forked from xitongsys/parquet-go-source
/
hdfs_flat.go
73 lines (67 loc) · 1.66 KB
/
hdfs_flat.go
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package main
import (
"log"
"github.com/xitongsys/parquet-go-source/hdfs"
"github.com/xitongsys/parquet-go/reader"
"github.com/xitongsys/parquet-go/writer"
)
type Student struct {
Name string `parquet:"name=name, type=UTF8"`
Age int32 `parquet:"name=age, type=INT32"`
Id int64 `parquet:"name=id, type=INT64"`
Weight float32 `parquet:"name=weight, type=FLOAT"`
Sex bool `parquet:"name=sex, type=BOOLEAN"`
}
func main() {
var err error
//write
fw, err := hdfs.NewHdfsFileWriter([]string{"localhost:9000"}, "root", "/flat.parquet")
if err != nil {
log.Println("Can't create hdfs file", err)
return
}
pw, err := writer.NewParquetWriter(fw, new(Student), 4)
if err != nil {
log.Println("Can't create parquet writer", err)
return
}
num := 10
for i := 0; i < num; i++ {
stu := Student{
Name: "StudentName",
Age: int32(20 + i%5),
Id: int64(i),
Weight: float32(50.0 + float32(i)*0.1),
Sex: bool(i%2 == 0),
}
if err = pw.Write(stu); err != nil {
log.Println("Write error", err)
}
}
if err = pw.WriteStop(); err != nil {
log.Println("WriteStop err", err)
}
log.Println("Write Finished")
fw.Close()
///read
fr, err := hdfs.NewHdfsFileReader([]string{"localhost:9000"}, "", "/flat.parquet")
if err != nil {
log.Println("Can't open hdfs file", err)
return
}
pr, err := reader.NewParquetReader(fr, new(Student), 4)
if err != nil {
log.Println("Can't create parquet reader", err)
return
}
num = int(pr.GetNumRows())
for i := 0; i < num; i++ {
stus := make([]Student, 1)
if err = pr.Read(&stus); err != nil {
log.Println("Read error", err)
}
log.Println(stus)
}
pr.ReadStop()
fr.Close()
}