in coordinator db polling for available segments, ignore corrupted entries in segments table so that coordinator continues to load new segments even if there are few corrupted segment entries

server/src/main/java/io/druid/metadata/SQLMetadataSegmentManager.java

@@ -20,8 +20,10 @@
 package io.druid.metadata;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.google.common.base.Predicates;
 import com.google.common.base.Supplier;
 import com.google.common.base.Throwables;
+import com.google.common.collect.Collections2;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Ordering;
@@ -431,7 +433,7 @@ public class SQLMetadataSegmentManager implements MetadataSegmentManager
 
       log.debug("Starting polling of segment table");
 
-      List<DataSegment> segments = dbi.withHandle(
+      final List<DataSegment> segments = dbi.withHandle(
           new HandleCallback<List<DataSegment>>()
           {
             @Override
@@ -451,7 +453,8 @@ public class SQLMetadataSegmentManager implements MetadataSegmentManager
                                      return jsonMapper.readValue(r.getBytes("payload"), DataSegment.class);
                                    }
                                    catch (IOException e) {
-                                     throw new SQLException(e);
+                                     log.makeAlert(e, "Failed to read segment from db.");
+                                     return null;
                                    }
                                  }
                                }
@@ -466,9 +469,13 @@ public class SQLMetadataSegmentManager implements MetadataSegmentManager
         return;
       }
 
+      final Collection<DataSegment> segmentsFinal = Collections2.filter(
+          segments, Predicates.notNull()
+      );
+
       log.info("Polled and found %,d segments in the database", segments.size());
 
-      for (final DataSegment segment : segments) {
+      for (final DataSegment segment : segmentsFinal) {
         String datasourceName = segment.getDataSource();
 
         DruidDataSource dataSource = newDataSources.get(datasourceName);

server/src/main/java/io/druid/metadata/SQLMetadataSegmentPublisher.java

@@ -22,6 +22,7 @@
 package io.druid.metadata;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.google.common.annotations.VisibleForTesting;
 import com.google.inject.Inject;
 import com.metamx.common.logger.Logger;
 import io.druid.timeline.DataSegment;
@@ -63,6 +64,32 @@ public class SQLMetadataSegmentPublisher implements MetadataSegmentPublisher
 
   @Override
   public void publishSegment(final DataSegment segment) throws IOException
+  {
+    publishSegment(
+        segment.getIdentifier(),
+        segment.getDataSource(),
+        new DateTime().toString(),
+        segment.getInterval().getStart().toString(),
+        segment.getInterval().getEnd().toString(),
+        (segment.getShardSpec() instanceof NoneShardSpec) ? false : true,
+        segment.getVersion(),
+        true,
+        jsonMapper.writeValueAsBytes(segment)
+    );
+  }
+
+  @VisibleForTesting
+  void publishSegment(
+      final String identifier,
+      final String dataSource,
+      final String createdDate,
+      final String start,
+      final String end,
+      final boolean partitioned,
+      final String version,
+      final boolean used,
+      final byte[] payload
+  )
   {
     try {
       final DBI dbi = connector.getDBI();
@@ -75,14 +102,14 @@ public class SQLMetadataSegmentPublisher implements MetadataSegmentPublisher
               return handle.createQuery(
                   String.format("SELECT id FROM %s WHERE id=:id", config.getSegmentsTable())
               )
-                           .bind("id", segment.getIdentifier())
+                           .bind("id", identifier)
                            .list();
             }
           }
       );
 
       if (!exists.isEmpty()) {
-        log.info("Found [%s] in DB, not updating DB", segment.getIdentifier());
+        log.info("Found [%s] in DB, not updating DB", identifier);
         return;
       }
 
@@ -93,15 +120,15 @@ public class SQLMetadataSegmentPublisher implements MetadataSegmentPublisher
             public Void withHandle(Handle handle) throws Exception
             {
               handle.createStatement(statement)
-                    .bind("id", segment.getIdentifier())
-                    .bind("dataSource", segment.getDataSource())
-                    .bind("created_date", new DateTime().toString())
-                    .bind("start", segment.getInterval().getStart().toString())
-                    .bind("end", segment.getInterval().getEnd().toString())
-                    .bind("partitioned", (segment.getShardSpec() instanceof NoneShardSpec) ? false : true)
-                    .bind("version", segment.getVersion())
-                    .bind("used", true)
-                    .bind("payload", jsonMapper.writeValueAsBytes(segment))
+                    .bind("id", identifier)
+                    .bind("dataSource", dataSource)
+                    .bind("created_date", createdDate)
+                    .bind("start", start)
+                    .bind("end", end)
+                    .bind("partitioned", partitioned)
+                    .bind("version", version)
+                    .bind("used", used)
+                    .bind("payload", payload)
                     .execute();
 
               return null;

server/src/test/java/io/druid/metadata/MetadataSegmentManagerTest.java

@@ -24,7 +24,10 @@ import com.google.common.base.Suppliers;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Iterables;
+import com.metamx.emitter.EmittingLogger;
 import io.druid.jackson.DefaultObjectMapper;
+import io.druid.server.metrics.NoopServiceEmitter;
 import io.druid.timeline.DataSegment;
 import io.druid.timeline.partition.NoneShardSpec;
 import org.joda.time.Interval;
@@ -40,6 +43,7 @@ public class MetadataSegmentManagerTest
   public final TestDerbyConnector.DerbyConnectorRule derbyConnectorRule = new TestDerbyConnector.DerbyConnectorRule();
 
   private SQLMetadataSegmentManager manager;
+  private SQLMetadataSegmentPublisher publisher;
   private final ObjectMapper jsonMapper = new DefaultObjectMapper();
 
   private final DataSegment segment1 = new DataSegment(
@@ -78,7 +82,6 @@ public class MetadataSegmentManagerTest
   public void setUp() throws Exception
   {
     TestDerbyConnector connector = derbyConnectorRule.getConnector();
-
     manager = new SQLMetadataSegmentManager(
         jsonMapper,
         Suppliers.ofInstance(new MetadataSegmentManagerConfig()),
@@ -86,7 +89,7 @@ public class MetadataSegmentManagerTest
         connector
     );
 
-    SQLMetadataSegmentPublisher publisher = new SQLMetadataSegmentPublisher(
+    publisher = new SQLMetadataSegmentPublisher(
         jsonMapper,
         derbyConnectorRule.metadataTablesConfigSupplier().get(),
         connector
@@ -114,6 +117,33 @@ public class MetadataSegmentManagerTest
     manager.stop();
   }
 
+  @Test
+  public void testPollWithCurroptedSegment()
+  {
+    //create a corrupted segment entry in segments table, which tests
+    //that overall loading of segments from database continues to work
+    //even in one of the entries are corrupted.
+    publisher.publishSegment(
+        "corrupt-segment-id",
+        "corrupt-datasource",
+        "corrupt-create-date",
+        "corrupt-start-date",
+        "corrupt-end-date",
+        true,
+        "corrupt-version",
+        true,
+        "corrupt-payload".getBytes()
+    );
+
+    EmittingLogger.registerEmitter(new NoopServiceEmitter());
+    manager.start();
+    manager.poll();
+
+    Assert.assertEquals(
+        "wikipedia", Iterables.getOnlyElement(manager.getInventory()).getName()
+    );
+  }
+
   @Test
   public void testGetUnusedSegmentsForInterval() throws Exception
   {