如何计算通过gob.Encode写入的每个记录的哈希值
我的目标是创建类似WAL日志的内容,并确保数据一致性,我使用了一些散列 对于每个编码记录,我有以下代码计算哈希:如何计算通过gob.Encode写入的每个记录的哈希值,go,hash,checksum,gob,Go,Hash,Checksum,Gob,我的目标是创建类似WAL日志的内容,并确保数据一致性,我使用了一些散列 对于每个编码记录,我有以下代码计算哈希: package dumper_test import ( "bufio" "bytes" "encoding/gob" "hash/crc32" "io" "testing" ) type Entry struct { A string B bool } func TestX(t *testing.T) {
package dumper_test
import (
"bufio"
"bytes"
"encoding/gob"
"hash/crc32"
"io"
"testing"
)
type Entry struct {
A string
B bool
}
func TestX(t *testing.T) {
gob.Register(Entry{})
// encoder part part
encHasher := crc32.New(crc32.MakeTable(crc32.Castagnoli))
w := &bytes.Buffer{}
enc := gob.NewEncoder(io.MultiWriter(w, encHasher))
entry := Entry{}
if err := enc.Encode(&entry); err != nil {
t.Fatal(err)
}
t.Logf("encHash: %d", encHasher.Sum32())
if err := enc.Encode(&entry); err != nil {
t.Fatal(err)
}
t.Logf("encHash: %d", encHasher.Sum32())
// decoder part
decHasher := crc32.New(crc32.MakeTable(crc32.Castagnoli))
r := bufio.NewReader(w)
dec := gob.NewDecoder(io.TeeReader(r, decHasher))
var decEntry Entry
if err := dec.Decode(&decEntry); err != nil {
t.Fatal(err)
}
t.Logf("decHash: %d", decHasher.Sum32())
if err := dec.Decode(&decEntry); err != nil {
t.Fatal(err)
}
t.Logf("decHash: %d", decHasher.Sum32())
if encHasher.Sum32() != decHasher.Sum32() {
t.Fail()
}
}
它产生以下输出:
=== RUN TestX
--- PASS: TestX (0.00s)
gob_test.go:29: encHash: 3843220763
gob_test.go:33: encHash: 1109147424
gob_test.go:43: decHash: 1109147424
gob_test.go:47: decHash: 1109147424
PASS
那么,当我按顺序解码条目时,为什么哈希是相同的呢?如何实现这一产出:
=== RUN TestX
--- PASS: TestX (0.00s)
gob_test.go:29: encHash: 3843220763
gob_test.go:33: encHash: 1109147424
gob_test.go:43: decHash: 3843220763
gob_test.go:47: decHash: 1109147424
PASS
沃尔日志是多余的:)为什么?gob提供安全还是什么?WAL=“提前写入日志”。所以你是说“写啊读日志”啊好吧