Introduce repository config change event to clear caches

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/api/v2/resources/GitRepositoryConfigChangeClearRepositoryCacheListener.java

@@ -0,0 +1,19 @@
+package sonia.scm.api.v2.resources;
+
+import com.github.legman.Subscribe;
+import sonia.scm.EagerSingleton;
+import sonia.scm.event.ScmEventBus;
+import sonia.scm.plugin.Extension;
+import sonia.scm.repository.ClearRepositoryCacheEvent;
+
+import java.util.Objects;
+
+@EagerSingleton @Extension
+public class GitRepositoryConfigChangeClearRepositoryCacheListener {
+  @Subscribe
+  public void sendClearRepositoryCacheEvent(GitRepositoryConfigChangedEvent event) {
+    if (!Objects.equals(event.getOldConfig().getDefaultBranch(), event.getNewConfig().getDefaultBranch())) {
+      ScmEventBus.getInstance().post(new ClearRepositoryCacheEvent(event.getRepository()));
+    }
+  }
+}

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/api/v2/resources/GitRepositoryConfigChangedEvent.java

@@ -0,0 +1,30 @@
+package sonia.scm.api.v2.resources;
+
+import sonia.scm.event.Event;
+import sonia.scm.repository.GitRepositoryConfig;
+import sonia.scm.repository.Repository;
+
+@Event
+public class GitRepositoryConfigChangedEvent {
+  private final Repository repository;
+  private final GitRepositoryConfig oldConfig;
+  private final GitRepositoryConfig newConfig;
+
+  public GitRepositoryConfigChangedEvent(Repository repository, GitRepositoryConfig oldConfig, GitRepositoryConfig newConfig) {
+    this.repository = repository;
+    this.oldConfig = oldConfig;
+    this.newConfig = newConfig;
+  }
+
+  public Repository getRepository() {
+    return repository;
+  }
+
+  public GitRepositoryConfig getOldConfig() {
+    return oldConfig;
+  }
+
+  public GitRepositoryConfig getNewConfig() {
+    return newConfig;
+  }
+}

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/api/v2/resources/GitRepositoryConfigResource.java

@@ -43,9 +43,6 @@ public class GitRepositoryConfigResource {
     Repository repository = getRepository(namespace, name);
     ConfigurationStore<GitRepositoryConfig> repositoryConfigStore = getStore(repository);
     GitRepositoryConfig config = repositoryConfigStore.get();
-    if (config == null) {
-      config = new GitRepositoryConfig();
-    }
     GitRepositoryConfigDto dto = repositoryConfigMapper.map(config, repository);
     return Response.ok(dto).build();
   }

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/api/v2/resources/GitRepositoryConfigStoreProvider.java

@@ -1,7 +1,6 @@
 package sonia.scm.api.v2.resources;
 
 import sonia.scm.event.ScmEventBus;
-import sonia.scm.repository.ClearRepositoryCacheEvent;
 import sonia.scm.repository.GitRepositoryConfig;
 import sonia.scm.repository.Repository;
 import sonia.scm.store.ConfigurationStore;
@@ -34,17 +33,18 @@ public class GitRepositoryConfigStoreProvider {
 
     @Override
     public GitRepositoryConfig get() {
-      return delegate.get();
+      GitRepositoryConfig config = delegate.get();
+      if (config == null) {
+        return new GitRepositoryConfig();
+      }
+      return config;
     }
 
     @Override
-    public void set(GitRepositoryConfig object) {
+    public void set(GitRepositoryConfig newConfig) {
-      delegate.set(object);
+      GitRepositoryConfig oldConfig = get();
-      sendClearRepositoryCacheEvent();
+      delegate.set(newConfig);
-    }
+      ScmEventBus.getInstance().post(new GitRepositoryConfigChangedEvent(repository, oldConfig, newConfig));
-
-    private void sendClearRepositoryCacheEvent() {
-      ScmEventBus.getInstance().post(new ClearRepositoryCacheEvent(repository));
     }
   }
 }