mirror of https://github.com/minio/minio.git
104 lines
2.6 KiB
Go
104 lines
2.6 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 parquet
|
|
|
|
import (
|
|
"io"
|
|
|
|
"github.com/minio/minio/pkg/s3select/json"
|
|
"github.com/minio/minio/pkg/s3select/sql"
|
|
parquetgo "github.com/minio/parquet-go"
|
|
parquetgen "github.com/minio/parquet-go/gen-go/parquet"
|
|
)
|
|
|
|
// Reader - Parquet record reader for S3Select.
|
|
type Reader struct {
|
|
args *ReaderArgs
|
|
file *parquetgo.File
|
|
}
|
|
|
|
// Read - reads single record.
|
|
func (r *Reader) Read() (rec sql.Record, rerr error) {
|
|
parquetRecord, err := r.file.Read()
|
|
if err != nil {
|
|
if err != io.EOF {
|
|
return nil, errParquetParsingError(err)
|
|
}
|
|
|
|
return nil, err
|
|
}
|
|
|
|
record := json.NewRecord()
|
|
f := func(name string, v parquetgo.Value) bool {
|
|
if v.Value == nil {
|
|
if err := record.Set(name, sql.FromNull()); err != nil {
|
|
rerr = errParquetParsingError(err)
|
|
}
|
|
return rerr == nil
|
|
}
|
|
|
|
var value *sql.Value
|
|
switch v.Type {
|
|
case parquetgen.Type_BOOLEAN:
|
|
value = sql.FromBool(v.Value.(bool))
|
|
case parquetgen.Type_INT32:
|
|
value = sql.FromInt(int64(v.Value.(int32)))
|
|
case parquetgen.Type_INT64:
|
|
value = sql.FromInt(int64(v.Value.(int64)))
|
|
case parquetgen.Type_FLOAT:
|
|
value = sql.FromFloat(float64(v.Value.(float32)))
|
|
case parquetgen.Type_DOUBLE:
|
|
value = sql.FromFloat(v.Value.(float64))
|
|
case parquetgen.Type_INT96, parquetgen.Type_BYTE_ARRAY, parquetgen.Type_FIXED_LEN_BYTE_ARRAY:
|
|
value = sql.FromString(string(v.Value.([]byte)))
|
|
default:
|
|
rerr = errParquetParsingError(nil)
|
|
return false
|
|
}
|
|
|
|
if err = record.Set(name, value); err != nil {
|
|
rerr = errParquetParsingError(err)
|
|
}
|
|
return rerr == nil
|
|
}
|
|
|
|
parquetRecord.Range(f)
|
|
return record, rerr
|
|
}
|
|
|
|
// Close - closes underlaying readers.
|
|
func (r *Reader) Close() error {
|
|
return r.file.Close()
|
|
}
|
|
|
|
// NewReader - creates new Parquet reader using readerFunc callback.
|
|
func NewReader(getReaderFunc func(offset, length int64) (io.ReadCloser, error), args *ReaderArgs) (*Reader, error) {
|
|
file, err := parquetgo.Open(getReaderFunc, nil)
|
|
if err != nil {
|
|
if err != io.EOF {
|
|
return nil, errParquetParsingError(err)
|
|
}
|
|
|
|
return nil, err
|
|
}
|
|
|
|
return &Reader{
|
|
args: args,
|
|
file: file,
|
|
}, nil
|
|
}
|