Enable mutation parameter

README.md

@@ -217,6 +217,13 @@ Assuming you started a test environment using docker-compose, please refer to ex
 
 * Mutation
     ```sql
+    -- use query parameter
+    select * from jdbc('ch-server?mutation', 'drop table if exists system.test_table');
+    select * from jdbc('ch-server?mutation', 'create table system.test_table(a String, b UInt8) engine=Memory()');
+    select * from jdbc('ch-server?mutation', 'insert into system.test_table values(''a'', 1)');
+	select * from jdbc('ch-server?mutation', 'truncate table system.test_table');
+
+    -- use JDBC table engine
     drop table if exists system.test_table;
     create table system.test_table (
         a String,
@@ -302,8 +309,9 @@ Assuming you started a test environment using docker-compose, please refer to ex
     Couple of timeout settings you should be aware of:
     1. datasource timeout, for example: `max_execution_time` in MariaDB
     2. JDBC driver timeout, for example: `connectTimeout` and `socketTimeout` in [MariaDB Connector/J](https://mariadb.com/kb/en/about-mariadb-connector-j/)
-    3. Vertx timeout - see `config/server.json` and `config/vertx.json`
-    4. Client(ClickHouse JDBC driver) timeout - see timeout settings in ClickHouse JDBC driver
+    3. JDBC bridge timeout, for examples: `queryTimeout` in `config/server.json`, and `maxWorkerExecuteTime` in `config/vertx.json`
+    4. ClickHouse timeout like `max_execution_time` and `keep_alive_timeout` etc.
+    5. Client timeout, for example: `socketTimeout` in ClickHouse JDBC driver
 
 
 ## Migration

src/main/java/ru/yandex/clickhouse/jdbcbridge/JdbcBridgeVerticle.java

@@ -528,7 +528,9 @@ private void handleWrite(RoutingContext ctx) {
         ds.executeMutation(parser.getRawSchema(), table, parser.getTable(), params, ByteBuffer.wrap(ctx.getBody()),
                 writer);
 
-        resp.end(ByteBuffer.asBuffer(WRITE_RESPONSE));
+        if (writer.isOpen()) {
+            resp.end(ByteBuffer.asBuffer(WRITE_RESPONSE));
+        }
     }
 
     private Repository<NamedDataSource> getDataSourceRepository() {

src/main/java/ru/yandex/clickhouse/jdbcbridge/core/NamedDataSource.java

@@ -185,6 +185,36 @@ private void writeDebugResult(String schema, String originalQuery, String loaded
         Objects.requireNonNull(writer).write(buffer);
     }
 
+    protected final void writeMutationResult(long effectedRows, ColumnDefinition[] requestColumns,
+            ColumnDefinition[] customColumns, ResponseWriter writer) {
+        ByteBuffer buffer = ByteBuffer.newInstance(100);
+        Map<String, String> values = new HashMap<>();
+        for (ColumnDefinition c : customColumns) {
+            values.put(c.getName(), converter.as(String.class, c.getValue()));
+        }
+
+        String typeName = TableDefinition.MUTATION_COLUMNS.getColumn(0).getName();
+        String rowsName = TableDefinition.MUTATION_COLUMNS.getColumn(1).getName();
+
+        values.put(typeName, this.getType());
+
+        for (ColumnDefinition c : requestColumns) {
+            String name = c.getName();
+            if (rowsName.equals(name)) {
+                buffer.writeUInt64(effectedRows);
+            } else {
+                String str = values.get(name);
+                if (str == null) {
+                    buffer.writeNull();
+                } else {
+                    buffer.writeNonNull().writeString(str);
+                }
+            }
+        }
+
+        Objects.requireNonNull(writer).write(buffer);
+    }
+
     protected void writeMutationResult(String schema, String originalQuery, String loadedQuery, QueryParameters params,
             ColumnDefinition[] requestColumns, ColumnDefinition[] customColumns, DefaultValues defaultValues,
             ResponseWriter writer) {

src/main/java/ru/yandex/clickhouse/jdbcbridge/core/TableDefinition.java

@@ -59,7 +59,8 @@ public class TableDefinition {
             // datasource type: jdbc, config, script etc.
             new ColumnDefinition("type", DataType.Str, true, DEFAULT_LENGTH, DEFAULT_PRECISION, DEFAULT_SCALE),
             // operation: read or write
-            new ColumnDefinition("operation", DataType.Str, true, DEFAULT_LENGTH, DEFAULT_PRECISION, DEFAULT_SCALE),
+            // new ColumnDefinition("operation", DataType.Str, true, DEFAULT_LENGTH,
+            // DEFAULT_PRECISION, DEFAULT_SCALE),
             new ColumnDefinition("rows", DataType.UInt64, false, DEFAULT_LENGTH, DEFAULT_PRECISION, DEFAULT_SCALE));
 
     private static final String COLUMN_HEADER = "columns format version: ";

src/main/java/ru/yandex/clickhouse/jdbcbridge/impl/JdbcDataSource.java

@@ -517,6 +517,20 @@ protected final void setTimeout(Statement stmt, int expectedTimeout) {
         }
     }
 
+    protected long getFirstMutationResult(Statement stmt) throws SQLException {
+        long count = 0L;
+
+        try {
+            count = stmt.getLargeUpdateCount();
+        } catch (SQLException e) {
+            throw e;
+        } catch (Exception e) {
+            count = stmt.getUpdateCount();
+        }
+
+        return count == -1 ? 0 : count;
+    }
+
     protected ResultSet getFirstQueryResult(Statement stmt, boolean hasResultSet) throws SQLException {
         ResultSet rs = null;
 
@@ -654,27 +668,14 @@ protected void writeMutationResult(String schema, String originalQuery, String l
         try (Connection conn = getConnection(); Statement stmt = createStatement(conn, params)) {
             setTimeout(stmt, this.getQueryTimeout(params.getTimeout()));
 
-            final ResultSet rs = getFirstQueryResult(stmt, stmt.execute(loadedQuery));
-
-            DataTableReader reader = new ResultSetReader(getId(), rs, params);
-            reader.process(getId(), requestColumns, customColumns, getColumnsFromResultSet(rs, params), defaultValues,
-                    getTimeZone(), params, writer);
-
-            /*
-             * if (stmt.execute(loadedQuery)) { // TODO multiple resultsets
-             * 
-             * } else if (columns.size() == 1 && columns.getColumn(0).getType() ==
-             * ClickHouseDataType.Int32) {
-             * writer.write(ClickHouseBuffer.newInstance(4).writeInt32(stmt.getUpdateCount()
-             * )); } else { throw new IllegalStateException(
-             * "Not able to handle query result due to incompatible columns: " + columns); }
-             */
+            stmt.execute(loadedQuery);
+            this.writeMutationResult(getFirstMutationResult(stmt), requestColumns, customColumns, writer);
         } catch (SQLException e) {
             throw new DataAccessException(getId(), buildErrorMessage(e), e);
         } catch (DataAccessException e) {
             Throwable cause = e.getCause();
             throw new IllegalStateException(
-                    "Failed to query against [" + this.getId() + "] due to: " + buildErrorMessage(cause), cause);
+                    "Failed to mutate against [" + this.getId() + "] due to: " + buildErrorMessage(cause), cause);
         }
     }