GUACAMOLE-926: Merge disabling of batch executor for SQL Server.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/JDBCAuthenticationProviderModule.java

@@ -127,7 +127,8 @@ public class JDBCAuthenticationProviderModule extends MyBatisModule {
         // Transaction factory
         bindTransactionFactoryType(JdbcTransactionFactory.class);
         
-        // Set the JDBC Auth provider to use batch execution when possible
+        // Set the JDBC Auth provider to use batch execution if enabled
+        if (environment.shouldUseBatchExecutor())
             bindConfigurationSetting(configuration -> {
                 configuration.setDefaultExecutorType(ExecutorType.BATCH);
             });

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/JDBCEnvironment.java

@@ -254,4 +254,22 @@ public abstract class JDBCEnvironment extends DelegatingEnvironment {
      */
     public abstract boolean enforceAccessWindowsForActiveSessions() throws GuacamoleException;
 
+    /**
+     * Returns true if the JDBC batch executor should be used by default, false
+     * otherwise. The batch executor allows repeated updates to be batched
+     * together for improved performance. 
+     * See https://mybatis.org/mybatis-3/java-api.html#sqlSessions
+     *
+     * @return
+     *     true if the batch executor should be used by default, false otherwise.
+     */
+    public boolean shouldUseBatchExecutor() {
+
+        // Unless otherwise overwritten due to implementation-specific problems,
+        // all JDBC extensions should use the batch executor if possible to
+        // ensure the best performance for repetitive queries
+        return true;
+
+    }
+
 }

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-sqlserver/src/main/java/org/apache/guacamole/auth/sqlserver/SQLServerAuthenticationProviderModule.java

@@ -77,6 +77,10 @@ public class SQLServerAuthenticationProviderModule implements Module {
         // Use UTF-8 in database
         driverProperties.setProperty("characterEncoding", "UTF-8");
 
+        // Trust unknown server certificates if configured to do so
+        if (environment.trustAllServerCertificates())
+            driverProperties.setProperty("trustServerCertificate", "true");
+        
         // Retrieve instance name and set it
         String instance = environment.getSQLServerInstance();
         if (instance != null)

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-sqlserver/src/main/java/org/apache/guacamole/auth/sqlserver/conf/SQLServerEnvironment.java

@@ -295,4 +295,36 @@ public class SQLServerEnvironment extends JDBCEnvironment {
                 true);
     }
 
+    @Override
+    public boolean shouldUseBatchExecutor() {
+
+        // The SQL Server driver does not work when batch execution is enabled.
+        // Specifically, inserts fail with com.microsoft.sqlserver.jdbc.SQLServerException:
+        // The statement must be executed before any results can be obtained.
+        // See https://github.com/microsoft/mssql-jdbc/issues/358 for more.
+        logger.warn(
+                "JDBC batch executor is disabled for SQL Server Connections. "
+                + "Large batched updates may run slower."
+        );
+        return false;
+        
+    }
+
+    /**
+     * Returns true if all server certificates should be trusted, including
+     * those signed by an unknown certificate authority, such as self-signed
+     * certificates, or false otherwise.
+     *
+     * @throws GuacamoleException
+     *     If an error occurs while retrieving the property value, or if the
+     *     value was not set, as this property is required.
+     */
+    public boolean trustAllServerCertificates() throws GuacamoleException {
+
+        // Do not trust unknown certificates unless explicitly enabled
+        return getProperty(
+                SQLServerGuacamoleProperties.SQLSERVER_TRUST_ALL_SERVER_CERTIFICATES,
+                false);
+    }
+
 }

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-sqlserver/src/main/java/org/apache/guacamole/auth/sqlserver/conf/SQLServerGuacamoleProperties.java

@@ -245,4 +245,17 @@ public class SQLServerGuacamoleProperties {
 
     };
 
+    /**
+     * Whether or not all server certificates should be trusted, including those
+     * signed by an unknown certificate authority, such as self-signed
+     * certificates.
+     */
+    public static final BooleanGuacamoleProperty SQLSERVER_TRUST_ALL_SERVER_CERTIFICATES =
+            new BooleanGuacamoleProperty() {
+
+        @Override
+        public String getName() { return "sqlserver-trust-all-server-certificates"; }
+
+    };
+
 }