Cassandra 2.5.0 to SQL migration

application/src/main/java/org/thingsboard/server/install/ThingsboardInstallService.java

@@ -28,6 +28,7 @@ import org.thingsboard.server.service.install.DatabaseEntitiesUpgradeService;
 import org.thingsboard.server.service.install.EntityDatabaseSchemaService;
 import org.thingsboard.server.service.install.SystemDataLoaderService;
 import org.thingsboard.server.service.install.TsDatabaseSchemaService;
+import org.thingsboard.server.service.install.migrate.EntitiesMigrateService;
 import org.thingsboard.server.service.install.update.DataUpdateService;
 
 @Service
@@ -68,11 +69,20 @@ public class ThingsboardInstallService {
     @Autowired
     private DataUpdateService dataUpdateService;
 
+    @Autowired(required = false)
+    private EntitiesMigrateService entitiesMigrateService;
+
     public void performInstall() {
         try {
             if (isUpgrade) {
                 log.info("Starting ThingsBoard Upgrade from version {} ...", upgradeFromVersion);
 
+                if ("2.5.0-cassandra".equals(upgradeFromVersion)) {
+                    log.info("Migrating ThingsBoard entities data from cassandra to SQL database ...");
+                    entitiesMigrateService.migrate();
+                    log.info("Updating system data...");
+                    systemDataLoaderService.updateSystemWidgets();
+                } else {
                     switch (upgradeFromVersion) {
                         case "1.2.3": //NOSONAR, Need to execute gradual upgrade starting from upgradeFromVersion
                             log.info("Upgrading ThingsBoard from version 1.2.3 to 1.3.0 ...");
@@ -142,26 +152,13 @@ public class ThingsboardInstallService {
 
                             log.info("Updating system data...");
 
-                        systemDataLoaderService.deleteSystemWidgetBundle("charts");
+                            systemDataLoaderService.updateSystemWidgets();
-                        systemDataLoaderService.deleteSystemWidgetBundle("cards");
-                        systemDataLoaderService.deleteSystemWidgetBundle("maps");
-                        systemDataLoaderService.deleteSystemWidgetBundle("analogue_gauges");
-                        systemDataLoaderService.deleteSystemWidgetBundle("digital_gauges");
-                        systemDataLoaderService.deleteSystemWidgetBundle("gpio_widgets");
-                        systemDataLoaderService.deleteSystemWidgetBundle("alarm_widgets");
-                        systemDataLoaderService.deleteSystemWidgetBundle("control_widgets");
-                        systemDataLoaderService.deleteSystemWidgetBundle("maps_v2");
-                        systemDataLoaderService.deleteSystemWidgetBundle("gateway_widgets");
-                        systemDataLoaderService.deleteSystemWidgetBundle("input_widgets");
-                        systemDataLoaderService.deleteSystemWidgetBundle("date");
-                        systemDataLoaderService.deleteSystemWidgetBundle("entity_admin_widgets");
-
-                        systemDataLoaderService.loadSystemWidgets();
                             break;
                         default:
                             throw new RuntimeException("Unable to upgrade ThingsBoard, unsupported fromVersion: " + upgradeFromVersion);
 
                     }
+                }
                 log.info("Upgrade finished successfully!");
 
             } else {

application/src/main/java/org/thingsboard/server/service/install/DefaultSystemDataLoaderService.java

@@ -168,6 +168,24 @@ public class DefaultSystemDataLoaderService implements SystemDataLoaderService {
         installScripts.loadSystemWidgets();
     }
 
+    @Override
+    public void updateSystemWidgets() throws Exception {
+        this.deleteSystemWidgetBundle("charts");
+        this.deleteSystemWidgetBundle("cards");
+        this.deleteSystemWidgetBundle("maps");
+        this.deleteSystemWidgetBundle("analogue_gauges");
+        this.deleteSystemWidgetBundle("digital_gauges");
+        this.deleteSystemWidgetBundle("gpio_widgets");
+        this.deleteSystemWidgetBundle("alarm_widgets");
+        this.deleteSystemWidgetBundle("control_widgets");
+        this.deleteSystemWidgetBundle("maps_v2");
+        this.deleteSystemWidgetBundle("gateway_widgets");
+        this.deleteSystemWidgetBundle("input_widgets");
+        this.deleteSystemWidgetBundle("date");
+        this.deleteSystemWidgetBundle("entity_admin_widgets");
+        installScripts.loadSystemWidgets();
+    }
+
     private User createUser(Authority authority,
                             TenantId tenantId,
                             CustomerId customerId,

application/src/main/java/org/thingsboard/server/service/install/SystemDataLoaderService.java

@@ -23,6 +23,8 @@ public interface SystemDataLoaderService {
 
     void loadSystemWidgets() throws Exception;
 
+    void updateSystemWidgets() throws Exception;
+
     void loadDemoData() throws Exception;
 
     void deleteSystemWidgetBundle(String bundleAlias) throws Exception;

application/src/main/java/org/thingsboard/server/service/install/migrate/CassandraEntitiesToSqlMigrateService.java

@@ -0,0 +1,253 @@
+package org.thingsboard.server.service.install.migrate;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Profile;
+import org.springframework.stereotype.Service;
+import org.thingsboard.server.common.data.EntityType;
+import org.thingsboard.server.dao.cassandra.CassandraCluster;
+import org.thingsboard.server.dao.util.SqlDao;
+import org.thingsboard.server.service.install.EntityDatabaseSchemaService;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.util.Arrays;
+import java.util.List;
+
+import static org.thingsboard.server.service.install.migrate.CassandraToSqlColumn.bigintColumn;
+import static org.thingsboard.server.service.install.migrate.CassandraToSqlColumn.booleanColumn;
+import static org.thingsboard.server.service.install.migrate.CassandraToSqlColumn.doubleColumn;
+import static org.thingsboard.server.service.install.migrate.CassandraToSqlColumn.enumToIntColumn;
+import static org.thingsboard.server.service.install.migrate.CassandraToSqlColumn.idColumn;
+import static org.thingsboard.server.service.install.migrate.CassandraToSqlColumn.stringColumn;
+
+@Service
+@Profile("install")
+@SqlDao
+@Slf4j
+public class CassandraEntitiesToSqlMigrateService implements EntitiesMigrateService {
+
+    @Autowired
+    private EntityDatabaseSchemaService entityDatabaseSchemaService;
+
+    @Autowired
+    protected CassandraCluster cluster;
+
+    @Value("${spring.datasource.url}")
+    protected String dbUrl;
+
+    @Value("${spring.datasource.username}")
+    protected String dbUserName;
+
+    @Value("${spring.datasource.password}")
+    protected String dbPassword;
+
+
+    @Override
+    public void migrate() throws Exception {
+        log.info("Performing migration of entities data from cassandra to SQL database ...");
+        entityDatabaseSchemaService.createDatabaseSchema();
+        try (Connection conn = DriverManager.getConnection(dbUrl, dbUserName, dbPassword)) {
+            conn.setAutoCommit(true);
+            for (CassandraToSqlTable table: tables) {
+                table.migrateToSql(cluster.getSession(), conn);
+            }
+        } catch (Exception e) {
+            log.error("Unexpected error during ThingsBoard entities data migration!", e);
+            throw e;
+        }
+    }
+
+    private static List<CassandraToSqlTable> tables = Arrays.asList(
+        new CassandraToSqlTable("admin_settings",
+                idColumn("id"),
+                stringColumn("key"),
+                stringColumn("json_value")),
+        new CassandraToSqlTable("alarm",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                stringColumn("type"),
+                idColumn("originator_id"),
+                enumToIntColumn("originator_type", EntityType.class),
+                stringColumn("severity"),
+                stringColumn("status"),
+                bigintColumn("start_ts"),
+                bigintColumn("end_ts"),
+                bigintColumn("ack_ts"),
+                bigintColumn("clear_ts"),
+                stringColumn("details", "additional_info"),
+                booleanColumn("propagate"),
+                stringColumn("propagate_relation_types")),
+        new CassandraToSqlTable("asset",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                idColumn("customer_id"),
+                stringColumn("name"),
+                stringColumn("type"),
+                stringColumn("label"),
+                stringColumn("search_text"),
+                stringColumn("additional_info")),
+        new CassandraToSqlTable("audit_log_by_tenant_id", "audit_log",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                idColumn("customer_id"),
+                idColumn("entity_id"),
+                stringColumn("entity_type"),
+                stringColumn("entity_name"),
+                idColumn("user_id"),
+                stringColumn("user_name"),
+                stringColumn("action_type"),
+                stringColumn("action_data"),
+                stringColumn("action_status"),
+                stringColumn("action_failure_details")),
+        new CassandraToSqlTable("attributes_kv_cf", "attribute_kv",
+                idColumn("entity_id"),
+                stringColumn("entity_type"),
+                stringColumn("attribute_type"),
+                stringColumn("attribute_key"),
+                booleanColumn("bool_v"),
+                stringColumn("str_v"),
+                bigintColumn("long_v"),
+                doubleColumn("dbl_v"),
+                stringColumn("json_v"),
+                bigintColumn("last_update_ts")),
+        new CassandraToSqlTable("component_descriptor",
+                idColumn("id"),
+                stringColumn("type"),
+                stringColumn("scope"),
+                stringColumn("name"),
+                stringColumn("search_text"),
+                stringColumn("clazz"),
+                stringColumn("configuration_descriptor"),
+                stringColumn("actions")),
+        new CassandraToSqlTable("customer",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                stringColumn("title"),
+                stringColumn("search_text"),
+                stringColumn("country"),
+                stringColumn("state"),
+                stringColumn("city"),
+                stringColumn("address"),
+                stringColumn("address2"),
+                stringColumn("zip"),
+                stringColumn("phone"),
+                stringColumn("email"),
+                stringColumn("additional_info")),
+        new CassandraToSqlTable("dashboard",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                stringColumn("title"),
+                stringColumn("search_text"),
+                stringColumn("assigned_customers"),
+                stringColumn("configuration")),
+        new CassandraToSqlTable("device",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                idColumn("customer_id"),
+                stringColumn("name"),
+                stringColumn("type"),
+                stringColumn("label"),
+                stringColumn("search_text"),
+                stringColumn("additional_info")),
+        new CassandraToSqlTable("device_credentials",
+                idColumn("id"),
+                idColumn("device_id"),
+                stringColumn("credentials_type"),
+                stringColumn("credentials_id"),
+                stringColumn("credentials_value")),
+        new CassandraToSqlTable("event",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                idColumn("entity_id"),
+                stringColumn("entity_type"),
+                stringColumn("event_type"),
+                stringColumn("event_uid"),
+                stringColumn("body")),
+        new CassandraToSqlTable("relation",
+                idColumn("from_id"),
+                stringColumn("from_type"),
+                idColumn("to_id"),
+                stringColumn("to_type"),
+                stringColumn("relation_type_group"),
+                stringColumn("relation_type"),
+                stringColumn("additional_info")),
+        new CassandraToSqlTable("user", "tb_user",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                idColumn("customer_id"),
+                stringColumn("email"),
+                stringColumn("search_text"),
+                stringColumn("authority"),
+                stringColumn("first_name"),
+                stringColumn("last_name"),
+                stringColumn("additional_info")),
+        new CassandraToSqlTable("tenant",
+                idColumn("id"),
+                stringColumn("title"),
+                stringColumn("search_text"),
+                stringColumn("region"),
+                stringColumn("country"),
+                stringColumn("state"),
+                stringColumn("city"),
+                stringColumn("address"),
+                stringColumn("address2"),
+                stringColumn("zip"),
+                stringColumn("phone"),
+                stringColumn("email"),
+                stringColumn("additional_info")),
+        new CassandraToSqlTable("user_credentials",
+                idColumn("id"),
+                idColumn("user_id"),
+                booleanColumn("enabled"),
+                stringColumn("password"),
+                stringColumn("activate_token"),
+                stringColumn("reset_token")),
+        new CassandraToSqlTable("widget_type",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                stringColumn("bundle_alias"),
+                stringColumn("alias"),
+                stringColumn("name"),
+                stringColumn("descriptor")),
+        new CassandraToSqlTable("widgets_bundle",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                stringColumn("alias"),
+                stringColumn("title"),
+                stringColumn("search_text")),
+        new CassandraToSqlTable("rule_chain",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                stringColumn("name"),
+                stringColumn("search_text"),
+                idColumn("first_rule_node_id"),
+                booleanColumn("root"),
+                booleanColumn("debug_mode"),
+                stringColumn("configuration"),
+                stringColumn("additional_info")),
+        new CassandraToSqlTable("rule_node",
+                idColumn("id"),
+                idColumn("rule_chain_id"),
+                stringColumn("type"),
+                stringColumn("name"),
+                booleanColumn("debug_mode"),
+                stringColumn("search_text"),
+                stringColumn("configuration"),
+                stringColumn("additional_info")),
+        new CassandraToSqlTable("entity_view",
+                idColumn("id"),
+                idColumn("tenant_id"),
+                idColumn("customer_id"),
+                idColumn("entity_id"),
+                stringColumn("entity_type"),
+                stringColumn("name"),
+                stringColumn("type"),
+                stringColumn("keys"),
+                bigintColumn("start_ts"),
+                bigintColumn("end_ts"),
+                stringColumn("search_text"),
+                stringColumn("additional_info"))
+    );
+}

application/src/main/java/org/thingsboard/server/service/install/migrate/CassandraToSqlColumn.java

@@ -0,0 +1,159 @@
+package org.thingsboard.server.service.install.migrate;
+
+import com.datastax.driver.core.Row;
+import lombok.Data;
+import org.thingsboard.server.common.data.UUIDConverter;
+
+import java.sql.PreparedStatement;
+import java.sql.SQLException;
+import java.sql.Types;
+
+@Data
+public class CassandraToSqlColumn {
+
+    private String cassandraColumnName;
+    private String sqlColumnName;
+    private CassandraToSqlColumnType type;
+    private int sqlType;
+    private Class<? extends Enum> enumClass;
+
+    public static CassandraToSqlColumn idColumn(String name) {
+        return new CassandraToSqlColumn(name, CassandraToSqlColumnType.ID);
+    }
+
+    public static CassandraToSqlColumn stringColumn(String name) {
+        return new CassandraToSqlColumn(name, CassandraToSqlColumnType.STRING);
+    }
+
+    public static CassandraToSqlColumn stringColumn(String cassandraColumnName, String sqlColumnName) {
+        return new CassandraToSqlColumn(cassandraColumnName, sqlColumnName);
+    }
+
+    public static CassandraToSqlColumn bigintColumn(String name) {
+        return new CassandraToSqlColumn(name, CassandraToSqlColumnType.BIGINT);
+    }
+
+    public static CassandraToSqlColumn doubleColumn(String name) {
+        return new CassandraToSqlColumn(name, CassandraToSqlColumnType.DOUBLE);
+    }
+
+    public static CassandraToSqlColumn booleanColumn(String name) {
+        return new CassandraToSqlColumn(name, CassandraToSqlColumnType.BOOLEAN);
+    }
+
+    public static CassandraToSqlColumn enumToIntColumn(String name, Class<? extends Enum> enumClass) {
+        return new CassandraToSqlColumn(name, CassandraToSqlColumnType.ENUM_TO_INT, enumClass);
+    }
+
+    public CassandraToSqlColumn(String columnName) {
+        this(columnName, columnName, CassandraToSqlColumnType.STRING, null);
+    }
+
+    public CassandraToSqlColumn(String columnName, CassandraToSqlColumnType type) {
+        this(columnName, columnName, type, null);
+    }
+
+    public CassandraToSqlColumn(String columnName, CassandraToSqlColumnType type, Class<? extends Enum> enumClass) {
+        this(columnName, columnName, type, enumClass);
+    }
+
+    public CassandraToSqlColumn(String cassandraColumnName, String sqlColumnName) {
+        this(cassandraColumnName, sqlColumnName, CassandraToSqlColumnType.STRING, null);
+    }
+
+    public CassandraToSqlColumn(String cassandraColumnName, String sqlColumnName, CassandraToSqlColumnType type,
+                                Class<? extends Enum> enumClass) {
+        this.cassandraColumnName = cassandraColumnName;
+        this.sqlColumnName = sqlColumnName;
+        this.type = type;
+        this.enumClass = enumClass;
+        switch (this.type) {
+            case ID:
+            case STRING:
+                this.sqlType = Types.VARCHAR;
+                break;
+            case DOUBLE:
+                this.sqlType = Types.DOUBLE;
+                break;
+            case INTEGER:
+            case ENUM_TO_INT:
+                this.sqlType = Types.INTEGER;
+                break;
+            case FLOAT:
+                this.sqlType = Types.FLOAT;
+                break;
+            case BIGINT:
+                this.sqlType = Types.BIGINT;
+                break;
+            case BOOLEAN:
+                this.sqlType = Types.BOOLEAN;
+                break;
+        }
+    }
+
+    public void prepareColumnValue(Row row, PreparedStatement sqlInsertStatement, int index) throws SQLException {
+        String value = this.getColumnValue(row, index);
+        this.setColumnValue(sqlInsertStatement, index, value);
+    }
+
+    private String getColumnValue(Row row, int index) {
+        if (row.isNull(index)) {
+            return null;
+        } else {
+            switch (this.type) {
+                case ID:
+                    return UUIDConverter.fromTimeUUID(row.getUUID(index));
+                case DOUBLE:
+                    return Double.toString(row.getDouble(index));
+                case INTEGER:
+                    return Integer.toString(row.getInt(index));
+                case FLOAT:
+                    return Float.toString(row.getFloat(index));
+                case BIGINT:
+                    return Long.toString(row.getLong(index));
+                case BOOLEAN:
+                    return Boolean.toString(row.getBool(index));
+                case STRING:
+                case ENUM_TO_INT:
+                default:
+                   return row.getString(index);
+            }
+        }
+    }
+
+    private void setColumnValue(PreparedStatement sqlInsertStatement, int index, String value) throws SQLException {
+        if (value == null) {
+            sqlInsertStatement.setNull(index, this.sqlType);
+        } else {
+            switch (this.type) {
+                case DOUBLE:
+                    sqlInsertStatement.setDouble(index, Double.parseDouble(value));
+                    break;
+                case INTEGER:
+                    sqlInsertStatement.setInt(index, Integer.parseInt(value));
+                    break;
+                case FLOAT:
+                    sqlInsertStatement.setFloat(index, Float.parseFloat(value));
+                    break;
+                case BIGINT:
+                    sqlInsertStatement.setLong(index, Long.parseLong(value));
+                    break;
+                case BOOLEAN:
+                    sqlInsertStatement.setBoolean(index, Boolean.parseBoolean(value));
+                    break;
+                case ENUM_TO_INT:
+                    Enum enumVal = Enum.valueOf(this.enumClass, value);
+                    int intValue = enumVal.ordinal();
+                    sqlInsertStatement.setInt(index, intValue);
+                    break;
+                case STRING:
+                case ID:
+                default:
+                    sqlInsertStatement.setString(index, value);
+                    break;
+            }
+        }
+    }
+
+}
+

application/src/main/java/org/thingsboard/server/service/install/migrate/CassandraToSqlColumnType.java

@@ -0,0 +1,12 @@
+package org.thingsboard.server.service.install.migrate;
+
+public enum CassandraToSqlColumnType {
+    ID,
+    DOUBLE,
+    INTEGER,
+    FLOAT,
+    BIGINT,
+    BOOLEAN,
+    STRING,
+    ENUM_TO_INT
+}

application/src/main/java/org/thingsboard/server/service/install/migrate/CassandraToSqlTable.java

@@ -0,0 +1,99 @@
+package org.thingsboard.server.service.install.migrate;
+
+import com.datastax.driver.core.ResultSet;
+import com.datastax.driver.core.Row;
+import com.datastax.driver.core.Session;
+import com.datastax.driver.core.SimpleStatement;
+import com.datastax.driver.core.Statement;
+import lombok.Data;
+import lombok.extern.slf4j.Slf4j;
+
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.SQLException;
+import java.util.Arrays;
+import java.util.Iterator;
+import java.util.List;
+
+@Data
+@Slf4j
+public class CassandraToSqlTable {
+
+    private String cassandraCf;
+    private String sqlTableName;
+
+    private List<CassandraToSqlColumn> columns;
+
+    public CassandraToSqlTable(String tableName, CassandraToSqlColumn... columns) {
+        this(tableName, tableName, columns);
+    }
+
+    public CassandraToSqlTable(String cassandraCf, String sqlTableName, CassandraToSqlColumn... columns) {
+        this.cassandraCf = cassandraCf;
+        this.sqlTableName = sqlTableName;
+        this.columns = Arrays.asList(columns);
+    }
+
+    public void migrateToSql(Session session, Connection conn) throws SQLException {
+        log.info("Migrating data from cassandra '{}' Column Family to '{}' SQL table...", this.cassandraCf, this.sqlTableName);
+        PreparedStatement sqlInsertStatement = createSqlInsertStatement(conn);
+        Statement cassandraSelectStatement = createCassandraSelectStatement();
+        cassandraSelectStatement.setFetchSize(100);
+        ResultSet rs = session.execute(cassandraSelectStatement);
+        Iterator<Row> iter = rs.iterator();
+        int rowCounter = 0;
+        while (iter.hasNext()) {
+            Row row = iter.next();
+            if (row != null) {
+                this.migrateRowToSql(row, sqlInsertStatement);
+                rowCounter++;
+                if (rowCounter % 100 == 0) {
+                    sqlInsertStatement.executeBatch();
+                    log.info("{} records migrated so far...", rowCounter);
+                }
+            }
+        }
+        if (rowCounter % 100 > 0) {
+            sqlInsertStatement.executeBatch();
+        }
+        sqlInsertStatement.close();
+        log.info("{} total records migrated.", rowCounter);
+        log.info("Finished migration data from cassandra '{}' Column Family to '{}' SQL table.", this.cassandraCf, this.sqlTableName);
+    }
+
+    private void migrateRowToSql(Row row, PreparedStatement sqlInsertStatement) throws SQLException {
+        for (int i=0; i<this.columns.size();i++) {
+            CassandraToSqlColumn column = this.columns.get(i);
+            column.prepareColumnValue(row, sqlInsertStatement, i);
+        }
+        sqlInsertStatement.addBatch();
+    }
+
+    private Statement createCassandraSelectStatement() {
+        StringBuilder selectStatementBuilder = new StringBuilder();
+        selectStatementBuilder.append("SELECT ");
+        for (CassandraToSqlColumn column : columns) {
+            selectStatementBuilder.append(column.getCassandraColumnName()).append(",");
+        }
+        selectStatementBuilder.deleteCharAt(selectStatementBuilder.length() - 1);
+        selectStatementBuilder.append(" FROM ").append(cassandraCf);
+        return new SimpleStatement(selectStatementBuilder.toString());
+    }
+
+    private PreparedStatement createSqlInsertStatement(Connection conn) throws SQLException {
+        StringBuilder insertStatementBuilder = new StringBuilder();
+        insertStatementBuilder.append("INSERT INTO ").append(this.sqlTableName).append(" (");
+        for (CassandraToSqlColumn column : columns) {
+            insertStatementBuilder.append(column.getSqlColumnName()).append(",");
+        }
+        insertStatementBuilder.deleteCharAt(insertStatementBuilder.length() - 1);
+        insertStatementBuilder.append(") VALUES (");
+        for (CassandraToSqlColumn ignored : columns) {
+            insertStatementBuilder.append("?").append(",");
+        }
+        insertStatementBuilder.deleteCharAt(insertStatementBuilder.length() - 1);
+        insertStatementBuilder.append(")");
+        return conn.prepareStatement(insertStatementBuilder.toString());
+    }
+
+}

application/src/main/java/org/thingsboard/server/service/install/migrate/EntitiesMigrateService.java

@@ -0,0 +1,7 @@
+package org.thingsboard.server.service.install.migrate;
+
+public interface EntitiesMigrateService {
+
+    void migrate() throws Exception;
+
+}