to view the original Typescript code from your browser when developing add the following to tsconfig.json

"compilerOptions": {
    "sourceMap": true,
    "mapRoot": "/assets",
    "sourceRoot": "/assets",

You can get more verbose logging of what sbt-typescript is doing by adding to build.sbt:

typescript / logLevel := Level.Debug

Testing

To test your TypeScript code add an sbt plugin for a JS test framework. For instance sbt-jasmine or sbt-mocha. You can override tsc configurations for your test code. To do that create a file tsconfig.test.json and add to build.sbt

(typescript / projectTestFile) := Some("tsconfig.test.json")

Any settings in that file will override those in tsconfig.json for the compilation of test code.

Configuring an IDE

The typescript version of your project can be found in project/target/node-modules/webjars/typescript. Configure your IDE to use that and point it to the tsconfig.json.

Compiling directly through tsc

Sometimes it can be helpful to compile your project directly through the TypeScript compiler without sbt-typescript in between to check whether a problem is an sbt-typescript problem. To do that you can run

project/target/node-modules/webjars/typescript/bin/tsc -p . -w

Make sure to set the executable bit if necessary. For this kind of compilation to work you have to fill in the settings in tsconfig.json that sbt-typescript normally manages. See the Angular2 demo project for an example.

Compiling to a single js file

You can develop using individual javascript files when running sbt ~run in Play and have your whole typescript application concatenated into a single javascript output file for your stage environment without changes to your sources. To do that you have to add a -DtsCompileMode=stage parameter to the sbt task in your CI that creates the stage app. So for Play that will often be sbt stage -DtsCompileMode=stage.

Import modules without type information

If you are importing modules for which you don't have the typings you can ignore the TS2307 can not find module error:

tsCodesToIgnore := List(canNotFindModule)

Publishing sbt-typescript

Use sbt-sonatype plugin.

sbt publishSigned
sbt sonatypeBundleRelease

History

This project was started by Brandon Arp: https://github.com/ArpNetworking/sbt-typescript

With further contributions by Joost de Vries: https://github.com/joost-de-vries/sbt-typescript

Adopted by platypii: https://github.com/platypii/sbt-typescript