for #1205, Get connection sync to prevent dead lock for sharding-proxy

apache · Sep 19, 2018 · 23db595 · 23db595
1 parent f38351a
commit 23db595
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Showing 4 changed files with 35 additions and 13 deletions.
diff --git a/...roxy/src/main/java/io/shardingsphere/proxy/backend/jdbc/connection/BackendConnection.java b/...roxy/src/main/java/io/shardingsphere/proxy/backend/jdbc/connection/BackendConnection.java
@@ -37,6 +37,7 @@
 import java.sql.Statement;
 import java.util.Collection;
 import java.util.LinkedList;
+import java.util.List;
 import java.util.concurrent.CopyOnWriteArrayList;
 
 /**
@@ -58,18 +59,19 @@ public final class BackendConnection implements AutoCloseable {
     private final Collection<ResultSet> cachedResultSets = new CopyOnWriteArrayList<>();
 
     /**
-     * Get connection of current thread datasource.
+     * Get connections of current thread datasource.
      *
      * @param dataSourceName data source name
+     * @param connectionSize size of connections to be get
      * @return connection
      * @throws SQLException SQL exception
      */
-    public Connection getConnection(final String dataSourceName) throws SQLException {
+    public List<Connection> getConnections(final String dataSourceName, final int connectionSize) throws SQLException {
         try {
             ShardingEventBusInstance.getInstance().post(new GetConnectionStartEvent(dataSourceName));
-            Connection result = ruleRegistry.getBackendDataSource().getConnection(dataSourceName);
-            cachedConnections.add(result);
-            GetConnectionEvent finishEvent = new GetConnectionFinishEvent(DataSourceMetaDataFactory.newInstance(DatabaseType.MySQL, result.getMetaData().getURL()));
+            List<Connection> result = ruleRegistry.getBackendDataSource().getConnections(dataSourceName, connectionSize);
+            cachedConnections.addAll(result);
+            GetConnectionEvent finishEvent = new GetConnectionFinishEvent(DataSourceMetaDataFactory.newInstance(DatabaseType.MySQL, result.get(0).getMetaData().getURL()));
             finishEvent.setExecuteSuccess();
             ShardingEventBusInstance.getInstance().post(finishEvent);
             return result;

diff --git a/.../src/main/java/io/shardingsphere/proxy/backend/jdbc/datasource/JDBCBackendDataSource.java b/.../src/main/java/io/shardingsphere/proxy/backend/jdbc/datasource/JDBCBackendDataSource.java
@@ -30,7 +30,9 @@
 import java.lang.reflect.Method;
 import java.sql.Connection;
 import java.sql.SQLException;
+import java.util.ArrayList;
 import java.util.LinkedHashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 
@@ -91,7 +93,27 @@ private JDBCBackendDataSourceFactory getBackendDataSourceFactory(final Transacti
      * @throws SQLException SQL exception
      */
     public Connection getConnection(final String dataSourceName) throws SQLException {
-        return getDataSourceMap().get(dataSourceName).getConnection();
+        return getConnections(dataSourceName, 1).get(0);
+    }
+
+    /**
+     * Get connections.
+     *
+     * @param dataSourceName data source name
+     * @param connectionSize size of connections to be get
+     * @return connections
+     * @throws SQLException SQL exception
+     */
+    @SuppressWarnings("SynchronizationOnLocalVariableOrMethodParameter")
+    public List<Connection> getConnections(final String dataSourceName, final int connectionSize) throws SQLException {
+        List<Connection> result = new ArrayList<>(connectionSize);
+        DataSource dataSource = getDataSourceMap().get(dataSourceName);
+        synchronized (dataSource) {
+            for (int i = 0; i < connectionSize; i++) {
+                result.add(dataSource.getConnection());
+            }
+        }
+        return result;
     }
 
     private Map<String, DataSource> getDataSourceMap() {

diff --git a/...g-proxy/src/main/java/io/shardingsphere/proxy/backend/jdbc/execute/JDBCExecuteEngine.java b/...g-proxy/src/main/java/io/shardingsphere/proxy/backend/jdbc/execute/JDBCExecuteEngine.java
@@ -61,7 +61,6 @@
 import java.sql.SQLException;
 import java.sql.Statement;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
@@ -109,10 +108,10 @@ public ExecuteResponse execute(final SQLRouteResult routeResult) throws SQLExcep
         boolean isExceptionThrown = ExecutorExceptionHandler.isExceptionThrown();
         Map<String, Object> dataMap = ExecutorDataMap.getDataMap();
         Collection<ShardingExecuteGroup<StatementExecuteUnit>> sqlExecuteGroups =
-                sqlExecutePrepareTemplate.getExecuteUnitGroups(routeResult.getRouteUnits(), new JDBCExecuteEngine.ConnectionStrictlySQLExecutePrepareCallback(isReturnGeneratedKeys));
+                sqlExecutePrepareTemplate.getExecuteUnitGroups(routeResult.getRouteUnits(), new ConnectionStrictlySQLExecutePrepareCallback(isReturnGeneratedKeys));
         Collection<ExecuteResponseUnit> executeResponseUnits = sqlExecuteTemplate.executeGroup((Collection) sqlExecuteGroups,
-                new JDBCExecuteEngine.FirstConnectionStrictlySQLExecuteCallback(sqlType, isExceptionThrown, dataMap, isReturnGeneratedKeys),
-                new JDBCExecuteEngine.ConnectionStrictlySQLExecuteCallback(sqlType, isExceptionThrown, dataMap, isReturnGeneratedKeys));
+                new FirstConnectionStrictlySQLExecuteCallback(sqlType, isExceptionThrown, dataMap, isReturnGeneratedKeys),
+                new ConnectionStrictlySQLExecuteCallback(sqlType, isExceptionThrown, dataMap, isReturnGeneratedKeys));
         ExecuteResponseUnit firstExecuteResponseUnit = executeResponseUnits.iterator().next();
         return firstExecuteResponseUnit instanceof ExecuteQueryResponseUnit
                 ? getExecuteQueryResponse(((ExecuteQueryResponseUnit) firstExecuteResponseUnit).getQueryResponsePackets(), executeResponseUnits) : new ExecuteUpdateResponse(executeResponseUnits);
@@ -177,7 +176,7 @@ private final class ConnectionStrictlySQLExecutePrepareCallback implements SQLEx
 
         @Override
         public List<Connection> getConnections(final String dataSourceName, final int connectionSize) throws SQLException {
-            return Collections.singletonList(getBackendConnection().getConnection(dataSourceName));
+            return getBackendConnection().getConnections(dataSourceName, connectionSize);
         }
 
         @Override

diff --git a/sharding-proxy/src/main/resources/conf/server.yaml b/sharding-proxy/src/main/resources/conf/server.yaml
@@ -21,8 +21,7 @@
 #
 #  # CONNECTION_STRICTLY: Proxy will release connections after get the overall rows from the ResultSet.
 #  #                      Meanwhile, the cost of the memory will be increased.
-#  connection.mode: CONNECTION_STRICTLY
-#  max.connections.size.per.query: 4
+#  max.connections.size.per.query: 1
 #  acceptor.size: 16  # The default value is available processors count * 2.
 #  executor.size: 16  # Infinite by default.
 #  proxy.transaction.enabled: false