Feature do not temp store uploaded files (#763)

* Upload artefacts directly without creating a temp file
* Remove redundant code that checks if user tries to update a directory
* Handle UI upload exceptions, use Spring thread pool
* Clean up code
* Fix review findings
* Fix Sonar findings

Signed-off-by: Stefan Klotz <stefan.klotz@bosch-si.com>
Signed-off-by: Stefan Behl <stefan.behl@bosch-si.com>

hawkbit-repository/hawkbit-repository-api/src/main/java/org/eclipse/hawkbit/repository/model/TargetWithActionType.java

@@ -25,9 +25,7 @@ public class TargetWithActionType {
     private String maintenanceWindowTimeZone;
 
     public TargetWithActionType(final String controllerId) {
-        this.controllerId = controllerId;
+        this(controllerId, ActionType.FORCED, 0);
-        this.actionType = ActionType.FORCED;
-        this.forceTime = 0;
     }
 
     public TargetWithActionType(final String controllerId, final ActionType actionType, final long forceTime) {
@@ -115,4 +113,13 @@ public class TargetWithActionType {
     public String getMaintenanceWindowTimeZone() {
         return maintenanceWindowTimeZone;
     }
+
+    @Override
+    public String toString() {
+        return "TargetWithActionType [controllerId=" + controllerId + ", actionType=" + getActionType() + ", forceTime="
+                + getForceTime() + ", maintenanceSchedule=" + getMaintenanceSchedule() + ", maintenanceWindowDuration="
+                + getMaintenanceWindowDuration() + ", maintenanceWindowTimeZone=" + getMaintenanceWindowTimeZone()
+                + "]";
+    }
+
 }

hawkbit-repository/hawkbit-repository-jpa/src/main/java/org/eclipse/hawkbit/repository/jpa/AbstractDsAssignmentStrategy.java

@@ -215,6 +215,7 @@ public abstract class AbstractDsAssignmentStrategy {
                 .publishEvent(new CancelTargetAssignmentEvent(target, actionId, applicationContext.getId())));
     }
 
+    @SuppressWarnings("squid:S2259")
     JpaAction createTargetAction(final Map<String, TargetWithActionType> targetsWithActionMap, final JpaTarget target,
             final JpaDistributionSet set) {
 

hawkbit-repository/hawkbit-repository-jpa/src/main/java/org/eclipse/hawkbit/repository/jpa/JpaDeploymentManagement.java

@@ -90,6 +90,9 @@ import org.springframework.transaction.support.TransactionTemplate;
 import org.springframework.util.CollectionUtils;
 import org.springframework.validation.annotation.Validated;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.ObjectWriter;
 import com.google.common.base.Joiner;
 import com.google.common.collect.Lists;
 
@@ -100,6 +103,7 @@ import com.google.common.collect.Lists;
 @Transactional(readOnly = true)
 @Validated
 public class JpaDeploymentManagement implements DeploymentManagement {
+
     private static final Logger LOG = LoggerFactory.getLogger(JpaDeploymentManagement.class);
 
     /**
@@ -321,8 +325,10 @@ public class JpaDeploymentManagement implements DeploymentManagement {
         assignmentStrategy.updateTargetStatus(set, targetIds, currentUser);
 
         final Map<String, JpaAction> targetIdsToActions = targets.stream()
-                .map(t -> actionRepository.save(assignmentStrategy.createTargetAction(targetsWithActionMap, t, set)))
+                .map(trg -> createTargetAction(assignmentStrategy, targetsWithActionType, controllerIDs, targets,
-                .collect(Collectors.toMap(a -> a.getTarget().getControllerId(), Function.identity()));
+                        targetsWithActionMap, trg, set))
+                .map(actionRepository::save)
+                .collect(Collectors.toMap(action -> action.getTarget().getControllerId(), Function.identity()));
 
         // create initial action status when action is created so we remember
         // the initial running status because we will change the status
@@ -578,7 +584,6 @@ public class JpaDeploymentManagement implements DeploymentManagement {
     @Override
     public Page<Action> findActiveActionsByTarget(final Pageable pageable, final String controllerId) {
         throwExceptionIfTargetDoesNotExist(controllerId);
-
         return actionRepository.findByActiveAndTarget(pageable, controllerId, true);
     }
 
@@ -592,14 +597,12 @@ public class JpaDeploymentManagement implements DeploymentManagement {
     @Override
     public long countActionsByTarget(final String controllerId) {
         throwExceptionIfTargetDoesNotExist(controllerId);
-
         return actionRepository.countByTargetControllerId(controllerId);
     }
 
     @Override
     public long countActionsByTarget(final String rsqlParam, final String controllerId) {
         throwExceptionIfTargetDoesNotExist(controllerId);
-
         return actionRepository.count(createSpecificationFor(controllerId, rsqlParam));
     }
 
@@ -684,7 +687,6 @@ public class JpaDeploymentManagement implements DeploymentManagement {
     @Override
     public Slice<Action> findActionsByDistributionSet(final Pageable pageable, final long dsId) {
         throwExceptionIfDistributionSetDoesNotExist(dsId);
-
         return actionRepository.findByDistributionSetId(pageable, dsId);
     }
 
@@ -696,14 +698,12 @@ public class JpaDeploymentManagement implements DeploymentManagement {
     @Override
     public Optional<DistributionSet> getAssignedDistributionSet(final String controllerId) {
         throwExceptionIfTargetDoesNotExist(controllerId);
-
         return distributionSetRepository.findAssignedToTarget(controllerId);
     }
 
     @Override
     public Optional<DistributionSet> getInstalledDistributionSet(final String controllerId) {
         throwExceptionIfTargetDoesNotExist(controllerId);
-
         return distributionSetRepository.findInstalledAtTarget(controllerId);
     }
 
@@ -736,7 +736,7 @@ public class JpaDeploymentManagement implements DeploymentManagement {
         return deleteQuery.executeUpdate();
     }
 
-    private static String getQueryForDeleteActionsByStatusAndLastModifiedBeforeString(Database database) {
+    private static String getQueryForDeleteActionsByStatusAndLastModifiedBeforeString(final Database database) {
         return QUERY_DELETE_ACTIONS_BY_STATE_AND_LAST_MODIFIED.getOrDefault(database,
                 QUERY_DELETE_ACTIONS_BY_STATE_AND_LAST_MODIFIED_DEFAULT);
     }
@@ -749,4 +749,52 @@ public class JpaDeploymentManagement implements DeploymentManagement {
         return "#" + Joiner.on(",#").join(elements);
     }
 
+    @SuppressWarnings({ "squid:S1695", "squid:S1696" })
+    private JpaAction createTargetAction(final AbstractDsAssignmentStrategy assignmentStrategy,
+            final Collection<TargetWithActionType> targetsWithActionType, final List<String> controllerIDs,
+            final List<JpaTarget> targets, final Map<String, TargetWithActionType> targetsWithActionMap,
+            final JpaTarget target, final JpaDistributionSet set) {
+        try {
+            return assignmentStrategy.createTargetAction(targetsWithActionMap, target, set);
+        } catch (final NullPointerException e) {
+            dumpDistributionSetAssignment(target, set, targetsWithActionType, controllerIDs, targets,
+                    targetsWithActionMap);
+            throw e;
+        }
+    }
+
+    private void dumpDistributionSetAssignment(final JpaTarget target, final JpaDistributionSet set,
+            final Collection<TargetWithActionType> targetsWithActionType, final List<String> controllerIDs,
+            final List<JpaTarget> targets, final Map<String, TargetWithActionType> targetsWithActionMap) {
+        final ObjectWriter writer = new ObjectMapper().writer();
+        final String correlationID = "DistributionSetAssignmentDump[" + Thread.currentThread().getId() + "]";
+        dump(correlationID, "Target", Objects.toString(target));
+        dump(correlationID, "DistributionSet", Objects.toString(set));
+        if (target != null) {
+            dump(correlationID, "ControllerID", Objects.toString(target.getControllerId()));
+            if (set != null) {
+                dump(correlationID, "Actions", toString(writer,
+                        actionRepository.findByTargetAndDistributionSet(new PageRequest(0, 500), target, set)));
+            }
+        }
+        dump(correlationID, "ControllerIDs", toString(writer, controllerIDs));
+        dump(correlationID, "Targets", toString(writer, targets));
+        dump(correlationID, "TargetsWithActionType", toString(writer, targetsWithActionType));
+        dump(correlationID, "TargetsWithActionMap", toString(writer, targetsWithActionMap));
+    }
+
+    private static void dump(final String prefix, final String key, final String value) {
+        LOG.error("{} >>> {}: {}", prefix, key, value);
+    }
+
+    @SuppressWarnings("squid:S1166")
+    private static String toString(final ObjectWriter writer, final Object o) {
+        try {
+            return writer.writeValueAsString(o);
+        } catch (final JsonProcessingException e) {
+            LOG.error("Object serialization failed", e);
+            return e.getMessage();
+        }
+    }
+
 }

hawkbit-repository/hawkbit-repository-jpa/src/main/java/org/eclipse/hawkbit/repository/jpa/model/JpaAction.java

@@ -209,7 +209,8 @@ public class JpaAction extends AbstractJpaTenantAwareBaseEntity implements Actio
     @Override
     public String toString() {
         return "JpaAction [distributionSet=" + distributionSet.getId() + ", version=" + getOptLockRevision() + ", id="
-                + getId() + "]";
+                + getId() + ", actionType=" + getActionType() + ", isActive=" + isActive() + ",  createdAt="
+                + getCreatedAt() + ", lastModifiedAt=" + getLastModifiedAt() + "]";
     }
 
     @Override

hawkbit-ui/src/main/java/org/eclipse/hawkbit/ui/artifacts/upload/AbstractFileTransferHandler.java

@@ -8,12 +8,12 @@
  */
 package org.eclipse.hawkbit.ui.artifacts.upload;
 
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.Serializable;
+import java.util.Optional;
+import java.util.concurrent.ExecutorService;
 
 import org.apache.commons.lang3.StringUtils;
 import org.eclipse.hawkbit.repository.ArtifactManagement;
@@ -27,13 +27,14 @@ import org.eclipse.hawkbit.ui.artifacts.event.SoftwareModuleEvent.SoftwareModule
 import org.eclipse.hawkbit.ui.artifacts.state.ArtifactUploadState;
 import org.eclipse.hawkbit.ui.artifacts.upload.FileUploadProgress.FileUploadStatus;
 import org.eclipse.hawkbit.ui.utils.SpringContextHelper;
+import org.eclipse.hawkbit.ui.utils.UINotification;
 import org.eclipse.hawkbit.ui.utils.VaadinMessageSource;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.vaadin.spring.events.EventBus;
 import org.vaadin.spring.events.EventBus.UIEventBus;
 
-import com.google.common.io.ByteStreams;
+import com.vaadin.ui.UI;
 
 /**
  * Abstract base class for transferring files from the browser to the
@@ -49,8 +50,6 @@ public abstract class AbstractFileTransferHandler implements Serializable {
 
     private volatile boolean uploadInterrupted;
 
-    private volatile String tempFilePath;
-
     private volatile String failureReason;
 
     private final ArtifactUploadState artifactUploadState;
@@ -61,11 +60,14 @@ public abstract class AbstractFileTransferHandler implements Serializable {
 
     private final VaadinMessageSource i18n;
 
+    protected final UINotification uiNotification;
+
     AbstractFileTransferHandler(final ArtifactManagement artifactManagement, final VaadinMessageSource i18n) {
         this.artifactManagement = artifactManagement;
         this.i18n = i18n;
         this.eventBus = SpringContextHelper.getBean(EventBus.UIEventBus.class);
         this.artifactUploadState = SpringContextHelper.getBean(ArtifactUploadState.class);
+        this.uiNotification = SpringContextHelper.getBean(UINotification.class);
     }
 
     protected boolean isDuplicateFile() {
@@ -99,6 +101,13 @@ public abstract class AbstractFileTransferHandler implements Serializable {
         return i18n;
     }
 
+    protected void startTransferToRepositoryThread(final InputStream inputStream, final FileUploadId fileUploadId,
+            final String mimeType) {
+        SpringContextHelper.getBean("asyncExecutor", ExecutorService.class)
+                .execute(
+                        new TransferArtifactToRepositoryRunnable(inputStream, fileUploadId, mimeType, UI.getCurrent()));
+    }
+
     private void setFailureReason(final String failureReason) {
         this.failureReason = failureReason;
     }
@@ -131,22 +140,13 @@ public abstract class AbstractFileTransferHandler implements Serializable {
     }
 
     protected void publishUploadProgressEvent(final FileUploadId fileUploadId, final long bytesReceived,
-            final long fileSize, final String tempFilePath) {
+            final long fileSize) {
         if (LOG.isTraceEnabled()) {
             LOG.trace("Upload in progress for file {} - {}%", fileUploadId,
                     String.format("%.0f", (double) bytesReceived / (double) fileSize * 100));
         }
         final FileUploadProgress fileUploadProgress = new FileUploadProgress(fileUploadId,
-                FileUploadStatus.UPLOAD_IN_PROGRESS, bytesReceived, fileSize, tempFilePath);
+                FileUploadStatus.UPLOAD_IN_PROGRESS, bytesReceived, fileSize);
-        artifactUploadState.updateFileUploadProgress(fileUploadId, fileUploadProgress);
-        eventBus.publish(this, fileUploadProgress);
-    }
-
-    private void publishUploadSucceeded(final FileUploadId fileUploadId, final long fileSize,
-            final String tempFilePath) {
-        LOG.info("Upload succeeded for file {}", fileUploadId);
-        final FileUploadProgress fileUploadProgress = new FileUploadProgress(fileUploadId,
-                FileUploadStatus.UPLOAD_SUCCESSFUL, fileSize, fileSize, tempFilePath);
         artifactUploadState.updateFileUploadProgress(fileUploadId, fileUploadProgress);
         eventBus.publish(this, fileUploadProgress);
     }
@@ -158,6 +158,19 @@ public abstract class AbstractFileTransferHandler implements Serializable {
         eventBus.publish(this, fileUploadProgress);
     }
 
+    protected void publishUploadSucceeded(final FileUploadId fileUploadId, final long fileSize) {
+        LOG.info("Upload succeeded for file {}", fileUploadId);
+        final FileUploadProgress fileUploadProgress = new FileUploadProgress(fileUploadId,
+                FileUploadStatus.UPLOAD_SUCCESSFUL, fileSize, fileSize);
+        artifactUploadState.updateFileUploadProgress(fileUploadId, fileUploadProgress);
+        eventBus.publish(this, fileUploadProgress);
+    }
+
+    protected void publishArtifactsChanged(final FileUploadId fileUploadId) {
+        eventBus.publish(this,
+                new SoftwareModuleEvent(SoftwareModuleEventType.ARTIFACTS_CHANGED, fileUploadId.getSoftwareModuleId()));
+    }
+
     protected void publishUploadFailedEvent(final FileUploadId fileUploadId, final String failureReason,
             final Exception uploadException) {
         LOG.info("Upload failed for file {} due to {}", fileUploadId,
@@ -180,59 +193,94 @@ public abstract class AbstractFileTransferHandler implements Serializable {
         }
     }
 
-    protected OutputStream createOutputStreamForTempFile() throws IOException {
+    protected static void tryToCloseIOStream(final OutputStream outputStream) {
-
+        if (outputStream != null) {
-        if (isUploadInterrupted()) {
+            try {
-            return ByteStreams.nullOutputStream();
+                outputStream.close();
-        }
+            } catch (final IOException e1) {
-
+                LOG.error("Closing output stream caused an exception {}", e1);
-        final File tempFile = File.createTempFile("spUiArtifactUpload", null);
-
-        // we return the outputstream so we cannot close it here
-        @SuppressWarnings("squid:S2095")
-        final OutputStream out = new FileOutputStream(tempFile);
-
-        tempFilePath = tempFile.getAbsolutePath();
-
-        return out;
-    }
-
-    protected String getTempFilePath() {
-        return tempFilePath;
-    }
-
-    // Exception squid:S3655 - Optional access is checked in
-    // checkIfArtifactDetailsDispalyed subroutine
-    @SuppressWarnings("squid:S3655")
-    protected void transferArtifactToRepository(final FileUploadId fileUploadId, final long fileSize,
-            final String mimeType, final String tempFilePath) {
-
-        final File newFile = new File(tempFilePath);
-
-        final String filename = fileUploadId.getFilename();
-        LOG.info("Transfering tempfile {} - {} to repository", filename, tempFilePath);
-        try (FileInputStream fis = new FileInputStream(newFile)) {
-
-            artifactManagement.create(fis, fileUploadId.getSoftwareModuleId(), filename, null, null, true, mimeType,
-                    fileSize);
-
-            publishUploadSucceeded(fileUploadId, fileSize, tempFilePath);
-
-            eventBus.publish(this, new SoftwareModuleEvent(SoftwareModuleEventType.ARTIFACTS_CHANGED,
-                    fileUploadId.getSoftwareModuleId()));
-
-        } catch (final ArtifactUploadFailedException | InvalidSHA1HashException | InvalidMD5HashException
-                | IOException e) {
-            publishUploadFailedEvent(fileUploadId, i18n.getMessage("message.upload.failed"), e);
-            LOG.error("Failed to transfer file to repository", e);
-        } finally {
-            LOG.debug("Deleting tempfile {} - {}", filename, newFile.getAbsolutePath());
-            if (newFile.exists() && !newFile.delete()) {
-                LOG.error("Could not delete temporary file: {}", newFile.getAbsolutePath());
             }
         }
 
-        publishUploadFinishedEvent(fileUploadId);
+    }
+
+    protected static void tryToCloseIOStream(final InputStream inputStream) {
+        if (inputStream != null) {
+            try {
+                inputStream.close();
+            } catch (final IOException e1) {
+                LOG.error("Closing input stream caused an exception {}", e1);
+            }
+        }
+    }
+
+    private final class TransferArtifactToRepositoryRunnable implements Runnable {
+        private final InputStream inputStream;
+        private final FileUploadId fileUploadId;
+        private final String mimeType;
+        private final UI vaadinUi;
+
+        public TransferArtifactToRepositoryRunnable(final InputStream inputStream, final FileUploadId fileUploadId,
+                final String mimeType, final UI vaadinUi) {
+            this.inputStream = inputStream;
+            this.fileUploadId = fileUploadId;
+            this.mimeType = mimeType;
+            this.vaadinUi = vaadinUi;
+        }
+
+        @Override
+        public void run() {
+            try {
+                UI.setCurrent(vaadinUi);
+                streamToRepository();
+            } catch (final RuntimeException e) {
+                publishUploadFailedEvent(fileUploadId, i18n.getMessage("message.upload.failed"), e);
+                LOG.error("Failed to transfer file to repository", e);
+            } finally {
+                tryToCloseIOStream(inputStream);
+            }
+        }
+
+        private void streamToRepository() {
+            if (fileUploadId == null) {
+                throw new ArtifactUploadFailedException();
+            }
+            final String filename = fileUploadId.getFilename();
+            LOG.info("Transfering file {} directly to repository", filename);
+            final Artifact artifact = uploadArtifact(filename).orElseThrow(ArtifactUploadFailedException::new);
+            if (isUploadInterrupted()) {
+                handleUploadFailure(artifact);
+                return;
+            }
+            publishUploadSucceeded(fileUploadId, artifact.getSize());
+            publishUploadFinishedEvent(fileUploadId);
+            publishArtifactsChanged(fileUploadId);
+        }
+
+        private Optional<Artifact> uploadArtifact(final String filename) {
+            try {
+                return Optional.ofNullable(artifactManagement.create(inputStream, fileUploadId.getSoftwareModuleId(),
+                        filename, null, null, true, mimeType, -1));
+            } catch (final ArtifactUploadFailedException | InvalidSHA1HashException | InvalidMD5HashException e) {
+                LOG.error("Failed to transfer file to repository", e);
+                return Optional.empty();
+            }
+        }
+
+        private void handleUploadFailure(final Artifact artifact) {
+            Exception exception;
+            int tries = 0;
+            do {
+                try {
+                    artifactManagement.delete(artifact.getId());
+                    return;
+                } catch (final RuntimeException e) {
+                    exception = e;
+                    tries++;
+                }
+            } while (tries < 5);
+            LOG.error("Failed to delete artifact from repository after upload was interrupted", exception);
+        }
     }
 
 }

hawkbit-ui/src/main/java/org/eclipse/hawkbit/ui/artifacts/upload/FileTransferHandlerStreamVariable.java

@@ -10,6 +10,8 @@ package org.eclipse.hawkbit.ui.artifacts.upload;
 
 import java.io.IOException;
 import java.io.OutputStream;
+import java.io.PipedInputStream;
+import java.io.PipedOutputStream;
 
 import org.eclipse.hawkbit.repository.ArtifactManagement;
 import org.eclipse.hawkbit.repository.model.SoftwareModule;
@@ -72,26 +74,28 @@ public class FileTransferHandlerStreamVariable extends AbstractFileTransferHandl
 
     @Override
     public final OutputStream getOutputStream() {
+        if (isUploadInterrupted()) {
+            return ByteStreams.nullOutputStream();
+        }
 
         // we return the outputstream so we cannot close it here
         @SuppressWarnings("squid:S2095")
-        OutputStream outputStream = ByteStreams.nullOutputStream();
+        final PipedOutputStream outputStream = new PipedOutputStream();
+        PipedInputStream inputStream = null;
         try {
-            outputStream = createOutputStreamForTempFile();
+            inputStream = new PipedInputStream(outputStream);
-            publishUploadProgressEvent(fileUploadId, 0, fileSize, getTempFilePath());
+            publishUploadProgressEvent(fileUploadId, 0, fileSize);
-
+            startTransferToRepositoryThread(inputStream, fileUploadId, mimeType);
         } catch (final IOException e) {
-            LOG.error("Creating temp file for upload failed {}.", e);
+            LOG.error("Creating piped Stream failed {}.", e);
-            try {
+            tryToCloseIOStream(outputStream);
-                outputStream.close();
+            tryToCloseIOStream(inputStream);
-            } catch (final IOException e1) {
-                LOG.error("Closing output stream caused an exception {}", e1);
-            }
-
             setFailureReasonUploadFailed();
             setUploadInterrupted();
+            getUploadState().updateFileUploadProgress(fileUploadId,
+                    new FileUploadProgress(fileUploadId, FileUploadStatus.UPLOAD_FAILED));
+            return ByteStreams.nullOutputStream();
         }
-
         return outputStream;
     }
 
@@ -124,7 +128,7 @@ public class FileTransferHandlerStreamVariable extends AbstractFileTransferHandl
             return;
         }
 
-        publishUploadProgressEvent(fileUploadId, event.getBytesReceived(), event.getContentLength(), getTempFilePath());
+        publishUploadProgressEvent(fileUploadId, event.getBytesReceived(), event.getContentLength());
     }
 
     /**
@@ -137,8 +141,6 @@ public class FileTransferHandlerStreamVariable extends AbstractFileTransferHandl
     @Override
     public void streamingFinished(final StreamingEndEvent event) {
         assertStateConsistency(fileUploadId, event.getFileName());
-
-        transferArtifactToRepository(fileUploadId, event.getContentLength(), mimeType, getTempFilePath());
     }
 
     /**
@@ -157,6 +159,7 @@ public class FileTransferHandlerStreamVariable extends AbstractFileTransferHandl
         } else {
             publishUploadFailedEvent(fileUploadId, event.getException());
         }
+        setUploadInterrupted();
         publishUploadFinishedEvent(fileUploadId);
     }
 

hawkbit-ui/src/main/java/org/eclipse/hawkbit/ui/artifacts/upload/FileTransferHandlerVaadinUpload.java

@@ -10,6 +10,8 @@ package org.eclipse.hawkbit.ui.artifacts.upload;
 
 import java.io.IOException;
 import java.io.OutputStream;
+import java.io.PipedInputStream;
+import java.io.PipedOutputStream;
 import java.util.Optional;
 
 import org.eclipse.hawkbit.repository.ArtifactManagement;
@@ -51,7 +53,6 @@ public class FileTransferHandlerVaadinUpload extends AbstractFileTransferHandler
     private final transient SoftwareModuleManagement softwareModuleManagement;
     private final long maxSize;
 
-    private volatile String mimeType;
     private volatile FileUploadId fileUploadId;
 
     FileTransferHandlerVaadinUpload(final long maxSize, final SoftwareModuleManagement softwareManagement,
@@ -70,12 +71,12 @@ public class FileTransferHandlerVaadinUpload extends AbstractFileTransferHandler
     public void uploadStarted(final StartedEvent event) {
         // reset internal state here because instance is reused for next upload!
         resetState();
-        this.mimeType = null;
         this.fileUploadId = null;
 
         assertThatOneSoftwareModuleIsSelected();
 
-        // selected software module at the time of this callback is considered
+        // selected software module at the time of this callback is
+        // considered
         SoftwareModule softwareModule = null;
         final Optional<Long> selectedSoftwareModuleId = getUploadState().getSelectedBaseSwModuleId();
         final Long softwareModuleId = selectedSoftwareModuleId.orElse(null);
@@ -84,7 +85,6 @@ public class FileTransferHandlerVaadinUpload extends AbstractFileTransferHandler
         }
 
         this.fileUploadId = new FileUploadId(event.getFilename(), softwareModule);
-        this.mimeType = event.getMIMEType();
 
         if (getUploadState().isFileInUploadState(this.fileUploadId)) {
             setFailureReasonUploadFailed();
@@ -131,26 +131,23 @@ public class FileTransferHandlerVaadinUpload extends AbstractFileTransferHandler
 
         // we return the outputstream so we cannot close it here
         @SuppressWarnings("squid:S2095")
-        OutputStream outputStream = ByteStreams.nullOutputStream();
+        final PipedOutputStream outputStream = new PipedOutputStream();
+        PipedInputStream inputStream = null;
         try {
-            outputStream = createOutputStreamForTempFile();
+            inputStream = new PipedInputStream(outputStream);
-            this.mimeType = mimeType;
+            publishUploadProgressEvent(fileUploadId, 0, 0);
-            publishUploadProgressEvent(fileUploadId, 0, 0, getTempFilePath());
+            startTransferToRepositoryThread(inputStream, fileUploadId, mimeType);
-
         } catch (final IOException e) {
-            LOG.error("Creating temp file for upload failed {}.", e);
+            LOG.error("Creating piped Stream failed {}.", e);
-            if (outputStream != null) {
+            tryToCloseIOStream(outputStream);
-                try {
+            tryToCloseIOStream(inputStream);
-                    outputStream.close();
-                } catch (final IOException e1) {
-                    LOG.error("Closing output stream caused an exception {}", e1);
-                }
-            }
-
             setFailureReasonUploadFailed();
             setUploadInterrupted();
+            getUploadState().updateFileUploadProgress(fileUploadId,
+                    new FileUploadProgress(fileUploadId, FileUploadStatus.UPLOAD_FAILED));
+            uiNotification.displayWarning("try again");
+            return ByteStreams.nullOutputStream();
         }
-
         return outputStream;
     }
 
@@ -173,7 +170,7 @@ public class FileTransferHandlerVaadinUpload extends AbstractFileTransferHandler
             return;
         }
 
-        publishUploadProgressEvent(fileUploadId, readBytes, contentLength, getTempFilePath());
+        publishUploadProgressEvent(fileUploadId, readBytes, contentLength);
     }
 
     /**
@@ -190,8 +187,6 @@ public class FileTransferHandlerVaadinUpload extends AbstractFileTransferHandler
             return;
         }
         assertStateConsistency(fileUploadId, event.getFilename());
-
-        transferArtifactToRepository(fileUploadId, event.getLength(), mimeType, getTempFilePath());
     }
 
     /**
@@ -220,6 +215,7 @@ public class FileTransferHandlerVaadinUpload extends AbstractFileTransferHandler
         } else {
             publishUploadFailedEvent(fileUploadId, event.getReason());
         }
+        setUploadInterrupted();
         publishUploadFinishedEvent(fileUploadId);
     }
 

hawkbit-ui/src/main/java/org/eclipse/hawkbit/ui/artifacts/upload/FileUploadProgress.java

@@ -75,6 +75,27 @@ public class FileUploadProgress implements Serializable {
         this.fileUploadStatus = fileUploadStatus;
     }
 
+    /**
+     * Creates a new {@link FileUploadProgress} instance.
+     * 
+     * @param fileUploadId
+     *            the {@link FileUploadId} to which this progress information
+     *            belongs.
+     * @param fileUploadStatus
+     *            the {@link FileUploadStatus} of this progress
+     * @param bytesRead
+     *            number of bytes read
+     * @param contentLength
+     *            size of the file in bytes
+     */
+    FileUploadProgress(final FileUploadId fileUploadId, final FileUploadStatus fileUploadStatus,
+            final long bytesRead, final long contentLength) {
+        this.fileUploadId = fileUploadId;
+        this.fileUploadStatus = fileUploadStatus;
+        this.contentLength = contentLength;
+        this.bytesRead = bytesRead;
+    }
+
     /**
      * Creates a new {@link FileUploadProgress} instance.
      * 

hawkbit-ui/src/main/java/org/eclipse/hawkbit/ui/artifacts/upload/UploadDropAreaLayout.java

@@ -10,7 +10,6 @@ package org.eclipse.hawkbit.ui.artifacts.upload;
 
 import javax.servlet.MultipartConfigElement;
 
-import org.apache.commons.lang3.StringUtils;
 import org.eclipse.hawkbit.repository.ArtifactManagement;
 import org.eclipse.hawkbit.repository.SoftwareModuleManagement;
 import org.eclipse.hawkbit.repository.model.SoftwareModule;
@@ -179,39 +178,28 @@ public class UploadDropAreaLayout extends AbstractComponent {
         private void uploadFilesForSoftwareModule(final Html5File[] files, final Long softwareModuleId) {
             final SoftwareModule softwareModule = softwareManagement.get(softwareModuleId).orElse(null);
 
-            boolean isDirectory = false;
+            boolean duplicateFound = false;
-            boolean isDuplicate = false;
 
             for (final Html5File file : files) {
-
+                if (artifactUploadState.isFileInUploadState(file.getFileName(), softwareModule)) {
-                isDirectory = isDirectory(file);
+                    duplicateFound = true;
-                isDuplicate = artifactUploadState.isFileInUploadState(file.getFileName(), softwareModule);
+                } else {
-
-                if (!isDirectory && !isDuplicate) {
                     file.setStreamVariable(new FileTransferHandlerStreamVariable(file.getFileName(), file.getFileSize(),
                             multipartConfigElement.getMaxFileSize(), file.getType(), softwareModule, artifactManagement,
                             i18n));
                 }
             }
-            if (isDirectory && isDuplicate) {
+            if (duplicateFound) {
-                uiNotification.displayValidationError(i18n.getMessage("message.no.duplicateFiles") + "<br>"
+                uiNotification.displayValidationError(
-                        + i18n.getMessage("message.no.directory.upload"));
+                        i18n.getMessage("message.no.duplicateFiles"));
-            } else if (isDirectory) {
-                uiNotification.displayValidationError(i18n.getMessage("message.no.directory.upload"));
-            } else if (isDuplicate) {
-                uiNotification.displayValidationError(i18n.getMessage("message.no.duplicateFiles"));
             }
         }
 
-        private boolean isDirectory(final Html5File file) {
-            return StringUtils.isBlank(file.getType()) && file.getFileSize() % 4096 == 0;
-        }
-
         private boolean validate(final DragAndDropEvent event) {
             // check if drop is valid.If valid ,check if software module is
             // selected.
             if (!isFilesDropped(event)) {
-                uiNotification.displayValidationError(i18n.getMessage(UIMessageIdProvider.MESSAGE_ACTION_NOT_ALLOWED));
+                uiNotification.displayValidationError(i18n.getMessage("message.drop.onlyFiles"));
                 return false;
             }
             return validateSoftwareModuleSelection();

hawkbit-ui/src/main/java/org/eclipse/hawkbit/ui/utils/SpringContextHelper.java

@@ -55,4 +55,19 @@ public final class SpringContextHelper {
         return context.getBean(beanClazz);
     }
 
+    /**
+     * method to return a certain bean by its class and name.
+     * 
+     * @param beanName
+     *            name of the beand which should be returned from the
+     *            application context
+     * @param beanClazz
+     *            class of the bean which should be returned from the
+     *            application context
+     * @return the requested bean
+     */
+    public static <T> T getBean(final String beanName, final Class<T> beanClazz) {
+        return context.getBean(beanName, beanClazz);
+    }
+
 }

hawkbit-ui/src/main/resources/messages.properties

@@ -393,6 +393,7 @@ message.error.missing.tagname = Please select tag name
 message.type.delete = Please unclick the distribution type {0}, then try to delete
 message.error.dist.set.type.update= Distribution set type is already assigned to set(s) and cannot be changed
 message.no.directory.upload = Directory upload is not supported
+message.drop.onlyFiles = Please drop files only
 message.delete.filter.confirm = Are you sure you want to delete custom filter?
 message.delete.filter.success = Custom filter {0} deleted Successfully!
 message.create.filter.success = Custom filter {0} created Successfully!