Reinstate single page HTML and PDF docs

Closes gh-16854

Author: philwebb

spring-boot-project/spring-boot-docs/pom.xml

@@ -1442,7 +1442,14 @@
 						<artifactId>asciidoctor-maven-plugin</artifactId>
 						<configuration>
 							<sourceDirectory>${refdocs.build.directory}</sourceDirectory>
-							<outputDirectory>${project.build.directory}/generated-docs/reference/html</outputDirectory>
+							<resources>
+								<resource>
+									<directory>${refdocs.build.directory}</directory>
+									<excludes>
+										<exclude>**/*.*adoc</exclude>
+									</excludes>
+								</resource>
+							</resources>
 							<attributes>
 								<spring-boot-docs-version>${revision}</spring-boot-docs-version>
 								<spring-boot-repo>${spring-boot-repo}</spring-boot-repo>
@@ -1465,6 +1472,11 @@
 								</goals>
 								<configuration>
 									<backend>html5</backend>
+									<sourceDocumentExtensions>
+										<sourceDocumentExtension>adoc</sourceDocumentExtension>
+										<sourceDocumentExtension>htmladoc</sourceDocumentExtension>
+									</sourceDocumentExtensions>
+									<outputDirectory>${project.build.directory}/generated-docs/reference/html</outputDirectory>
 									<sourceHighlighter>highlight.js</sourceHighlighter>
 									<doctype>book</doctype>
 									<attributes>
@@ -1478,6 +1490,53 @@
 									</attributes>
 								</configuration>
 							</execution>
+							<execution>
+								<id>generate-htmlsingle-documentation</id>
+								<phase>prepare-package</phase>
+								<goals>
+									<goal>process-asciidoc</goal>
+								</goals>
+								<configuration>
+									<backend>html5</backend>
+									<sourceDocumentExtensions>
+										<sourceDocumentExtension>htmlsingleadoc</sourceDocumentExtension>
+									</sourceDocumentExtensions>
+									<outputDirectory>${project.build.directory}/generated-docs/reference/htmlsingle</outputDirectory>
+									<sourceHighlighter>highlight.js</sourceHighlighter>
+									<doctype>book</doctype>
+									<attributes>
+										<highlightjsdir>js/highlight</highlightjsdir>
+										<highlightjs-theme>atom-one-dark-reasonable</highlightjs-theme>
+										<linkcss>true</linkcss>
+										<imagesdir>./images</imagesdir>
+										<icons>font</icons>
+										<stylesdir>css/</stylesdir>
+										<stylesheet>spring.css</stylesheet>
+									</attributes>
+								</configuration>
+							</execution>
+							<execution>
+								<id>generate-pdf-documentation</id>
+								<phase>prepare-package</phase>
+								<goals>
+									<goal>process-asciidoc</goal>
+								</goals>
+								<configuration>
+									<backend>pdf</backend>
+									<sourceDocumentExtensions>
+										<sourceDocumentExtension>pdfadoc</sourceDocumentExtension>
+									</sourceDocumentExtensions>
+									<outputDirectory>${project.build.directory}/generated-docs/reference/pdf</outputDirectory>
+									<resources>
+										<resource>
+											<directory>${refdocs.build.directory}</directory>
+											<excludes>
+												<exclude>**/*</exclude>
+											</excludes>
+										</resource>
+									</resources>
+								</configuration>
+							</execution>
 						</executions>
 					</plugin>
 					<plugin>

spring-boot-project/spring-boot-docs/src/main/asciidoc/documentation-overview.adoc

@@ -13,10 +13,12 @@ as a map for the rest of the document.
 [[boot-documentation-about]]
 == About the Documentation
 The Spring Boot reference guide is available as
-<<single-index.adoc#spring-boot-reference-documentation, single page>> or
-<<index.adoc#spring-boot-reference-documentation, multi-page>> documentation.
-The latest copy
-of the reference documentation is available at {spring-boot-docs-current}.
+
+* {spring-boot-docs}/html[Multi-page HTML]
+* {spring-boot-docs}/htmlsingle[Single page HTML]
+* {spring-boot-docs}/pdf/spring-boot-reference.pdf[PDF]
+
+The latest copy is available at {spring-boot-docs-current}.
 
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