Get SHA256 from file in golang

getChecksum.go

package main

import (
	"bufio"
	"crypto/sha256"
	"encoding/hex"
	"fmt"
	"os"
)

func main() {
	uploadedFile, _ := os.Open(filename)
	fileStat, _ := uploadedFile.Stat()
	bytes := make([]byte, fileStat.Size())
	buffer := bufio.NewReader(uploadedFile)
	_, err := buffer.Read(bytes)
	if err != nil {
		panic(err)
	}
	sha256sumtext := sha256.Sum256(bytes)
	fmt.Printf("%s", hex.EncodeToString(sha256sumtext[:]))
}