Repository export read-only lock (#1519)

* Lock repository for read-only access only while exporting
* Create read-only check api

Co-authored-by: René Pfeuffer <rene.pfeuffer@cloudogu.com>

scm-webapp/src/main/java/sonia/scm/api/v2/resources/RepositoryDto.java

@@ -58,6 +58,7 @@ public class RepositoryDto extends HalRepresentation implements CreateRepository
   @NotEmpty
   private String type;
   private boolean archived;
+  private boolean exporting;
 
   RepositoryDto(Links links, Embedded embedded) {
     super(links, embedded);

scm-webapp/src/main/java/sonia/scm/api/v2/resources/RepositoryExportResource.java

@@ -161,12 +161,7 @@ public class RepositoryExportResource {
                                        @PathParam("name") String name
   ) {
     Repository repository = getVerifiedRepository(namespace, name);
-    StreamingOutput output = os -> fullScmRepositoryExporter.export(repository, os);
-
-    return Response
-      .ok(output, "application/x-gzip")
-      .header("content-disposition", createContentDispositionHeaderValue(repository, "tar.gz"))
-      .build();
+    return exportFullRepository(repository);
   }
 
   private Repository getVerifiedRepository(String namespace, String name) {
@@ -186,6 +181,15 @@ public class RepositoryExportResource {
     return repository;
   }
 
+  private Response exportFullRepository(Repository repository) {
+    StreamingOutput output = os -> fullScmRepositoryExporter.export(repository, os);
+
+    return Response
+      .ok(output, "application/x-gzip")
+      .header("content-disposition", createContentDispositionHeaderValue(repository, "tar.gz"))
+      .build();
+  }
+
   private Response exportRepository(Repository repository, boolean compressed) {
     StreamingOutput output;
     String fileExtension;

scm-webapp/src/main/java/sonia/scm/api/v2/resources/RepositoryToRepositoryDtoMapper.java

@@ -27,9 +27,12 @@ package sonia.scm.api.v2.resources;
 import de.otto.edison.hal.Embedded;
 import de.otto.edison.hal.Link;
 import de.otto.edison.hal.Links;
+import org.mapstruct.AfterMapping;
 import org.mapstruct.Mapper;
+import org.mapstruct.MappingTarget;
 import org.mapstruct.ObjectFactory;
 import sonia.scm.config.ScmConfiguration;
+import sonia.scm.repository.DefaultRepositoryExportingCheck;
 import sonia.scm.repository.Feature;
 import sonia.scm.repository.HealthCheckFailure;
 import sonia.scm.repository.NamespaceStrategy;
@@ -70,6 +73,11 @@ public abstract class RepositoryToRepositoryDtoMapper extends BaseMapper<Reposit
   @Override
   public abstract RepositoryDto map(Repository modelObject);
 
+  @AfterMapping
+  void setExporting(Repository repository, @MappingTarget RepositoryDto repositoryDto) {
+    repositoryDto.setExporting(DefaultRepositoryExportingCheck.isRepositoryExporting(repository.getId()));
+  }
+
   @ObjectFactory
   RepositoryDto createDto(Repository repository) {
     Links.Builder linksBuilder = linkingTo().self(resourceLinks.repository().self(repository.getNamespace(), repository.getName()));

scm-webapp/src/main/java/sonia/scm/importexport/FullScmRepositoryExporter.java

@@ -29,6 +29,7 @@ import org.apache.commons.compress.archivers.tar.TarArchiveOutputStream;
 import org.apache.commons.compress.compressors.gzip.GzipCompressorOutputStream;
 import sonia.scm.ContextEntry;
 import sonia.scm.repository.Repository;
+import sonia.scm.repository.RepositoryExportingCheck;
 import sonia.scm.repository.api.ExportFailedException;
 import sonia.scm.repository.api.RepositoryService;
 import sonia.scm.repository.api.RepositoryServiceFactory;
@@ -54,25 +55,36 @@ public class FullScmRepositoryExporter {
   private final RepositoryServiceFactory serviceFactory;
   private final TarArchiveRepositoryStoreExporter storeExporter;
   private final WorkdirProvider workdirProvider;
+  private final RepositoryExportingCheck repositoryExportingCheck;
 
   @Inject
   public FullScmRepositoryExporter(EnvironmentInformationXmlGenerator environmentGenerator,
                                    RepositoryMetadataXmlGenerator metadataGenerator,
                                    RepositoryServiceFactory serviceFactory,
-                                   TarArchiveRepositoryStoreExporter storeExporter, WorkdirProvider workdirProvider) {
+                                   TarArchiveRepositoryStoreExporter storeExporter,
+                                   WorkdirProvider workdirProvider,
+                                   RepositoryExportingCheck repositoryExportingCheck) {
     this.environmentGenerator = environmentGenerator;
     this.metadataGenerator = metadataGenerator;
     this.serviceFactory = serviceFactory;
     this.storeExporter = storeExporter;
     this.workdirProvider = workdirProvider;
+    this.repositoryExportingCheck = repositoryExportingCheck;
   }
 
   public void export(Repository repository, OutputStream outputStream) {
+    repositoryExportingCheck.withExportingLock(repository, () -> {
+      exportInLock(repository, outputStream);
+      return null;
+    });
+  }
+
+  private void exportInLock(Repository repository, OutputStream outputStream) {
     try (
       RepositoryService service = serviceFactory.create(repository);
       BufferedOutputStream bos = new BufferedOutputStream(outputStream);
       GzipCompressorOutputStream gzos = new GzipCompressorOutputStream(bos);
-      TarArchiveOutputStream taos = new TarArchiveOutputStream(gzos);
+      TarArchiveOutputStream taos = new TarArchiveOutputStream(gzos)
     ) {
       writeEnvironmentData(taos);
       writeMetadata(repository, taos);

scm-webapp/src/main/java/sonia/scm/lifecycle/modules/BootstrapModule.java

@@ -36,8 +36,10 @@ import sonia.scm.io.FileSystem;
 import sonia.scm.lifecycle.DefaultRestarter;
 import sonia.scm.lifecycle.Restarter;
 import sonia.scm.plugin.PluginLoader;
+import sonia.scm.repository.DefaultRepositoryExportingCheck;
 import sonia.scm.repository.EventDrivenRepositoryArchiveCheck;
 import sonia.scm.repository.RepositoryArchivedCheck;
+import sonia.scm.repository.RepositoryExportingCheck;
 import sonia.scm.repository.RepositoryLocationResolver;
 import sonia.scm.repository.xml.MetadataStore;
 import sonia.scm.repository.xml.PathBasedRepositoryLocationResolver;
@@ -100,6 +102,7 @@ public class BootstrapModule extends AbstractModule {
 
     // bind core
     bind(RepositoryArchivedCheck.class, EventDrivenRepositoryArchiveCheck.class);
+    bind(RepositoryExportingCheck.class, DefaultRepositoryExportingCheck.class);
     bind(ConfigurationStoreFactory.class, JAXBConfigurationStoreFactory.class);
     bind(ConfigurationEntryStoreFactory.class, JAXBConfigurationEntryStoreFactory.class);
     bind(DataStoreFactory.class, JAXBDataStoreFactory.class);

scm-webapp/src/main/java/sonia/scm/repository/DefaultRepositoryManager.java

@@ -39,7 +39,6 @@ import sonia.scm.NoChangesMadeException;
 import sonia.scm.NotFoundException;
 import sonia.scm.SCMContextProvider;
 import sonia.scm.Type;
-import sonia.scm.config.ScmConfiguration;
 import sonia.scm.event.ScmEventBus;
 import sonia.scm.security.AuthorizationChangedEvent;
 import sonia.scm.security.KeyGenerator;
@@ -79,7 +78,6 @@ public class DefaultRepositoryManager extends AbstractRepositoryManager {
   private static final String THREAD_NAME = "Hook-%s";
   private static final Logger logger =
     LoggerFactory.getLogger(DefaultRepositoryManager.class);
-  private final ScmConfiguration configuration;
   private final ExecutorService executorService;
   private final Map<String, RepositoryHandler> handlerMap;
   private final KeyGenerator keyGenerator;
@@ -89,11 +87,9 @@ public class DefaultRepositoryManager extends AbstractRepositoryManager {
   private final ManagerDaoAdapter<Repository> managerDaoAdapter;
 
   @Inject
-  public DefaultRepositoryManager(ScmConfiguration configuration,
-                                  SCMContextProvider contextProvider, KeyGenerator keyGenerator,
+  public DefaultRepositoryManager(SCMContextProvider contextProvider, KeyGenerator keyGenerator,
                                   RepositoryDAO repositoryDAO, Set<RepositoryHandler> handlerSet,
                                   Provider<NamespaceStrategy> namespaceStrategyProvider) {
-    this.configuration = configuration;
     this.keyGenerator = keyGenerator;
     this.repositoryDAO = repositoryDAO;
     this.namespaceStrategyProvider = namespaceStrategyProvider;