[draft]Use Apache Doris as the data connection source

platform/backend_connectors/basic_sql_backend_connector.go

@@ -7,6 +7,7 @@ import (
 	"context"
 	"database/sql"
 	"github.com/QuesmaOrg/quesma/platform/config"
+	"github.com/QuesmaOrg/quesma/platform/logger"
 	quesma_api "github.com/QuesmaOrg/quesma/platform/v2/core"
 )
 
@@ -64,6 +65,7 @@ func (p *BasicSqlBackendConnector) Ping() error {
 }
 
 func (p *BasicSqlBackendConnector) Query(ctx context.Context, query string, args ...interface{}) (quesma_api.Rows, error) {
+	logger.Info().Msgf("query sql: %s", query)
 	rows, err := p.connection.QueryContext(ctx, query, args...)
 	if err != nil {
 		return nil, err
@@ -72,10 +74,12 @@ func (p *BasicSqlBackendConnector) Query(ctx context.Context, query string, args
 }
 
 func (p *BasicSqlBackendConnector) QueryRow(ctx context.Context, query string, args ...interface{}) quesma_api.Row {
+	logger.Info().Msgf("queryRow sql: %s", query)
 	return p.connection.QueryRowContext(ctx, query, args...)
 }
 
 func (p *BasicSqlBackendConnector) Exec(ctx context.Context, query string, args ...interface{}) error {
+	logger.Info().Msgf("Exec sql: %s", query)
 	if len(args) == 0 {
 		_, err := p.connection.ExecContext(ctx, query)
 		return err

platform/clickhouse/connection.go

@@ -6,9 +6,7 @@ import (
 	"crypto/tls"
 	"database/sql"
 	"fmt"
-	"github.com/ClickHouse/clickhouse-go/v2"
 	"github.com/QuesmaOrg/quesma/platform/backend_connectors"
-	"github.com/QuesmaOrg/quesma/platform/buildinfo"
 	"github.com/QuesmaOrg/quesma/platform/config"
 	"github.com/QuesmaOrg/quesma/platform/logger"
 	quesma_api "github.com/QuesmaOrg/quesma/platform/v2/core"
@@ -19,40 +17,68 @@ import (
 
 func initDBConnection(c *config.QuesmaConfiguration, tlsConfig *tls.Config) *sql.DB {
 
-	options := clickhouse.Options{Addr: []string{c.ClickHouse.Url.Host}}
-	if c.ClickHouse.User != "" || c.ClickHouse.Password != "" || c.ClickHouse.Database != "" {
+	dsn := fmt.Sprintf("%s:%s@tcp(%s)/%s?charset=utf8mb4&parseTime=true",
+		c.ClickHouse.User,
+		c.ClickHouse.Password,
+		c.ClickHouse.Url.Host,
+		c.ClickHouse.Database)
 
-		options.Auth = clickhouse.Auth{
-			Username: c.ClickHouse.User,
-			Password: c.ClickHouse.Password,
-			Database: c.ClickHouse.Database,
-		}
-	}
-	if !c.ClickHouse.DisableTLS {
-		options.TLS = tlsConfig
-	}
-
-	info := struct {
-		Name    string
-		Version string
-	}{
-		Name:    "quesma",
-		Version: buildinfo.Version,
+	db, err := sql.Open("mysql", dsn)
+	if err != nil {
+		logger.Error().Err(err).Msg("failed to initialize Doris connection pool")
+		return nil
 	}
 
-	// Setting limit here is not working. It causes runtime error.
-	// Set it after opening the connection.
-	//
-	//	options.MaxIdleConns = 50
-	//	options.MaxOpenConns = 50
-	//	options.ConnMaxLifetime = 0
+	db.SetMaxOpenConns(30)
+	db.SetMaxIdleConns(10)
+	db.SetConnMaxLifetime(time.Hour)
 
-	options.ClientInfo.Products = append(options.ClientInfo.Products, info)
+	if err := db.Ping(); err != nil {
+		logger.Error().Err(err).Msg("failed to ping Doris server")
+		return nil
+	}
 
-	return clickhouse.OpenDB(&options)
+	logger.Info().Msg("Doris connection pool initialized successfully")
+	return db
 
 }
 
+//func initDBConnection(c *config.QuesmaConfiguration, tlsConfig *tls.Config) *sql.DB {
+//
+//	options := clickhouse.Options{Addr: []string{c.ClickHouse.Url.Host}}
+//	if c.ClickHouse.User != "" || c.ClickHouse.Password != "" || c.ClickHouse.Database != "" {
+//
+//		options.Auth = clickhouse.Auth{
+//			Username: c.ClickHouse.User,
+//			Password: c.ClickHouse.Password,
+//			Database: c.ClickHouse.Database,
+//		}
+//	}
+//	if !c.ClickHouse.DisableTLS {
+//		options.TLS = tlsConfig
+//	}
+//
+//	info := struct {
+//		Name    string
+//		Version string
+//	}{
+//		Name:    "quesma",
+//		Version: buildinfo.Version,
+//	}
+//
+//	// Setting limit here is not working. It causes runtime error.
+//	// Set it after opening the connection.
+//	//
+//	//	options.MaxIdleConns = 50
+//	//	options.MaxOpenConns = 50
+//	//	options.ConnMaxLifetime = 0
+//
+//	options.ClientInfo.Products = append(options.ClientInfo.Products, info)
+//
+//	return clickhouse.OpenDB(&options)
+//
+//}
+
 func InitDBConnectionPool(c *config.QuesmaConfiguration) quesma_api.BackendConnector {
 	if c.ClickHouse.Url == nil {
 		return nil

platform/clickhouse/quesma_communicator.go

@@ -223,7 +223,15 @@ func read(ctx context.Context, rows quesma_api.Rows, selectFields []string, rowT
 		}
 		resultRow := model.QueryResultRow{Cols: make([]model.QueryResultCol, len(selectFields))}
 		for i, field := range selectFields {
-			resultRow.Cols[i] = model.QueryResultCol{ColName: field, Value: rowToScan[i]}
+			var val interface{}
+			switch v := rowToScan[i].(type) {
+			// just for doris query
+			case []uint8:
+				val = string(v)
+			default:
+				val = v
+			}
+			resultRow.Cols[i] = model.QueryResultCol{ColName: field, Value: val}
 		}
 		resultRows = append(resultRows, resultRow)
 	}

platform/clickhouse/schema.go

@@ -73,6 +73,7 @@ const (
 	DateTime64 DateTimeType = iota
 	DateTime
 	Invalid
+	datetime
 )
 
 func (c *Column) String() string {
@@ -220,35 +221,75 @@ func NewBaseType(clickHouseTypeName string) BaseType {
 // this is catch all type for all types we do not exlicitly support
 type UnknownType struct{}
 
-func ResolveType(clickHouseTypeName string) reflect.Type {
-	switch clickHouseTypeName {
-	case "String", "LowCardinality(String)", "UUID", "FixedString":
+func ResolveType(dorisTypeName string) reflect.Type {
+	dorisTypeName = strings.ToLower(dorisTypeName)
+	switch dorisTypeName {
+	case "char", "varchar", "string", "text":
 		return reflect.TypeOf("")
-	case "DateTime64", "DateTime", "Date", "DateTime64(3)":
+	case "date", "datetime", "datev2", "datetimev2":
 		return reflect.TypeOf(time.Time{})
-	case "UInt8", "UInt16", "UInt32", "UInt64":
-		return reflect.TypeOf(uint64(0))
-	case "Int8", "Int16", "Int32":
+	case "tinyint", "smallint", "int":
 		return reflect.TypeOf(int32(0))
-	case "Int64":
+	case "bigint":
 		return reflect.TypeOf(int64(0))
-	case "Float32", "Float64":
-		return reflect.TypeOf(float64(0))
-	case "Point":
-		return reflect.TypeOf(Point{})
-	case "Bool":
+	case "largeint":
+		return reflect.TypeOf("") // LargeInt is typically handled as string due to size
+	case "boolean":
 		return reflect.TypeOf(true)
-	case "JSON":
+	case "float":
+		return reflect.TypeOf(float32(0))
+	case "double":
+		return reflect.TypeOf(float64(0))
+	case "decimal", "decimalv2", "decimal32", "decimal64", "decimal128":
+		return reflect.TypeOf("") // Decimals often handled as strings for precision
+	case "json":
+		return reflect.TypeOf(map[string]interface{}{})
+	case "hll":
+		return reflect.TypeOf([]byte{}) // HLL is a binary type
+	case "bitmap":
+		return reflect.TypeOf([]byte{}) // Bitmap is also binary
+	case "array":
+		return reflect.TypeOf([]interface{}{})
+	case "map":
 		return reflect.TypeOf(map[string]interface{}{})
-	case "Map(String, Nullable(String))", "Map(String, String)", "Map(LowCardinality(String), String)", "Map(LowCardinality(String), Nullable(String))":
-		return reflect.TypeOf(map[string]string{})
-	case "Unknown":
-		return reflect.TypeOf(UnknownType{})
+	case "struct":
+		return reflect.TypeOf(map[string]interface{}{})
+	case "null":
+		return reflect.TypeOf(nil)
 	}
 
 	return nil
 }
 
+//func ResolveType(clickHouseTypeName string) reflect.Type {
+//	switch clickHouseTypeName {
+//	case "String", "LowCardinality(String)", "UUID", "FixedString":
+//		return reflect.TypeOf("")
+//	case "DateTime64", "DateTime", "Date", "DateTime64(3)":
+//		return reflect.TypeOf(time.Time{})
+//	case "UInt8", "UInt16", "UInt32", "UInt64":
+//		return reflect.TypeOf(uint64(0))
+//	case "Int8", "Int16", "Int32":
+//		return reflect.TypeOf(int32(0))
+//	case "Int64":
+//		return reflect.TypeOf(int64(0))
+//	case "Float32", "Float64":
+//		return reflect.TypeOf(float64(0))
+//	case "Point":
+//		return reflect.TypeOf(Point{})
+//	case "Bool":
+//		return reflect.TypeOf(true)
+//	case "JSON":
+//		return reflect.TypeOf(map[string]interface{}{})
+//	case "Map(String, Nullable(String))", "Map(String, String)", "Map(LowCardinality(String), String)", "Map(LowCardinality(String), Nullable(String))":
+//		return reflect.TypeOf(map[string]string{})
+//	case "Unknown":
+//		return reflect.TypeOf(UnknownType{})
+//	}
+//
+//	return nil
+//}
+
 // 'value': value of a field, from unmarshalled JSON
 // 'valueOrigin': name of the field (for error messages)
 func NewType(value any, valueOrigin string) (Type, error) {
@@ -428,7 +469,7 @@ func NewDefaultBoolAttribute() Attribute {
 }
 
 func (dt DateTimeType) String() string {
-	return []string{"DateTime64", "DateTime", "Invalid"}[dt]
+	return []string{"DateTime64", "DateTime", "datetime", "Invalid"}[dt]
 }
 
 func IsColumnAttributes(colName string) bool {

platform/clickhouse/table.go

@@ -106,10 +106,10 @@ func (t *Table) GetDateTimeType(ctx context.Context, fieldName string, dateInSch
 	if col, ok := t.Cols[fieldName]; ok {
 		typeName := col.Type.String()
 		// hasPrefix, not equal, because we can have DateTime64(3) and we want to catch it
-		if strings.HasPrefix(typeName, "DateTime64") {
+		if strings.HasPrefix(typeName, "datetime") {
 			return DateTime64
 		}
-		if strings.HasPrefix(typeName, "DateTime") {
+		if strings.HasPrefix(typeName, "date") {
 			return DateTime
 		}
 	}

platform/clickhouse/table_discovery.go

@@ -802,7 +802,8 @@ func (td *tableDiscovery) readTables(database string) (map[string]map[string]col
 		return map[string]map[string]columnMetadata{}, fmt.Errorf("database connection pool is nil, cannot describe tables")
 	}
 
-	rows, err := td.dbConnPool.Query(context.Background(), "SELECT table, name, type, comment FROM system.columns WHERE database = ?", database)
+	querySql := fmt.Sprintf("SELECT table_name, column_name, data_type, column_comment FROM information_schema.columns WHERE table_schema = '%s'", database)
+	rows, err := td.dbConnPool.Query(context.Background(), querySql)
 
 	if err != nil {
 		err = end_user_errors.GuessClickhouseErrorType(err).InternalDetails("reading list of columns from system.columns")
@@ -861,18 +862,18 @@ func (td *tableDiscovery) getTimestampFieldForClickHouse(database, table string)
 }
 
 func (td *tableDiscovery) tableComment(database, table string) (comment string) {
-	err := td.dbConnPool.QueryRow(context.Background(), "SELECT comment FROM system.tables WHERE database = ? and table = ?", database, table).Scan(&comment)
-	if err != nil {
-		logger.Error().Msgf("could not get table comment: %v", err)
-	}
+	//err := td.dbConnPool.QueryRow(context.Background(), "SELECT comment FROM system.tables WHERE database = ? and table = ?", database, table).Scan(&comment)
+	//if err != nil {
+	//	logger.Error().Msgf("could not get table comment: %v", err)
+	//}
 	return comment
 }
 
 func (td *tableDiscovery) createTableQuery(database, table string) (ddl string) {
-	err := td.dbConnPool.QueryRow(context.Background(), "SELECT create_table_query FROM system.tables WHERE database = ? and table = ? ", database, table).Scan(&ddl)
-	if err != nil {
-		logger.Error().Msgf("could not get create table statement: %v", err)
-	}
+	//err := td.dbConnPool.QueryRow(context.Background(), "SELECT create_table_query FROM system.tables WHERE database = ? and table = ? ", database, table).Scan(&ddl)
+	//if err != nil {
+	//	logger.Error().Msgf("could not get create table statement: %v", err)
+	//}
 	return ddl
 }