Use Maven to Build the Docs

The rest of the project uses maven and the github workflow was attempting
to use Maven.

Author: rwinch

.gitignore

@@ -11,3 +11,5 @@
 /*.iws
 !/.idea/checkstyle-idea.xml
 !/.idea/externalDependencies.xml
+node_modules/
+target/

.mvn/wrapper/maven-wrapper.jar

@@ -0,0 +1,2 @@
+distributionUrl=https://repo1.maven.org/maven2/org/apache/maven/apache-maven/3.8.9/apache-maven-3.8.9-bin.zip
+

.mvn/wrapper/maven-wrapper.properties

@@ -8,18 +8,32 @@ This README covers how to build the docs in a software branch as well as how to
 
 == Building the Site
 
-You can build the entire site by invoking the following and then viewing the site at `build/site/index.html`
+To build the entire site invoke the following command:
 
 [source,bash]
 ----
-./gradlew antora
+./mvnw antora
 ----
 
+You will then be able to view the site at `target/site/index.html`
+
 == Building a Specific Branch
 
 You can build a specific branch and then viewing the branch specific site at `build/site/index.html`.
 
 [source,bash]
 ----
-./gradlew antora
+export BUILD_VERSION=4.0.0-SNAPSHOT
+export BUILD_REFNAME=main
+./mvnw antora
+----
+
+You will then be able to see the site at `build/site/`
+
+[NOTE]
+====
+If you get the following error, then you must first build the full site and publish it so that a partial builds are supported.
+----
+FATAL (antora): https://docs.spring.io/spring-shell/reference/site-manifest.json returned response code 404 (Not Found)
 ----
+====

README.adoc

@@ -11,7 +11,7 @@ git:
   ensure_git_suffix: false
 content:
   sources:
-  - url: https://github.com/spring-projects/spring-shell
+  - url: .
     # Refname matching:
     # https://docs.antora.org/antora/latest/playbook/content-refname-matching/
     branches: [ main,'({3..9}).+({0..9}).x', '!(3.0.x)', '!(3.1.x)' ]