I am trying to use Shadow Gradle plugin to create a fat jar.
Part of my build.gradle.kts looks like this:
plugins {
application
kotlin("jvm") version "1.6.21"
id("com.github.johnrengelman.shadow") version "7.1.2"
}
group = "com.test"
version = "0.1"
application {
mainClass.set("com.test.ApplicationKt")
}
Everything is good, but I want to include .properties files in the fat jar as well.
tasks {
withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile> { kotlinOptions { jvmTarget = "17" } }
named<com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar>("shadowJar") {
archiveBaseName.set("shadow")
mergeServiceFiles()
manifest { attributes(mapOf("Main-Class" to "com.test.ApplicationKt")) }
// include("*.properties")
}
For some reason uncommenting the include("*.properties") statement above, makes my fat jar empty. I can build it ok with ./gradlew shadowJar but when I try to run the jar with java -jar I get the error Error: Could not find or load main class...
Any idea what I am missing?
specify the main class name inside shadow task
tasks {
named<ShadowJar>("shadowJar") {
archiveBaseName.set("shadow")
mergeServiceFiles()
manifest {
attributes(mapOf("Main-Class" to "main-class-path"))
}
}
}
Related
I want to make a JAR to test and deploy my app but it doesn't work, locally it can't find the main attribute in the manifest file, and in the deployement it starts but i have this error :
java.lang.noclassdeffounderror: kotlinx/coroutines/slf4j/mdccontex
W
hen I do it locally using the artifact Jar I can't find the MainClass of my app, it recommands me all sorts of other modules.
I tried modying my gradle, the manifest, the configuration but really nothing works it's depressing, it looks so easy on some youtube videos but it just doesn't work
what I do to make the JAR
The classes i have access to when i try to select them
Here is my Gradle
import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
plugins {
kotlin("jvm") version "1.5.10"
application
kotlin("plugin.serialization") version "1.6.10"
}
version = "1.0-SNAPSHOT"
repositories {
mavenCentral()
maven(url = "https://jitpack.io")
}
val ktor_version: String by project
dependencies {
// Fix HTML issue on some responses
implementation("org.apache.commons:commons-text:1.10.0")
// Ktor dependencies
implementation("io.ktor:ktor-client-auth:$ktor_version")
implementation("io.ktor:ktor-client-core:$ktor_version")
implementation("io.ktor:ktor-client-cio:$ktor_version")
implementation("io.ktor:ktor-client-resources:$ktor_version")
implementation("io.ktor:ktor-serialization-kotlinx-json:$ktor_version")
implementation("io.ktor:ktor-client-content-negotiation:$ktor_version")
implementation("io.ktor:ktor-client-logging:$ktor_version")
// Logging dependencies
implementation("ch.qos.logback:logback-classic:1.4.0")
implementation(kotlin("stdlib-jdk8"))
// Database
implementation ("mysql:mysql-connector-java:8.0.30")
implementation ("org.ktorm:ktorm-core:3.5.0")
implementation ("org.ktorm:ktorm-support-mysql:3.5.0")
}
application {
mainClass.set("MainKt")
}
val compileKotlin: KotlinCompile by tasks
compileKotlin.kotlinOptions {
jvmTarget = "1.8"
}
val compileTestKotlin: KotlinCompile by tasks
compileTestKotlin.kotlinOptions {
jvmTarget = "1.8"
}
tasks {
jar {
manifest {
attributes["Main-Class"] = application.mainClass
}
duplicatesStrategy = DuplicatesStrategy.EXCLUDE
configurations.compileClasspath.get().forEach {
from(if (it.isDirectory) it else zipTree(it))
}
}
compileKotlin{
kotlinOptions.jvmTarget = "1.8"
}
}
Thanks in advance
My project had a lot of issues and inconsistency so I started a new one and copied all the files / packages, spent an hour redoing all the imports and plugins that my code actually needed to run and it finally worked, the same comments don't work on the previous project
We have an existing plugin project which configures various things (including static analysis), where we want to apply the plugin to the project itself.
The way this currently works for plugins written in Java is, you add the Java src dir to the buildSrc project, and then classes built there can be used in the main project. So I'm trying to get the same thing working for plugins written as Kotlin scripts.
But when I try to build it, compiling buildSrc fails with:
e: C:\Users\Trejkaz\Documents\test\self-applying-gradle-plugin\src\main\kotlin\example.common.gradle.kts: (1, 1): Unresolved reference: allprojects
> Task :buildSrc:compileKotlin FAILED
What's missing in order to make this work?
Further investigation:
If I put a copy of the files in buildSrc/src/main/kotlin, that works.
If I put a copy of the files in buildSrc/src/main/kotlin2 and use srcDirs to set that directory, that fails too. So it really looks like something isn't letting me relocate sources at all.
I pushed a repo to play with this here but what follows is the contents of the build scripts in case it's ever deleted.
The main build.gradle.kts:
import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
plugins {
`java-gradle-plugin`
`kotlin-dsl`
// Matching version in Gradle
kotlin("jvm") version "1.5.31"
}
apply(from = "common-build.gradle.kts")
apply(plugin = "example.common") // 👈 trying to apply the compiled plugin here
group = "org.example"
version = "1.0-SNAPSHOT"
tasks.withType<KotlinCompile> {
kotlinOptions.jvmTarget = "11"
}
In buildSrc/build.gradle.kts, we have this - note that it adds a source dir for the sources in the main directory:
import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
plugins {
`java-gradle-plugin`
`kotlin-dsl`
// Matching version in Gradle
kotlin("jvm") version "1.5.31"
}
apply(from = "../common-build.gradle.kts")
tasks.withType<KotlinCompile> {
kotlinOptions.jvmTarget = "11"
}
kotlin {
sourceSets["main"].kotlin.srcDir("../src/main/kotlin")
}
common-build.gradle.kts has everything common to both build scripts which we've figured out how to move to a common location (notably, the KotlinCompile isn't there, later I'll figure out why I can't move that as well):
repositories {
mavenCentral()
}
dependencies {
// Needed to compile Kotlin stuff but not added by the plugin for some reason
"implementation"("org.jetbrains.kotlin:kotlin-scripting-jvm")
}
The plugin script, src/main/kotlin/example.common.gradle.kts, contains:
allprojects {
// Configure something
}
This turns out to be a bug in Gradle's kotlin-dsl plugin.
The workaround is to add the source dirs before applying the plugin.
import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
plugins {
`java-gradle-plugin`
`kotlin-dsl` apply false
// Matching version in Gradle
kotlin("jvm") version "1.5.31"
}
apply(from = "../common-build.gradle.kts")
tasks.withType<KotlinCompile> {
kotlinOptions.jvmTarget = "11"
}
kotlin {
sourceSets["main"].kotlin.srcDir("../src/main/kotlin")
}
// Workaround for https://github.com/gradle/gradle/issues/21052 -
// apply kotlin-dsl plugin last, because it erroneously fetches source dirs eagerly.
apply(plugin = "org.gradle.kotlin.kotlin-dsl")
...obviously some necessary things are not included from the dependencies.
Once it reaches a call to an external library, it breaks, either with ClassNotFoundException, or without a word.
I started with this skeleton project.
Relevant changes in build.gradle:
application {
mainClassName = 'net.laca.FoKt'
}
(my main function is in fo.kt)
dependencies {
//...
compile "com.sparkjava:spark-core:2.9.3"
implementation 'com.google.code.gson:gson:2.8.6'
implementation fileTree('libs') { include '*.jar' }
}
jar {
archiveBaseName = 'csira'
// Uncommend the last two lines to build a "fat" jar with `./gradlew jar`,
// and run it without Gradle's help: `java -jar build/libs/skeleton.jar`
manifest { attributes 'Main-Class': 'net.laca.FoKt' }
from { configurations.compile.collect { it.isDirectory() ? it : zipTree(it) } }
}
versions: Kotlin 1.4.20, Java 11, Gradle 6.7.1
Allegedly it should work this way. As it does if I start it with gradle run.
But when I start it with java -jar build/libs/csira.jar after gradle jar, it doesn't.
Relevant parts of fo.kt:
package net.laca
import spark.Spark.*
import com.google.gson.GsonBuilder
fun main(args: Array<String>) {
before("/*")
{ req, res ->
res.type("application/json")
println("hÃvás: ${req.requestMethod()} ${req.pathInfo()} " + req.queryString())
println(GsonBuilder().create().toJson(req.queryMap().toMap())) //line 14
//...
}
At GsonBuilder it breaks:
java.lang.NoClassDefFoundError: com/google/gson/GsonBuilder
at net.laca.FoKt$main$1.handle(fo.kt:14)
at spark.FilterImpl$1.handle(FilterImpl.java:73)
at spark.http.matching.BeforeFilters.execute(BeforeFilters.java:48)
at spark.http.matching.MatcherFilter.doFilter(MatcherFilter.java:133)
at ...
...
Caused by: java.lang.ClassNotFoundException: com.google.gson.GsonBuilder
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:602)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
... 19 more
And when I take/comment out the 14th line, and it reaches a call to my own jar in /libs:
get("/whatever")
{
println("before")
com.zz.app.MyScalaClass.apply().myFun()
println("after")
}
then the last thing I see is before, the rest is silence.
It happens because your jar task is configured incorrectly. To understand why, look at your dependencies:
dependencies {
//...
compile "com.sparkjava:spark-core:2.9.3"
implementation 'com.google.code.gson:gson:2.8.6'
implementation fileTree('libs') { include '*.jar' }
}
You are using both the compile and implementation configurations. The former is deprecated and should not be used by the way.
Then look at the jar task:
jar {
archiveBaseName = 'csira'
// Uncommend the last two lines to build a "fat" jar with `./gradlew jar`,
// and run it without Gradle's help: `java -jar build/libs/skeleton.jar`
manifest { attributes 'Main-Class': 'net.laca.FoKt' }
from { configurations.compile.collect { it.isDirectory() ? it : zipTree(it) } }
}
The from part instructs Gradle to collect all dependencies from the compile configuration only, and this will ignore the implementation configuration completely.
While you could change "compile" to "implementation" everywhere, the correct way to construct a fat jar is to actually collect from the runtimeClasspath configuration. This one extends other configurations like compile and implementation, but also runtimeOnly which you might find handy in the future.
There is actually also an example of how to do this in the Gradle user guide. To adapt it for your project, it should look like:
jar {
archiveBaseName = 'csira'
manifest { attributes 'Main-Class': 'net.laca.FoKt' }
dependsOn configurations.runtimeClasspath
from {
configurations.runtimeClasspath.findAll { it.name.endsWith('jar') }.collect { zipTree(it) }
}
}
The extra dependsOn line ensures that the runtimeClasspath configuration is completely resolved before trying to use it. Another difference is that it only collects jar files.
I recently switched from old 1.2 multiplatform into 1.3. Difference is, there's one one build.gradle file per multiplatform module (I got 5 of them) so a lot less configuration.
However I can't seem to be able to configure creating runnable fat jar with all dependencies from jvm platform.
I used to use standard "application" plugin in my jvm project and jar task, but that does not work anymore. I found there's "jvmJar" task and I modified it (set Main-class), but created jar doesn't contain dependencies and crashes on ClassNotFoundException. How do I do it?
This is what I have now:
jvm() {
jvmJar {
manifest {
attributes 'Main-Class': 'eu.xx.Runner'
}
from { configurations.compile.collect { it.isDirectory() ? it : zipTree(it) } }
}
}
I did hit that bump and used this work around.
1. Restructure your project
Lets call your project Project.
create another submodule say subA, which will have the gradle notation Project:subA
now, subA has your multiplatform code in it (It is the gradle project with apply :kotlin-multiplafrom) in its build.gradle
2. Add Another submodule
create another submodule which targets only jvm say subB, which will have the gradle notation Project:subB
So, subB will have plugins: 'application' and 'org.jetbrains.kotlin.jvm'
3. Add your module as a gradle dependency (see my build.gradle)
plugins {
id 'org.jetbrains.kotlin.jvm' version '1.3.31'
id "application"
}
apply plugin: "kotlinx-serialization"
group 'tz.or.self'
version '0.0.0'
mainClassName = "com.example.MainKt"
sourceCompatibility = 1.8
compileKotlin {
kotlinOptions.jvmTarget = "1.8"
}
dependencies {
implementation project(':subA')
}
you can proceed and build subB as you would a regular java project or even use the existing plugins, it will work
Got it working with the multiplatform plugin in kotlin 1.3.61:
The following works for a main file in src/jvmMain/kotlin/com/example/Hello.kt
Hello.kt must also specify its package as package com.example
I configured my jvm target in this way:
kotlin {
targets {
jvm()
configure([jvm]) {
withJava()
jvmJar {
manifest {
attributes 'Main-Class': 'com.example.HelloKt'
}
from { configurations.runtimeClasspath.collect { it.isDirectory() ? it : zipTree(it) } }
}
}
}
}
Got it to work with a slightly modified version of what luca992 did:
kotlin {
jvm() {
withJava()
jvmJar {
manifest {
attributes 'Main-Class': 'sample.MainKt'
}
from { configurations.runtimeClasspath.collect { it.isDirectory() ? it : zipTree(it) } }
}
}
...
}
The only way to get gradle/multiplatform working appears to be endless trial and error; It's a nightmare, it's not being built as a "build" system so much as a "build system"; to put it another way, these two tools (together or in isolation) are a means of implementing only a single software development life cycle that the plugin maker intended, however, if you've engineered a desired software lifecycle and CI/CD system and now your trying to implement that engineering, it will be MUCH harder to do it with these tools than it would be to do it with scripts, code or maven. There are a number of reasons for this:
Massive changing in coding convention due to the plugin makers only exposing bar minimum configurability, probably only giving access to the things they need for their own personal project.
Very poor documentation updates; Kotlin, gradle and plugins are changing so rapidly I have begun to seriously question the usefulness of these tools.
Thus, at the time of writing this seems to be the correct syntax to use when using kotlin 1.3.72, multiplatform 1.3.72, ktor 1.3.2 and gradle 6.2.2 (using the kts format).
Note the fatJar seems to assemble correctly but won't run, it can't find the class, so I included the second runLocally task I've been using in the mean time.
This isn't a complete solution so I hate posting it on here, but from what I can tell... it is the most complete and up to date solution I can find documented anywhere.
//Import variables from gradle.properties
val environment: String by project
val kotlinVersion: String by project
val ktorVersion: String by project
val kotlinExposedVersion: String by project
val mySqlConnectorVersion: String by project
val logbackVersion: String by project
val romeToolsVersion: String by project
val klaxonVersion: String by project
val kotlinLoggingVersion: String by project
val skrapeItVersion: String by project
val jsoupVersion: String by project
val devWebApiServer: String by project
val devWebApiServerVersion: String by project
//Build File Configuration
plugins {
java
kotlin("multiplatform") version "1.3.72"
}
group = "com.app"
version = "1.0-SNAPSHOT"
repositories {
mavenCentral()
jcenter()
jcenter {
url = uri("https://kotlin.bintray.com/kotlin-js-wrappers")
}
maven {
url = uri("https://jitpack.io")
}
}
//Multiplatform Configuration
kotlin {
jvm {
compilations {
val main = getByName("main")
tasks {
register<Jar>("buildFatJar") {
group = "application"
manifest {
attributes["Implementation-Title"] = "Gradle Jar File Example"
attributes["Implementation-Version"] = archiveVersion
attributes["Main-Class"] = "com.app.BackendAppKt"
}
archiveBaseName.set("${project.name}-fat")
from(main.output.classesDirs, main.compileDependencyFiles)
with(jar.get() as CopySpec)
}
register<JavaExec>("runLocally") {
group = "application"
setMain("com.app.BackendAppKt")
classpath = main.output.classesDirs
classpath += main.compileDependencyFiles
}
}
}
}
js {
browser { EXCLUDED FOR LENGTH }
}
sourceSets { EXCLUDED FOR LENGTH }
}
As titled, I'd like to know how to modify the gradle.build.kts in order to have a task to create a unique jar with all the dependencies (kotlin lib included) inside.
I found this sample in Groovy:
//create a single Jar with all dependencies
task fatJar(type: Jar) {
manifest {
attributes 'Implementation-Title': 'Gradle Jar File Example',
'Implementation-Version': version,
'Main-Class': 'com.mkyong.DateUtils'
}
baseName = project.name + '-all'
from { configurations.compile.collect { it.isDirectory() ? it : zipTree(it) } }
with jar
}
But I have no idea how I could write that in kotlin, other than:
task("fatJar") {
}
Here is a version that does not use a plugin, more like the Groovy version.
import org.gradle.jvm.tasks.Jar
val fatJar = task("fatJar", type = Jar::class) {
baseName = "${project.name}-fat"
manifest {
attributes["Implementation-Title"] = "Gradle Jar File Example"
attributes["Implementation-Version"] = version
attributes["Main-Class"] = "com.mkyong.DateUtils"
}
from(configurations.runtime.map({ if (it.isDirectory) it else zipTree(it) }))
with(tasks["jar"] as CopySpec)
}
tasks {
"build" {
dependsOn(fatJar)
}
}
Also explained here
Some commenters pointed out that this does not work anymore with newer Gradle versions.
Update tested with Gradle 5.4.1:
import org.gradle.jvm.tasks.Jar
val fatJar = task("fatJar", type = Jar::class) {
baseName = "${project.name}-fat"
manifest {
attributes["Implementation-Title"] = "Gradle Jar File Example"
attributes["Implementation-Version"] = version
attributes["Main-Class"] = "com.mkyong.DateUtils"
}
from(configurations.runtimeClasspath.get().map({ if (it.isDirectory) it else zipTree(it) }))
with(tasks.jar.get() as CopySpec)
}
tasks {
"build" {
dependsOn(fatJar)
}
}
Note the difference in configurations.runtimeClasspath.get() and with(tasks.jar.get() as CopySpec).
Here are 4 ways to do this. Note that the first 3 methods modify the existing Jar task of Gradle.
Method 1: Placing library files beside the result JAR
This method does not need application or any other plugins.
tasks.jar {
manifest.attributes["Main-Class"] = "com.example.MyMainClass"
manifest.attributes["Class-Path"] = configurations
.runtimeClasspath
.get()
.joinToString(separator = " ") { file ->
"libs/${file.name}"
}
}
Note that Java requires us to use relative URLs for the Class-Path attribute. So, we cannot use the absolute path of Gradle dependencies (which is also prone to being changed and not available on other systems). If you want to use absolute paths, maybe this workaround will work.
Create the JAR with the following command:
./gradlew jar
The result JAR will be created in build/libs/ directory by default.
After creating your JAR, copy your library JARs in libs/ sub-directory of where you put your result JAR. Make sure your library JAR files do not contain space in their file name (their file name should match the one specified by ${file.name} variable above in the task).
Method 2: Embedding the libraries in the result JAR file (fat or uber JAR)
This method too does not need any Gradle plugin.
tasks.jar {
manifest.attributes["Main-Class"] = "com.example.MyMainClass"
val dependencies = configurations
.runtimeClasspath
.get()
.map(::zipTree) // OR .map { zipTree(it) }
from(dependencies)
duplicatesStrategy = DuplicatesStrategy.EXCLUDE
}
Creating the JAR is exactly the same as the previous method.
Method 3: Using the Shadow plugin (to create a fat or uber JAR)
plugins {
id("com.github.johnrengelman.shadow") version "6.0.0"
}
// Shadow task depends on Jar task, so these configs are reflected for Shadow as well
tasks.jar {
manifest.attributes["Main-Class"] = "org.example.MainKt"
}
Create the JAR with this command:
./gradlew shadowJar
See Shadow documentations for more information about configuring the plugin.
Method 4: Creating a new task (instead of modifying the Jar task)
tasks.create("MyFatJar", Jar::class) {
group = "my tasks" // OR, for example, "build"
description = "Creates a self-contained fat JAR of the application that can be run."
manifest.attributes["Main-Class"] = "com.example.MyMainClass"
duplicatesStrategy = DuplicatesStrategy.EXCLUDE
val dependencies = configurations
.runtimeClasspath
.get()
.map(::zipTree)
from(dependencies)
with(tasks.jar.get())
}
Running the created JAR
java -jar my-artifact.jar
The above solutions were tested with:
Java 17
Gradle 7.1 (which uses Kotlin 1.4.31 for .kts build scripts)
See the official Gradle documentation for creating uber (fat) JARs.
For more information about manifests, see Oracle Java Documentation: Working with Manifest files.
For difference between tasks.create() and tasks.register() see this post.
Note that your resource files will be included in the JAR file automatically (assuming they were placed in /src/main/resources/ directory or any custom directory set as resources root in the build file). To access a resource file in your application, use this code (note the / at the start of names):
Kotlin
val vegetables = MyClass::class.java.getResource("/vegetables.txt").readText()
// Alternative ways:
// val vegetables = object{}.javaClass.getResource("/vegetables.txt").readText()
// val vegetables = MyClass::class.java.getResourceAsStream("/vegetables.txt").reader().readText()
// val vegetables = object{}.javaClass.getResourceAsStream("/vegetables.txt").reader().readText()
Java
var stream = MyClass.class.getResource("/vegetables.txt").openStream();
// OR var stream = MyClass.class.getResourceAsStream("/vegetables.txt");
var reader = new BufferedReader(new InputStreamReader(stream));
var vegetables = reader.lines().collect(Collectors.joining("\n"));
Here is how to do it as of Gradle 6.5.1, Kotlin/Kotlin-Multiplatform 1.3.72, utilizing a build.gradle.kts file and without using an extra plugin which does seem unnecessary and problematic with multiplatform;
Note: in reality, few plugins work well with the multiplatform plugin from what I can tell, which is why I suspect its design philosophy is so verbose itself. It's actually fairly elegant IMHO, but not flexible or documented enough so it takes a ton of trial and error to setup even WITHOUT additional plugins.
Hope this helps others.
kotlin {
jvm {
compilations {
val main = getByName("main")
tasks {
register<Jar>("fatJar") {
group = "application"
manifest {
attributes["Implementation-Title"] = "Gradle Jar File Example"
attributes["Implementation-Version"] = archiveVersion
attributes["Main-Class"] = "[[mainClassPath]]"
}
archiveBaseName.set("${project.name}-fat")
from(main.output.classesDirs, main.compileDependencyFiles)
with(jar.get() as CopySpec)
}
}
}
}
}
You could use the ShadowJar plugin to build a fat jar:
import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
buildscript {
repositories {
mavenCentral()
gradleScriptKotlin()
}
dependencies {
classpath(kotlinModule("gradle-plugin"))
classpath("com.github.jengelman.gradle.plugins:shadow:1.2.3")
}
}
apply {
plugin("kotlin")
plugin("com.github.johnrengelman.shadow")
}
repositories {
mavenCentral()
}
val shadowJar: ShadowJar by tasks
shadowJar.apply {
manifest.attributes.apply {
put("Implementation-Title", "Gradle Jar File Example")
put("Implementation-Version" version)
put("Main-Class", "com.mkyong.DateUtils")
}
baseName = project.name + "-all"
}
Simply run the task with 'shadowJar'.
NOTE: This assumes you're using GSK 0.7.0 (latest as of 02/13/2017).