Update docs build

- Fixes #926

build.gradle

@@ -13,22 +13,25 @@ buildscript {
 		eclipseEmfEcoreVersion = '2.11.1-v20150805-0538'
 		eclipseUml2UmlVersion = '5.0.0-v20140602-0749'
 		curatorVersion = '2.11.1'
-		docResourcesVersion = '0.2.1.RELEASE'
+		docResourcesVersion = '0.2.5'
 		awaitilityVersion = '3.1.6'
 		reactorBlockHoundVersion = '1.0.4.RELEASE'
 	}
 	repositories {
 		gradlePluginPortal()
-		maven { url 'https://repo.springsource.org/plugins-release' }
+		maven { url 'https://repo.spring.io/plugins-release' }
 	}
 	dependencies {
 		classpath("io.spring.gradle:propdeps-plugin:0.0.8")
-		classpath('org.asciidoctor:asciidoctor-gradle-plugin:1.6.1')
-		classpath 'org.asciidoctor:asciidoctorj-pdf:1.5.3'
 		classpath("org.springframework.boot:spring-boot-gradle-plugin:$springBootVersion")
 	}
 }
 
+plugins {
+	id 'org.asciidoctor.jvm.convert' version '3.1.0'
+	id 'org.asciidoctor.jvm.pdf' version '3.1.0'
+}
+
 def recipeProjects() {
 	subprojects.findAll { project ->
 		project.name.contains('spring-statemachine-recipes') && project.name != 'spring-statemachine-recipes-common'
@@ -80,7 +83,6 @@ configure(allprojects) {
 
 	repositories {
 		mavenCentral()
-		jcenter()
 		maven { url 'https://repo.springsource.org/libs-snapshot' }
 		maven { url 'https://repo.springsource.org/libs-release' }
 		maven { url 'https://repo.springsource.org/libs-milestone' }
@@ -573,8 +575,6 @@ project('spring-statemachine-samples-common') {
 configure(rootProject) {
 	description = 'Spring State Machine'
 
-	apply plugin: 'org.asciidoctor.gradle.asciidoctor'
-
 	dependencies {
 		// just used to get version into docs
 		compile 'org.springframework:spring-core'
@@ -588,10 +588,6 @@ configure(rootProject) {
 		tasks.findAll { it.name.startsWith('reference') }.each{ it.dependsOn.add('asciidoctor') }
 	}
 
-	asciidoctorj {
-		version = '1.5.8.1'
-	}
-
 	configurations {
 		docs
 	}
@@ -608,25 +604,10 @@ configure(rootProject) {
 		into "$buildDir/asciidoc/assemble"
 	}
 
-	task('reference', type: org.asciidoctor.gradle.AsciidoctorTask){
-		dependsOn 'prepareAsciidocBuild'
-		dependsOn 'copyDocsSamples'
-		backends 'pdf'
-		sourceDir "$buildDir/asciidoc/assemble"
-		sources {
-			include 'index.adoc'
-		}
-		options doctype: 'book', eruby: 'erubis'
-		attributes 'icons': 'font',
-			'sectanchors': '',
-			'toc': '',
-			'source-highlighter' : 'coderay'
-	}
-
 	asciidoctor {
 		dependsOn 'prepareAsciidocBuild'
 		dependsOn 'copyDocsSamples'
-		backends 'html5'
+		baseDirFollowsSourceFile()
 		sourceDir "$buildDir/asciidoc/assemble"
 		sources {
 			include 'index.adoc'
@@ -637,25 +618,37 @@ configure(rootProject) {
 			}
 		}
 		options doctype: 'book', eruby: 'erubis'
-		attributes 'docinfo': 'shared',
-			toc: 'left',
+		attributes \
+			'docinfo': 'shared',
+			'toc': 'left',
 			'toc-levels': '4',
-			// use provided stylesheet
-			stylesdir: "css/",
-			stylesheet: 'spring.css',
+			'stylesdir': "css/",
+			'stylesheet': 'spring.css',
 			'linkcss': true,
 			'icons': 'font',
 			'sectanchors': '',
-			// use provided highlighter
-			'source-highlighter=highlight.js',
-			'highlightjsdir=js/highlight',
-			'highlightjs-theme=github',
 			'idprefix': '',
 			'idseparator': '-',
 			'spring-statemachine-version' : project.version,
 			'spring-version' : getResolvedVersionOf("spring-core"),
 			'spring-boot-version' : getResolvedVersionOf("spring-boot"),
-			revnumber : project.version
+			'revnumber' : project.version
+	}
+
+	asciidoctorPdf {
+		dependsOn 'prepareAsciidocBuild'
+		dependsOn 'copyDocsSamples'
+		baseDirFollowsSourceFile()
+		sourceDir "$buildDir/asciidoc/assemble"
+		sources {
+			include 'index.adoc'
+		}
+		options doctype: 'book', eruby: 'erubis'
+		attributes \
+			'spring-statemachine-version' : project.version,
+			'spring-version' : getResolvedVersionOf("spring-core"),
+			'spring-boot-version' : getResolvedVersionOf("spring-boot"),
+			'revnumber' : project.version
 	}
 
 	dependencies { // for integration tests
@@ -732,7 +725,7 @@ configure(rootProject) {
 		from (api) {
 			into 'api'
 		}
-		from (reference) {
+		from (asciidoctorPdf) {
 			into 'reference'
 			include 'index.pdf'
 		}