[Broker Clean up] Decouple broker from transport package (apache#3105)

Change BrokerRequestHandler to an interface
Move all transport package related classes into ConnectionPoolBrokerRequestHandler implementation
Enhancing broker query log to include servers and exceptions info

Query log example:
2018/08/22 16:53:53.816 INFO [com.linkedin.pinot.broker.requesthandler.ConnectionPoolBrokerRequestHandler] [] Request 7 ScatterGatherStats: <hostName>_O=0,0,0,62
2018/08/22 16:53:53.816 INFO [com.linkedin.pinot.broker.requesthandler.BaseBrokerRequestHandler] [] Request 7:myTable_OFFLINE, time:100ms, docs:10000/44673408, entries:0/80000, servers:1/1, exceptions:0, query:select * from myTable limit 10000

Explaination: first line is the ScatterGatherStats, second line includes tableName, queryTime, numDocsScanned/numTotalDocs, numEntriesScannedIn/PostFilter, serverResponded/Queried, numExceptions, query

pinot-broker/src/main/java/com/linkedin/pinot/broker/api/resources/PinotBrokerDebug.java

@@ -15,7 +15,7 @@
  */
 package com.linkedin.pinot.broker.api.resources;
 
-import com.linkedin.pinot.broker.requesthandler.BrokerRequestHandler;
+import com.linkedin.pinot.broker.routing.RoutingTable;
 import com.linkedin.pinot.broker.routing.TimeBoundaryService;
 import com.linkedin.pinot.common.config.TableNameBuilder;
 import com.linkedin.pinot.common.metrics.BrokerMeter;
@@ -44,13 +44,13 @@ public class PinotBrokerDebug {
   private static final Logger LOGGER = LoggerFactory.getLogger(PinotBrokerDebug.class);
 
   @Inject
-  private BrokerRequestHandler requestHandler;
+  private RoutingTable _routingTable;
 
   @Inject
-  private BrokerMetrics brokerMetrics;
+  private BrokerMetrics _brokerMetrics;
 
   @Inject
-  private TimeBoundaryService timeBoundaryService;
+  private TimeBoundaryService _timeBoundaryService;
 
   @GET
   @Produces(MediaType.APPLICATION_JSON)
@@ -61,13 +61,13 @@ public class PinotBrokerDebug {
       @ApiResponse(code = 500, message = "Internal server error")
   })
   public String debugRoutingTable(
-      @ApiParam(value = "Name of the table", required = false) @PathParam("tableName") String tableName
+      @ApiParam(value = "Name of the table") @PathParam("tableName") String tableName
   ) {
     try {
-      return requestHandler.getRoutingTableSnapshot(tableName);
+      return _routingTable.dumpSnapshot(tableName);
     } catch (Exception e) {
       LOGGER.error("Caught exception while processing GET request", e);
-      brokerMetrics.addMeteredGlobalValue(BrokerMeter.UNCAUGHT_GET_EXCEPTIONS, 1);
+      _brokerMetrics.addMeteredGlobalValue(BrokerMeter.UNCAUGHT_GET_EXCEPTIONS, 1);
       throw new WebApplicationException(e, Response.Status.INTERNAL_SERVER_ERROR);
     }
   }
@@ -81,7 +81,7 @@ public String debugRoutingTable(
       @ApiResponse(code = 500, message = "Internal server error")
   })
   public String debugTimeBoundaryService(
-      @ApiParam(value = "Name of the table", required = false) @PathParam("tableName") String tableName
+      @ApiParam(value = "Name of the table") @PathParam("tableName") String tableName
   ) {
     try {
       String response = "{}";
@@ -90,15 +90,15 @@ public String debugTimeBoundaryService(
         if (tableType == null) {
           tableName = TableNameBuilder.OFFLINE.tableNameWithType(tableName);
         }
-        TimeBoundaryService.TimeBoundaryInfo tbInfo = timeBoundaryService.getTimeBoundaryInfoFor(tableName);
+        TimeBoundaryService.TimeBoundaryInfo tbInfo = _timeBoundaryService.getTimeBoundaryInfoFor(tableName);
         if (tbInfo != null) {
           response = tbInfo.toJsonString();
         }
       }
       return response;
     } catch (Exception e) {
       LOGGER.error("Caught exception while processing GET request", e);
-      brokerMetrics.addMeteredGlobalValue(BrokerMeter.UNCAUGHT_GET_EXCEPTIONS, 1);
+      _brokerMetrics.addMeteredGlobalValue(BrokerMeter.UNCAUGHT_GET_EXCEPTIONS, 1);
       throw new WebApplicationException(e, Response.Status.INTERNAL_SERVER_ERROR);
     }
   }

pinot-broker/src/main/java/com/linkedin/pinot/broker/broker/BrokerAdminApiApplication.java

@@ -17,6 +17,7 @@
 
 import com.google.common.base.Preconditions;
 import com.linkedin.pinot.broker.requesthandler.BrokerRequestHandler;
+import com.linkedin.pinot.broker.routing.RoutingTable;
 import com.linkedin.pinot.broker.routing.TimeBoundaryService;
 import com.linkedin.pinot.common.metrics.BrokerMetrics;
 import io.swagger.jaxrs.config.BeanConfig;
@@ -37,16 +38,16 @@ public class BrokerAdminApiApplication extends ResourceConfig {
   private URI _baseUri;
   private HttpServer _httpServer;
 
-  public BrokerAdminApiApplication(final BrokerServerBuilder brokerServerBuilder, final BrokerMetrics brokerMetrics,
-      final BrokerRequestHandler brokerRequestHandler, final TimeBoundaryService timeBoundaryService) {
+  public BrokerAdminApiApplication(BrokerServerBuilder brokerServerBuilder) {
     packages(RESOURCE_PACKAGE);
     register(new AbstractBinder() {
       @Override
       protected void configure() {
         bind(brokerServerBuilder).to(BrokerServerBuilder.class);
-        bind(brokerMetrics).to(BrokerMetrics.class);
-        bind(brokerRequestHandler).to(BrokerRequestHandler.class);
-        bind(timeBoundaryService).to(TimeBoundaryService.class);
+        bind(brokerServerBuilder.getRoutingTable()).to(RoutingTable.class);
+        bind(brokerServerBuilder.getTimeBoundaryService()).to(TimeBoundaryService.class);
+        bind(brokerServerBuilder.getBrokerMetrics()).to(BrokerMetrics.class);
+        bind(brokerServerBuilder.getBrokerRequestHandler()).to(BrokerRequestHandler.class);
       }
     });
     registerClasses(io.swagger.jaxrs.listing.ApiListingResource.class);