Prototyping the extension point that takes advantages of the underlying file system like ZFS. Still very much a work in progress.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@10879 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/FileSystemProvisioner.java

@@ -0,0 +1,59 @@
+package hudson;
+
+import hudson.matrix.MatrixBuild;
+import hudson.model.AbstractBuild;
+import hudson.model.AbstractProject;
+import hudson.model.Computer;
+import hudson.model.Job;
+
+import java.io.IOException;
+import java.io.File;
+
+/**
+ * Prepares and provisions workspaces for {@link AbstractProject}s.
+ *
+ * <p>
+ *
+ *
+ * <p>
+ * STILL A WORK IN PROGRESS. SUBJECT TO CHANGE!
+ *
+ * TODO: is this per {@link Computer}? Per {@link Job}?
+ *
+ * @author Kohsuke Kawaguchi
+ * @since 1.235
+ */
+public abstract class FileSystemProvisioner implements ExtensionPoint {
+    /**
+     * Called very early in the build (before a build places any files
+     * in the workspace, such as SCM checkout) to provision a workspace
+     * for the build.
+     *
+     * <p>
+     * This method can prepare the underlying file system in preparation
+     * for the later {@link #snapshot(AbstractBuild)}.
+     * 
+     *
+     * TODO: the method needs to be able to see the snapshot would
+     * be later needed. In fact, perhaps we should only call this method
+     * when Hudson knows that a snapshot is later needed?
+     */
+    public abstract void prepareWorkspace(AbstractBuild<?,?> build) throws IOException;
+
+    public abstract void discardWorkspace(AbstractProject<?,?> project) throws IOException;
+
+    public abstract void moveWorkspace(AbstractProject<?,?> project, File oldWorkspace, File newWorkspace) throws IOException;
+
+    /**
+     * Obtains the snapshot of the workspace of the given build.
+     *
+     * <p>
+     * The state of the build when this method is invoked depends on
+     * the project type. Most would call this at the end of the build,
+     * but for example {@link MatrixBuild} would call this after
+     * SCM check out so that the state of the fresh workspace
+     * can be then propagated to elsewhere.
+     */
+    public abstract WorkspaceSnapshot snapshot(AbstractBuild<?,?> build) throws IOException;
+
+}