Add support for updating submodules on cloud config server repo refresh

- if cloneSubmodules is enabled, when repo is being refreshed, also
  properly fetch submodule updates
- move cloneSubmodules boolean outside of JGitFactory because this
  property can be changed during runtime and there is no reason for this
  boolean to be copied inside

Closes #1924

Signed-off-by: Tomas Slusny <slusnucky@gmail.com>

Author: deathbeam

spring-cloud-config-server/src/main/java/org/springframework/cloud/config/server/environment/JGitEnvironmentRepository.java

@@ -40,6 +40,7 @@
 import org.eclipse.jgit.api.ResetCommand.ResetType;
 import org.eclipse.jgit.api.Status;
 import org.eclipse.jgit.api.StatusCommand;
+import org.eclipse.jgit.api.SubmoduleUpdateCommand;
 import org.eclipse.jgit.api.TransportCommand;
 import org.eclipse.jgit.api.TransportConfigCallback;
 import org.eclipse.jgit.api.errors.GitAPIException;
@@ -113,7 +114,7 @@ public class JGitEnvironmentRepository extends AbstractScmEnvironmentRepository
 	 */
 	private boolean cloneOnStart;
 
-	private JGitEnvironmentRepository.JGitFactory gitFactory;
+	private JGitEnvironmentRepository.JGitFactory gitFactory = new JGitFactory();
 
 	private String defaultLabel;
 
@@ -146,6 +147,8 @@ public class JGitEnvironmentRepository extends AbstractScmEnvironmentRepository
 	 */
 	private boolean skipSslValidation;
 
+	private boolean cloneSubmodules;
+
 	private boolean tryMasterBranch;
 
 	private final ObservationRegistry observationRegistry;
@@ -167,11 +170,19 @@ public JGitEnvironmentRepository(ConfigurableEnvironment environment, JGitEnviro
 		this.deleteUntrackedBranches = properties.isDeleteUntrackedBranches();
 		this.refreshRate = properties.getRefreshRate();
 		this.skipSslValidation = properties.isSkipSslValidation();
-		this.gitFactory = new JGitFactory(properties.isCloneSubmodules());
+		this.cloneSubmodules = properties.isCloneSubmodules();
 		this.tryMasterBranch = properties.isTryMasterBranch();
 		this.observationRegistry = observationRegistry;
 	}
 
+	public boolean isCloneSubmodules() {
+		return this.cloneSubmodules;
+	}
+
+	public void setCloneSubmodules(boolean cloneSubmodules) {
+		this.cloneSubmodules = cloneSubmodules;
+	}
+
 	public boolean isTryMasterBranch() {
 		return tryMasterBranch;
 	}
@@ -315,6 +326,13 @@ public String refresh(String label) {
 				if (this.deleteUntrackedBranches && fetchStatus != null) {
 					deleteUntrackedLocalBranches(fetchStatus.getTrackingRefUpdates(), git);
 				}
+
+				// update submodules if needed
+				if (cloneSubmodules) {
+					SubmoduleUpdateCommand submoduleUpdate = git.submoduleUpdate().setFetch(true);
+					configureCommand(submoduleUpdate);
+					submoduleUpdate.call();
+				}
 			}
 
 			// checkout after fetch so we can get any new branches, tags, ect.
@@ -669,6 +687,7 @@ private Git copyFromLocalRepository() throws IOException {
 
 	private Git cloneToBasedir() throws GitAPIException {
 		CloneCommand clone = this.gitFactory.getCloneCommandByCloneRepository()
+			.setCloneSubmodules(cloneSubmodules)
 			.setURI(getUri())
 			.setDirectory(getBasedir());
 		configureCommand(clone);
@@ -776,23 +795,13 @@ public void setLastRefresh(long lastRefresh) {
 	 */
 	public static class JGitFactory {
 
-		private final boolean cloneSubmodules;
-
-		public JGitFactory() {
-			this(false);
-		}
-
-		public JGitFactory(boolean cloneSubmodules) {
-			this.cloneSubmodules = cloneSubmodules;
-		}
-
 		public Git getGitByOpen(File file) throws IOException {
 			Git git = Git.open(file);
 			return git;
 		}
 
 		public CloneCommand getCloneCommandByCloneRepository() {
-			CloneCommand command = Git.cloneRepository().setCloneSubmodules(cloneSubmodules);
+			CloneCommand command = Git.cloneRepository();
 			return command;
 		}