Prepare for Maven support

Issue spring-iogh-11

Author: rwinch

lib/partial-build-extension.js

@@ -22,8 +22,8 @@ module.exports.register = function ({ config = {} }) {
     if (!version) {
       const { rawgitUrl = 'https://raw.githubusercontent.com' } = config
       const repositoryPath = await getRepositoryPath(this.require('isomorphic-git'), playbook.dir)
-      const propertiesUrl = `${rawgitUrl}/${repositoryPath}/${refname}/gradle.properties`
-      version = await download(get, propertiesUrl).then((contents) => extractVersion(contents, refname))
+      const baseUrl = `${rawgitUrl}/${repositoryPath}/${refname}`
+      version = await getGradleVersion(get, baseUrl, refname)
     }
     if (isBranch && version.endsWith('-SNAPSHOT')) version = version.slice(0, -9)
     const versionsInManifest = Object.values(siteManifestData.components)[0].versions
@@ -53,7 +53,12 @@ function download (get, url) {
   )
 }
 
-function extractVersion (contents, fallback) {
+function getGradleVersion (get, baseUrl, refname) {
+  const gradlePropertiesUrl = `${baseUrl}/gradle.properties`
+  return download(get, gradlePropertiesUrl).then((contents) => extractGradleVersion(contents, refname))
+}
+
+function extractGradleVersion (contents, fallback) {
   for (const line of (contents.toString().trimEnd() + `\nversion=${fallback}`).split('\n')) {
     if (line.startsWith('version=')) return line.slice(8)
   }