springBoot2.0 gradle 多模块项目打包问题。

Question

项目是用springBoot+gradle生成的，后来改成了多模块，结果打包的时候报错：The value of a manifest attribute must not be null (Key=Start-Class)
这个start-class应该就是springboot启动的application类，不知道是不是因为我改成了多模块项目，gradle配置文件没写好，所以导致拿不到start-class。

以下是build.gradle文件（springboot版本原本是2.0.0 M7，后来改成了2.0.1.BUILD-SNAPSHOT）：

apply from: "./libraries.gradle"

buildscript {
    ext {
        springBootVersion = '2.0.1.BUILD-SNAPSHOT'
        mybatisGeneratorVersion = '1.4'
    }
    repositories {
        mavenCentral()
        maven { url "https://repo.spring.io/snapshot" }
        maven { url "https://repo.spring.io/milestone" }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
    }
}

apply plugin: 'java'
apply plugin: 'idea'
apply plugin: 'eclipse'
apply plugin: 'org.springframework.boot'
apply plugin: 'io.spring.dependency-management'

/*group = 'com.psy'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = 1.8*/

/*repositories {
    mavenCentral()
    maven { url "https://repo.spring.io/snapshot" }
    maven { url "https://repo.spring.io/milestone" }
}*/

//configuration for all projects
allprojects {
    apply plugin: 'java'
    group 'com.psy'
    version = '0.0.1-SNAPSHOT'
    sourceCompatibility = 1.8
    targetCompatibility = 1.8

    repositories {
        mavenCentral()
        maven { url "https://repo.spring.io/snapshot" }
        maven { url "https://repo.spring.io/milestone" }
    }

    /*jar {
        enabled = true
        baseName = 'psy'
        version = '0.5.0'
        manifest {
            attributes "Manifest-Version": 1.0,
                       'Main-Class': 'org.springframework.boot.loader.JarLauncher',
                    'Start-Class': 'com.psy.metrics.MetricsApplication'
        }
    }*/

    /*bootJar {
        classifier = 'app'
        baseName = 'psy'
        version = '0.5.0'
        manifest {
            attributes "Manifest-Version": 1.0,
                        'Main-Class': 'org.springframework.boot.loader.JarLauncher',
                    'Start-Class': 'com.psy.metrics.MetricsApplication'
        }
    }*/
}

//find out the java projects
ext.javaProjects = subprojects.findAll { project -> project.name != 'docs' && project.name != 'manual' && project.name != 'guides'}

project("web") {
    description = "The web module of metrics project"

    dependencies {
        compile(project(":service"))
        compile(project(":common"))
        compile(libraries.shiro_spring)
        compile(libraries.shiro_redis)
        compile(libraries.spring_boot_redis)
        compile(libraries.spring_boot_starter_actuator)
        compile(libraries.spring_boot_starter)
        compile(libraries.spring_boot_starter_web)
        testCompile(libraries.spring_boot_starter_test)
    }
}

project("dao") {
    description = "The dao module of metrics project"

    dependencies {
        compile(project(":common"))
        compile(libraries.mysql_connector_java)
    }
}

project("service") {
    description = "The service module of metrics project"

    dependencies {
        compile(project(":common"))
        compile(project(":dao"))
    }
}

project("common") {
    description = "The common module of metrics project"

    dependencies {
        compile(libraries.lombok)
        compile(libraries.orika_core)
        compile(libraries.spring_boot_redis)
        compile(libraries.spring_boot_starter)
        compile(libraries.commons_lang3)
        compile(libraries.guava)
        compile(libraries.javax_validation)
        compile(libraries.poi)
        compile(libraries.poi_ooxml)
        compile(libraries.commons_beanutils)
    }
}

settings.gradle：
rootProject.name = 'metrics'
include 'web'
include 'service'
include 'dao'
include 'common'

报错信息：

有试过在build.gradle里面覆盖bootJar的命令，把start-class强行写上去，虽然能生成jar包，但是并不完整。

求大神们指出一下是哪里出了问题，需要怎么改，万分感谢T T

Answer 1

问题解决了，最根本的原因还是build.gradle构建部分的配置放在了根目录下，没放在启动类所在的模块下，打包bootJar时提示找不到启动类。
另外就算强行把启动类的包名.类名写在start-class上，因为实际上并没有找到这个启动类，所以打出来的包是残缺的。
只要在启动类所在的模块增加一个build.gradle，并把构建部分的配置移过去，就可以正常打包了。
问题解决有赖于：https://my.oschina.net/tangdu...