enhacement: prevent UI freezing with large messages and single messages downloading

client/src/components/Table/Table.jsx

@@ -288,7 +288,7 @@ class Table extends Component {
   }
 
   renderActions(row) {
-    const { actions, onAdd, onDetails, onConfig, onDelete, onEdit, onRestart, onShare, idCol } = this.props;
+    const { actions, onAdd, onDetails, onConfig, onDelete, onEdit, onRestart, onShare, onDownload, idCol } = this.props;
 
     let idColVal = idCol ? row[this.props.idCol] : row.id;
 
@@ -374,6 +374,18 @@ class Table extends Component {
             </span>
             </td>
         )}
+        {actions.find(el => el === constants.TABLE_DOWNLOAD) && (
+            <td className="khq-row-action khq-row-action-main action-hover">
+            <span title="Download"
+                id="download"
+                onClick={() => {
+                  onDownload && onDownload(row);
+                }}
+            >
+              <i className="fa fa-download" />
+            </span>
+            </td>
+        )}
       </>
     );
   }

client/src/containers/Topic/Topic/TopicData/TopicData.jsx

@@ -64,7 +64,8 @@ class TopicData extends Root {
     roles: JSON.parse(sessionStorage.getItem('roles')),
     canDeleteRecords: false,
     percent: 0,
-    loading: true
+    loading: true,
+    canDownload: false
   };
 
   searchFilterTypes = [
@@ -113,6 +114,7 @@ class TopicData extends Root {
         () => {
             if(query.get('single') !== null) {
               this._getSingleMessage(query.get('partition'), query.get('offset'));
+              this.setState({ canDownload: true })
             } else {
               this._getMessages();
             }
@@ -346,10 +348,23 @@ class TopicData extends Root {
       console.error('Failed to copy: ', err);
     }
 
+    this.setState({ canDownload: true })
+
     this.props.history.push(pathToShare)
     this._getSingleMessage(row.partition, row.offset);
   }
 
+  _handleDownload({ key, value: data }) {
+    const hasKey = key && key !== null && key !== 'null';
+
+    const a = document.createElement('a');
+    a.href = URL.createObjectURL( new Blob([data], { type:'text/json' }) );
+    a.download = `${hasKey ? key : 'file'}.json`;
+
+    a.click();
+    a.remove();
+  }
+
   _showDeleteModal = deleteMessage => {
     this.setState({ showDeleteModal: true, deleteMessage });
   };
@@ -642,9 +657,14 @@ class TopicData extends Root {
       datetime,
       isSearching,
       canDeleteRecords,
+      canDownload,
       percent,
       loading
     } = this.state;
+
+    let actions = canDeleteRecords ? [constants.TABLE_DELETE, constants.TABLE_SHARE] : [constants.TABLE_SHARE]
+    if (canDownload) actions.push(constants.TABLE_DOWNLOAD)
+
     let date = moment(datetime);
     const { history } = this.props;
     const firstColumns = [
@@ -965,7 +985,10 @@ class TopicData extends Root {
                 onShare={row => {
                   this._handleOnShare(row);
                 }}
-                actions={canDeleteRecords ? [constants.TABLE_DELETE, constants.TABLE_SHARE] : [constants.TABLE_SHARE]}
+                onDownload={row => {
+                  this._handleDownload(row);
+                }}
+                actions={actions}
                 onExpand={obj => {
                   return Object.keys(obj.headers).map(header => {
                     return (

client/src/utils/constants.js

@@ -24,6 +24,7 @@ export const TABLE_DETAILS = 'details';
 export const TABLE_CONFIG = 'config';
 export const TABLE_RESTART = 'restart';
 export const TABLE_SHARE = 'share';
+export const TABLE_DOWNLOAD = 'download'
 
 // Tab names/route names
 export const CLUSTER = 'cluster';
@@ -65,6 +66,7 @@ export default {
   TABLE_CONFIG,
   TABLE_RESTART,
   TABLE_SHARE,
+  TABLE_DOWNLOAD,
   CLUSTER,
   NODE,
   TOPIC,

src/main/java/org/akhq/models/Record.java

@@ -8,6 +8,7 @@
 import io.confluent.kafka.schemaregistry.client.SchemaRegistryClient;
 import io.confluent.kafka.schemaregistry.json.JsonSchema;
 import io.confluent.kafka.schemaregistry.protobuf.ProtobufSchema;
+import io.micronaut.context.annotation.Value;
 import kafka.coordinator.group.GroupMetadataManager;
 import kafka.coordinator.transaction.TransactionLog;
 import kafka.coordinator.transaction.TxnKey;
@@ -71,6 +72,7 @@ public class Record {
     private byte[] bytesValue;
 
     @Getter(AccessLevel.NONE)
+    @Setter(AccessLevel.NONE)
     private String value;
 
     private final List<String> exceptions = new ArrayList<>();
@@ -145,6 +147,10 @@ public String getValue() {
         return this.value;
     }
 
+    public void setValue(String value) {
+        this.value = value;
+    }
+
     private String convertToString(byte[] payload, Integer schemaId, boolean isKey) {
         if (payload == null) {
             return null;

src/main/java/org/akhq/repositories/RecordRepository.java

@@ -33,6 +33,7 @@
 import org.apache.kafka.common.header.internals.RecordHeader;
 import org.codehaus.httpcache4j.uri.URIBuilder;
 
+import java.nio.charset.StandardCharsets;
 import java.util.*;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ExecutionException;
@@ -76,6 +77,8 @@ public class RecordRepository extends AbstractRepository {
     @Value("${akhq.clients-defaults.consumer.properties.max.poll.records:50}")
     protected int maxPollRecords;
 
+    private final int maxKafkaMessageLength = 1000000; // 1MB
+
     public Map<String, Record> getLastRecord(String clusterId, List<String> topicsName) throws ExecutionException, InterruptedException {
         Map<String, Topic> topics = topicRepository.findByName(clusterId, topicsName).stream()
             .collect(Collectors.toMap(Topic::getName, Function.identity()));
@@ -153,6 +156,7 @@ private List<Record> consumeOldest(Topic topic, Options options) {
             for (ConsumerRecord<byte[], byte[]> record : records) {
                 Record current = newRecord(record, options, topic);
                 if (searchFilter(options, current)) {
+                    filterMessageLength(current);
                     list.add(current);
                 }
             }
@@ -311,6 +315,7 @@ private List<Record> consumeNewest(Topic topic, Options options) {
                         }
                         Record current = newRecord(record, options, topic);
                         if (searchFilter(options, current)) {
+                            filterMessageLength(current);
                             list.add(current);
                         }
                     }
@@ -1268,5 +1273,14 @@ private static class EndOffsetBound {
         private final long end;
         private final KafkaConsumer<byte[], byte[]> consumer;
     }
+
+    private void filterMessageLength(Record record) {
+        int bytesLength = record.getValue().getBytes(StandardCharsets.UTF_8).length;
+        if (bytesLength > maxKafkaMessageLength) {
+            int substringChars = maxKafkaMessageLength / 1000;
+            record.setValue(record.getValue().substring(0, substringChars) +
+                "\n ... Too long message. Full body in share button.");
+        }
+    }
 }