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kotlinlang

Hey guys, been looking how to make a fat jar from kotlin, was looking at <https://stackoverflow.com/questions/41794914/how-to-create-a-fat-jar-with-gradle-kotlin-script|this> although its not working (im using gradle 7+) any suggestions?

I’ve been using Shadow for a few years to do this. Ktor docs also suggests using shadow. <https://ktor.io/docs/fatjar.html>

ya Ive tried that but somehow it didn’t work

Yes, check <https://github.com/johnrengelman/shadow|shadow plugin>

when I run the jar produced by shadowJar it says mainclass not found :stuck_out_tongue:

my build.gradle lookis like this
```plugins {
    id 'application'
    id 'kotlin'
    id 'io.gatling.gradle'
    id 'com.github.johnrengelman.shadow'
}

application {
    mainClass = 'io.gatling.app.Gatling'
}

shadowJar {
    manifest {
        attributes 'Main-Class': 'io.gatling.app.Gatling'
    }
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlinVersion"
}```

If Gatling is a file with a main function on file-level (e.g. no class), try `io.gatling.app.GatlingKt`

im using gatling plugin as it is described <https://gatling.io/docs/gatling/reference/current/extensions/gradle_plugin/|here>

Without shadow I was trying this way
```plugins {
    id 'application'
    id 'kotlin'
    id 'io.gatling.gradle'
}

task fatJar(type: Jar) {
    manifest {
        attributes 'Main-Class': 'io.gatling.app.Gatling'
    }
    from { configurations.implementation.collect { it.isDirectory() ? it : zipTree(it) } }
    with jar
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlinVersion"
}```
But i get this error
```Resolving dependency configuration 'implementation' is not allowed as it is defined as 'canBeResolved=false'.
  Instead, a resolvable ('canBeResolved=true') dependency configuration that extends 'implementation' should be resolved.```

I suspect it is due to how the gatling plugin gets the dependencies

My recommendation would be to *not* buid a fat jar actually.
Fat jars basically only have drawbacks and with Gradle it is super easy to build a proper distribution including a start script you can simply call to execute your project. You are even already applying and configuring the `application` plugin, you just have to use the `distZip` or `distTar` result and you are good to go.
See <https://fatjar.net> for various quotes.

it looks like Gatling sets up a separate source set and run configuration, not main, so it's expected that io.gatling.app.Gatling isn't in the main jar or its dependencies