[JENKINS-13493] Automatic Git Cache Maintenance API (#862)

* added maintenance to CLI Git
* added logs to maintenance command
* added execution time for maintenance command
* added execution time unit
* tested commit-graph
* tested loose objects
* tested incremental-repack
* tested gc
* init prefetch testing
* added javadoc to maintenance apis
* return boolean after executing git maintenance
* updated tests with boolean

Co-authored-by: Mark Waite <[email protected]>

src/main/java/org/jenkinsci/plugins/gitclient/CliGitAPIImpl.java

@@ -8,7 +8,6 @@
 import edu.umd.cs.findbugs.annotations.NonNull;
 import hudson.EnvVars;
 import hudson.FilePath;
-import hudson.Functions;
 import hudson.Launcher;
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import hudson.Launcher.LocalLauncher;
@@ -3866,4 +3865,49 @@ Output shows SHA1 and tag with (optional) marker for annotated tags
         return tags;
     }
 
+    /** {@inheritDoc} */
+    @Override
+    public boolean maintenance(String task) throws InterruptedException {
+        boolean isExecuted = true;
+        try {
+            listener.getLogger().println("Git maintenance " + task + " started on " + workspace.getName());
+            long startTime = System.currentTimeMillis();
+            if (isAtLeastVersion(2, 30, 0, 0)) {
+                // For prefetch, the command will throw an error for private repo if it has no access.
+                launchCommand("maintenance", "run", "--task=" + task);
+            } else {
+                switch(task) {
+                    case "gc":
+                        launchCommand("gc", "--auto");
+                        break;
+                    case "commit-graph":
+                        if (isAtLeastVersion(2, 19, 0, 0)) {
+                            launchCommand("commit-graph", "write");
+                        } else {
+                            listener.getLogger().println("Error executing commit-graph maintenance task");
+                        }
+                        break;
+                    case "incremental-repack":
+                        if (isAtLeastVersion(2, 25, 0, 0)) {
+                            launchCommand("multi-pack-index", "expire");
+                            launchCommand("multi-pack-index", "repack");
+                        } else {
+                            listener.getLogger().println("Error executing incremental-repack maintenance task");
+                        }
+                        break;
+                    default:
+                        String message = "Invalid legacy git maintenance task " + task + ".";
+                        listener.getLogger().println(message);
+                        throw new GitException(message);
+                }
+            }
+            long endTime = System.currentTimeMillis();
+            listener.getLogger().println("Git maintenance task " + task + " finished on " + workspace.getName() + " in " + (endTime - startTime) + "ms.");
+        } catch (GitException e) {
+            isExecuted = false;
+            listener.getLogger().println("Error executing " + task + " maintenance task");
+            listener.getLogger().println("Mainteance task " + task + " error message: " + e.getMessage());
+        }
+        return isExecuted;
+    }
 }

src/main/java/org/jenkinsci/plugins/gitclient/GitClient.java

@@ -1002,4 +1002,13 @@ public interface GitClient {
      * @throws java.lang.InterruptedException on thread interruption
      */
     Set<GitObject> getTags() throws GitException, InterruptedException;
+
+    /**
+     * Executes git maintenance commands based on the git version.
+     *
+     * @param task a {@link java.lang.String} object. i.e (prefetch/gc/commit-graph/incremental-repack/loose-objects)
+     * @return Boolean if maintenance has been executed or not.
+     * @throws InterruptedException if underlying git operation fails.
+     */
+    boolean maintenance(String task) throws InterruptedException;
 }

src/main/java/org/jenkinsci/plugins/gitclient/JGitAPIImpl.java

@@ -2882,6 +2882,11 @@ public Set<GitObject> getTags() throws GitException {
         return peeledTags;
     }
 
+    @Override
+    public boolean maintenance(String task) {
+        listener.getLogger().println("JGIT doesn't support git maintenance. Use CLIGIT to execute maintenance tasks.");
+        return false;
+    }
     private static class FileRepositoryImpl extends FileRepository {
 
         private final File tempDir;

src/main/java/org/jenkinsci/plugins/gitclient/RemoteGitImpl.java

@@ -921,4 +921,9 @@ public List<Branch> getBranchesContaining(String revspec, boolean allBranches)
     public Set<GitObject> getTags() throws GitException, InterruptedException {
         return proxy.getTags();
     }
+
+    @Override
+    public boolean maintenance(String task) {
+        return false;
+    }
 }