frostfs-s3-gw/pkg/s3select/sql/record.go

141 lines
3.3 KiB
Go

/*
* MinIO Cloud Storage, (C) 2019 MinIO, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package sql
import (
"fmt"
"io"
"github.com/minio/simdjson-go"
)
// SelectObjectFormat specifies the format of the underlying data
type SelectObjectFormat int
const (
// SelectFmtUnknown - unknown format (default value)
SelectFmtUnknown SelectObjectFormat = iota
// SelectFmtCSV - CSV format
SelectFmtCSV
// SelectFmtJSON - JSON format
SelectFmtJSON
// SelectFmtSIMDJSON - SIMD JSON format
SelectFmtSIMDJSON
// SelectFmtParquet - Parquet format
SelectFmtParquet
)
// WriteCSVOpts - encapsulates options for Select CSV output
type WriteCSVOpts struct {
FieldDelimiter rune
Quote rune
QuoteEscape rune
AlwaysQuote bool
}
// Record - is a type containing columns and their values.
type Record interface {
Get(name string) (*Value, error)
// Set a value.
// Can return a different record type.
Set(name string, value *Value) (Record, error)
WriteCSV(writer io.Writer, opts WriteCSVOpts) error
WriteJSON(writer io.Writer) error
// Clone the record and if possible use the destination provided.
Clone(dst Record) Record
Reset()
// Returns underlying representation
Raw() (SelectObjectFormat, interface{})
// Replaces the underlying data
Replace(k interface{}) error
}
// IterToValue converts a simdjson Iter to its underlying value.
// Objects are returned as simdjson.Object
// Arrays are returned as []interface{} with parsed values.
func IterToValue(iter simdjson.Iter) (interface{}, error) {
switch iter.Type() {
case simdjson.TypeString:
v, err := iter.String()
if err != nil {
return nil, err
}
return v, nil
case simdjson.TypeFloat:
v, err := iter.Float()
if err != nil {
return nil, err
}
return v, nil
case simdjson.TypeInt:
v, err := iter.Int()
if err != nil {
return nil, err
}
return v, nil
case simdjson.TypeUint:
v, err := iter.Int()
if err != nil {
// Can't fit into int, convert to float.
v, err := iter.Float()
return v, err
}
return v, nil
case simdjson.TypeBool:
v, err := iter.Bool()
if err != nil {
return nil, err
}
return v, nil
case simdjson.TypeObject:
obj, err := iter.Object(nil)
if err != nil {
return nil, err
}
return *obj, err
case simdjson.TypeArray:
arr, err := iter.Array(nil)
if err != nil {
return nil, err
}
iter := arr.Iter()
var dst []interface{}
var next simdjson.Iter
for {
typ, err := iter.AdvanceIter(&next)
if err != nil {
return nil, err
}
if typ == simdjson.TypeNone {
break
}
v, err := IterToValue(next)
if err != nil {
return nil, err
}
dst = append(dst, v)
}
return dst, err
case simdjson.TypeNull:
return nil, nil
}
return nil, fmt.Errorf("IterToValue: unknown JSON type: %s", iter.Type().String())
}