Changelog generation

buildSrc/build.gradle

@@ -0,0 +1,7 @@
+apply plugin: 'groovy'
+
+dependencies {
+    compile gradleApi()
+    compile localGroovy()
+}
+

buildSrc/src/main/groovy/kcauldron/CreateChangelog.groovy

@@ -0,0 +1,59 @@
+package kcauldron
+
+import org.gradle.api.GradleException
+import org.gradle.api.GradleScriptException
+import org.gradle.api.file.FileCollection
+import org.gradle.api.internal.file.copy.CopyAction
+import org.gradle.api.internal.file.copy.CopyActionProcessingStream
+import org.gradle.api.internal.tasks.SimpleWorkResult
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.SkipWhenEmpty
+import org.gradle.api.tasks.WorkResult
+import org.gradle.api.tasks.bundling.AbstractArchiveTask
+
+public class CreateChangelog extends AbstractArchiveTask {
+    @Input
+    def String oldChangelogUrl
+    @Input
+    def String hash
+    @Input
+    def String message
+    @Input
+    def String version
+    @Input
+    def String format = "# <version>: <hash>\n<message>\n\n"
+
+    @Override
+    FileCollection getSource() {
+        return project.files(project.buildDir)
+    }
+
+    @Override
+    protected CopyAction createCopyAction() {
+        return new CopyAction() {
+            @Override
+            WorkResult execute(CopyActionProcessingStream stream) {
+                def oldChangelog;
+                try {
+                    oldChangelog = new URL(oldChangelogUrl).text.trim();
+                } catch (Exception e) {
+                    if (!project.hasProperty('ignoreOldChangelog'))
+                        throw new GradleException('Error occurred during fetching latest log', e)
+                    oldChangelog = ''
+                    e.printStackTrace();
+                }
+                try {
+                    def newMessage = '';
+                    message.eachLine { newMessage += '   ' + it + '\n' }
+                    def append = format.replace('<version>', version).replace('<hash>', hash).replace('<message>', message)
+                    def changelog = append + oldChangelog;
+                    archivePath.write(changelog.trim(), 'utf-8')
+                    return new SimpleWorkResult(true);
+                } catch(Exception e) {
+                    e.printStackTrace();
+                    return new SimpleWorkResult(false);
+                }
+            }
+        }
+    }
+}