writing nodejs applications in kotlin with intellij idea ce - node.js

Question

I am trying to develop a Nodejs application using Kotlin 1.3.11 using the IntelliJ IDEA CE development environment. Unfortunately I haven't made any progress towards a running application. To ensure everything is setup correctly I want to print out a simple "hello world".
I searched for articles or tutorials about the topic but I didn't find much about bringing those three together (Kotlin, IntelliJ, Nodejs). The most specific ones which I found are:
a medium post and another post.
As far as I (believe to) know, there are three major steps:
calling initializing the node app via npm and using npm to install the node dependencies like kotlin and expressjs
creating a build.gradle to define other dependencies and tasks
creating an IntelliJ IDEA project
I tried to perform the steps in different orders but I never came to a running application. Also I searched in IntelliJ's documentation but the Nodejs integration isn't a feature of the free community edition. There isn't a description how to make Kotlin and Nodejs work together too.
Has anyone here successfully tried to do that (or failed and knows why it is not going to work)? Do I have to use another IDE or to write my own build tools/toolchain?
Sincerely J.

Answer 1

I haven't done this in IDEA CE, but theoretically, this should work.
Prerequisites: You have node installed, you can execute gradle tasks
This is a Minimum Configuration, There is a comprehensive one. Add a comment if intrested for that
Step 1:Create a new Kotlin/JS project (with gradle) and make sure that your gradle build file looks like this
group 'node-example'
version '1.0-SNAPSHOT'
buildscript {
ext.kotlin_version = '1.3.11'
repositories {
mavenCentral()
}
dependencies {
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
}
}
apply plugin: 'kotlin2js'
repositories {
mavenCentral()
}
dependencies {
compile "org.jetbrains.kotlin:kotlin-stdlib-js:$kotlin_version"
}
compileKotlin2Js.kotlinOptions {
moduleKind = "commonjs"
outputFile = "node/index.js"
}
task npmInit(type: Exec) {
commandLine "npm", "init", "-y"
}
task npmInstall(type: Exec) {
commandLine "npm", "install", "kotlin", "express", "--save"
}
task npmRun(type: Exec) {
commandLine "node", "node/index.js"
}
npmRun.dependsOn(build)
Step 2: After syncing your build.gradle in step 1 run the gradle tasks npmInit and npmInstall
./gradlew :npmInit
./graldew :npmInstall
Step 3:
Create your kotlin file (index.kt/main.kt/whatever.kt) in src/main/kotlin and test the code below
external fun require(module:String):dynamic
fun main(args: Array<String>) {
println("Hello JavaScript!")
val express = require("express")
val app = express()
app.get("/", { req, res ->
res.type("text/plain")
res.send("Kotlin/JS is kool")
})
app.listen(3000, {
println("Listening on port 3000")
})
}
Step 4: RTFA - Run The App
Run the gradle task npmRun
./gradlew :npmRun
Hope that helps
Note:
1. This template was pulled from the medium post you asked above and modified a little
2. Remember to run your gradle tasks using sudo (if you are using linux)

Answer 2

Edit: Alternatively, you could clone https://github.com/miquelbeltran/kotlin-node.js and follow the instructions in the read me.
I managed to get the Medium post to work by replacing gradle build with the following (since the post was published in 2017(!) and requires a much older version of Gradle):
Comment out the entire contents of build.gradle like so:
/*group 'node-example'
...
compileKotlin2Js.kotlinOptions {
moduleKind = "commonjs"
outputFile = "node/index.js"
}*/
Run this command in the command prompt: (3.4.1 was the latest version of Gradle just before the Medium post was published.)
gradle wrapper --gradle-version=3.4.1
Uncomment out build.gradle:
group 'node-example'
...
compileKotlin2Js.kotlinOptions {
moduleKind = "commonjs"
outputFile = "node/index.js"
}
Run this command in place of gradle build:
gradlew build
And finally run this command as in the post: (As of writing this answer on StackOverflow, Node.js does not be downgraded and the current LTS version 10.16.0 works perfectly.)
node node/index.js