mirror of https://github.com/minio/minio.git
94 lines
2.4 KiB
Go
94 lines
2.4 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() (sql.Record, error) {
|
||
|
parquetRecord, err := r.file.Read()
|
||
|
if err != nil {
|
||
|
if err != io.EOF {
|
||
|
return nil, errParquetParsingError(err)
|
||
|
}
|
||
|
|
||
|
return nil, err
|
||
|
}
|
||
|
|
||
|
record := json.NewRecord()
|
||
|
for name, v := range parquetRecord {
|
||
|
var value *sql.Value
|
||
|
switch v.Type {
|
||
|
case parquetgen.Type_BOOLEAN:
|
||
|
value = sql.NewBool(v.Value.(bool))
|
||
|
case parquetgen.Type_INT32:
|
||
|
value = sql.NewInt(int64(v.Value.(int32)))
|
||
|
case parquetgen.Type_INT64:
|
||
|
value = sql.NewInt(v.Value.(int64))
|
||
|
case parquetgen.Type_FLOAT:
|
||
|
value = sql.NewFloat(float64(v.Value.(float32)))
|
||
|
case parquetgen.Type_DOUBLE:
|
||
|
value = sql.NewFloat(v.Value.(float64))
|
||
|
case parquetgen.Type_INT96, parquetgen.Type_BYTE_ARRAY, parquetgen.Type_FIXED_LEN_BYTE_ARRAY:
|
||
|
value = sql.NewString(string(v.Value.([]byte)))
|
||
|
default:
|
||
|
return nil, errParquetParsingError(nil)
|
||
|
}
|
||
|
|
||
|
if err = record.Set(name, value); err != nil {
|
||
|
return nil, errParquetParsingError(err)
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return record, nil
|
||
|
}
|
||
|
|
||
|
// 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
|
||
|
}
|