Added test case to retrieve server timezone

sink-connector-lightweight/src/test/java/com/altinity/clickhouse/debezium/embedded/ddl/parser/CreateTableDataTypesTimeZoneIT.java

@@ -81,10 +81,6 @@ public void testCreateTable() throws Exception {
         BaseDbWriter writer = new BaseDbWriter(clickHouseContainer.getHost(), clickHouseContainer.getFirstMappedPort(),
                 "employees", clickHouseContainer.getUsername(), clickHouseContainer.getPassword(), null);
 
-        ResultSet clickHouseTimeZone = writer.executeQueryWithResultSet("select timezone()");
-        while(clickHouseTimeZone.next()) {
-            clickHouseTimeZone.getString(1).equalsIgnoreCase("America/Chicago");
-        }
         Map<String, String> decimalTable = writer.getColumnsDataTypesForTable("numeric_types_DECIMAL_65_30");
         Map<String, String> dateTimeTable = writer.getColumnsDataTypesForTable("temporal_types_DATETIME6");
         Map<String, String> timestampTable = writer.getColumnsDataTypesForTable("temporal_types_TIMESTAMP6");

sink-connector/src/main/java/com/altinity/clickhouse/sink/connector/db/DBMetadata.java

@@ -11,6 +11,8 @@
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.sql.Statement;
+import java.time.ZoneId;
+import java.util.TimeZone;
 
 public class DBMetadata {
 
@@ -257,4 +259,20 @@ public boolean checkIfNewReplacingMergeTree(String currentClickHouseVersion) thr
 
         return result;
     }
+
+
+    /**
+     * Function to get the ClickHouse server timezone(Defaults to UTC)
+     */
+    public ZoneId getServerTimeZone(ClickHouseConnection conn) {
+        ZoneId result = ZoneId.of("UTC");
+        if(conn != null) {
+            TimeZone serverTimeZone = conn.getServerTimeZone();
+            if(serverTimeZone != null) {
+                result = serverTimeZone.toZoneId();
+            }
+        }
+
+        return result;
+    }
 }

sink-connector/src/test/java/com/altinity/clickhouse/sink/connector/db/DBMetadataTest.java

@@ -10,7 +10,10 @@
 import org.testcontainers.junit.jupiter.Testcontainers;
 import com.altinity.clickhouse.sink.connector.ClickHouseSinkConnectorConfig;
 import org.apache.commons.lang3.tuple.MutablePair;
+import org.testcontainers.utility.MountableFile;
+
 import java.sql.SQLException;
+import java.time.ZoneId;
 import java.util.HashMap;
 
 @Testcontainers
@@ -19,7 +22,8 @@ public class DBMetadataTest {
 
     @Container
     private ClickHouseContainer clickHouseContainer = new ClickHouseContainer("clickhouse/clickhouse-server:latest")
-            .withInitScript("./init_clickhouse.sql");
+            .withInitScript("./init_clickhouse.sql").withCopyFileToContainer(MountableFile.forClasspathResource("config.xml"), "/etc/clickhouse-server/config.d/config.xml");
+
     @Test
     public void testGetSignColumnForCollapsingMergeTree() {
 
@@ -112,4 +116,20 @@ public void testIsRMTVersionSupported(String clickhouseVersion, boolean result)
         Assert.assertTrue(new DBMetadata().checkIfNewReplacingMergeTree(clickhouseVersion) == result);
     }
 
+    @Test
+    public void getTestGetServerTimeZone() {
+        String dbHostName = clickHouseContainer.getHost();
+        Integer port = clickHouseContainer.getFirstMappedPort();
+        String database = "default";
+        String userName = clickHouseContainer.getUsername();
+        String password = clickHouseContainer.getPassword();
+        String tableName = "employees";
+
+        DbWriter writer = new DbWriter(dbHostName, port, database, tableName, userName, password,
+                new ClickHouseSinkConnectorConfig(new HashMap<>()), null);
+        ZoneId serverTimeZone = new DBMetadata().getServerTimeZone(writer.getConnection());
+
+        Assert.assertTrue(serverTimeZone.toString().equalsIgnoreCase("America/Chicago"));
+
+    }
 }

sink-connector/src/test/resources/config.xml

@@ -0,0 +1,11 @@
+<clickhouse replace="true">
+    <user_directories>
+        <users_xml>
+            <path>users.xml</path>
+        </users_xml>
+        <local_directory>
+            <path>/var/lib/clickhouse/access/</path>
+        </local_directory>
+    </user_directories>
+    <timezone>America/Chicago</timezone>
+</clickhouse>