add map struct mapping

database.go

@@ -1 +0,0 @@
-package database

dbtool/dbtool.go

@@ -0,0 +1,135 @@
+package dbtool
+
+import (
+	"database/sql"
+	"errors"
+	"reflect"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// ScanToStruct - scan query rows to struct
+func ScanToStruct(rows *sql.Rows, ss interface{}) (err error) {
+	data, err := ResultToMap(rows)
+	if err != nil {
+		return err
+	}
+	if len(data) == 0 {
+		return nil
+	}
+	err = MapToStruct(data[0], ss)
+	return nil
+}
+
+func ScanToStructAll(rows *sql.Rows, ss interface{}) error {
+	sliceVal := reflect.Indirect(reflect.ValueOf(ss))
+	if sliceVal.Kind() != reflect.Slice && sliceVal.Kind() != reflect.Map {
+		return errors.New("need a pointer to a slice or a map")
+	}
+
+	data, err := ResultToMap(rows)
+	if err != nil {
+		return err
+	}
+
+	for i := range data {
+
+	}
+
+	return nil
+}
+
+func ResultToMap(r *sql.Rows) ([]map[string]interface{}, error) {
+	result := make([]map[string]interface{}, 0)
+	cols, err := r.Columns()
+	if err != nil {
+		return nil, err
+	}
+	vals := make([]sql.RawBytes, len(cols))
+	scans := make([]interface{}, len(vals))
+
+	for i := range vals {
+		scans[i] = &vals[i]
+	}
+
+	for r.Next() {
+		tmp := make(map[string]interface{})
+		err := r.Scan(scans...)
+		if err != nil {
+			return nil, err
+		}
+		for i, v := range vals {
+			tmp[cols[i]] = v
+		}
+		result = append(result, tmp)
+	}
+
+	return result, nil
+}
+
+func MapToStruct(data map[string]interface{}, out interface{}) error {
+	ss := reflect.ValueOf(out).Elem()
+	for i := 0; i < ss.NumField(); i++ {
+		tag := ss.Type().Field(i).Tag.Get("sql")
+		name := ss.Type().Field(i).Name
+		fname := strings.ToLower(name)
+		if len(tag) > 0 {
+			fname = tag
+		}
+
+		if fname == "-" {
+			continue
+		}
+
+		d, ok := data[fname]
+		if !ok {
+			continue
+		}
+
+		switch ss.Field(i).Interface().(type) {
+		case string:
+			ss.Field(i).SetString(string(d.(sql.RawBytes)))
+		case int, int8, int16, int32, int64:
+			str := string(d.(sql.RawBytes))
+			tmpi, err := strconv.ParseInt(str, 10, 64)
+			if err != nil {
+				return err
+			}
+			ss.Field(i).SetInt(tmpi)
+		case uint, uint8, uint16, uint32, uint64:
+			str := string(d.(sql.RawBytes))
+			tmpi, err := strconv.ParseUint(str, 10, 64)
+			if err != nil {
+				return err
+			}
+			ss.Field(i).SetUint(tmpi)
+		case bool:
+			str := string(d.(sql.RawBytes))
+			tmpb, err := strconv.ParseBool(str)
+			if err != nil {
+				return err
+			}
+			ss.Field(i).SetBool(tmpb)
+		case float32, float64:
+			str := string(d.(sql.RawBytes))
+			tmpf, err := strconv.ParseFloat(str, 64)
+			if err != nil {
+				return err
+			}
+			ss.Field(i).SetFloat(tmpf)
+		case time.Time:
+			str := string(d.(sql.RawBytes))
+			t, err := time.Parse(time.RFC3339, str)
+			if err != nil {
+				return err
+			}
+			ss.Field(i).Set(reflect.ValueOf(t))
+		default:
+			str := string(d.(sql.RawBytes))
+			ss.Field(i).Set(reflect.ValueOf(str))
+		}
+	}
+
+	return nil
+}

main.go

@@ -0,0 +1,36 @@
+package main
+
+import (
+	"database/sql"
+	"fmt"
+	"log"
+
+	_ "github.com/lib/pq"
+)
+
+// FileT - file db schema
+type FileT struct {
+	ID   string `db:"id"`
+	Name string `db:"name"`
+}
+
+func main() {
+	connStr := "postgres://postgres@localhost:5432/mystorage?sslmode=disable"
+	db, err := sql.Open("postgres", connStr)
+	handleError(err)
+
+	rows, err := db.Query(`select id, name from "storage"."files" where "tmp" = $1 and "trash" = $2 limit 2`, false, false)
+	handleError(err)
+
+	var id, name string
+	for rows.Next() {
+		rows.Scan(&id, &name)
+		fmt.Printf("id: %s, name: %s \n", id, name)
+	}
+}
+
+func handleError(err error) {
+	if err != nil {
+		log.Fatal(err)
+	}
+}