go-mockid/kvdb/kvdb.go

132 lines
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2020-09-16 22:34:25 +00:00
package kvdb
import (
"encoding/json"
"errors"
"fmt"
"io/ioutil"
"os"
"path/filepath"
"strconv"
"strings"
)
type KVDB struct {
Prefix string
Ext string
}
func (kv *KVDB) Load(
keyif interface{},
typ ...interface{},
) (value interface{}, ok bool, err error) {
key, _ := keyif.(string)
if "" == key || strings.Contains(key, "..") || strings.ContainsAny(key, "$#!:| \n") {
return nil, false, nil
}
userFile := filepath.Join(kv.Prefix, key+"."+kv.Ext)
fmt.Println("Debug user file:", userFile)
b, err := ioutil.ReadFile(userFile)
if nil != err {
if os.IsNotExist(err) {
return nil, false, nil
}
fmt.Println("kvdb debug read:", err)
return nil, false, errors.New("database read failed")
}
ok = true
value = b
if 1 == len(typ) {
err := json.Unmarshal(b, typ[0])
if nil != err {
return nil, false, err
}
value = typ[0]
} else if len(b) > 0 && '"' == b[0] {
var str string
err := json.Unmarshal(b, &str)
if nil == err {
value = str
}
}
return value, ok, nil
}
func (kv *KVDB) Store(keyif interface{}, value interface{}) (err error) {
key, _ := keyif.(string)
if "" == key || strings.Contains(key, "..") || strings.ContainsAny(key, "$#! \n") {
return errors.New("invalid key name")
}
keypath := filepath.Join(kv.Prefix, key+"."+kv.Ext)
f, err := os.Open(keypath)
if nil == err {
s, err := f.Stat()
if nil != err {
// if we can open, we should be able to stat
return errors.New("database connection failure")
}
ts := strconv.FormatInt(s.ModTime().Unix(), 10)
bakpath := filepath.Join(kv.Prefix, key+"."+ts+"."+kv.Ext)
if err := os.Rename(keypath, bakpath); nil != err {
// keep the old record as a backup
return errors.New("database write failure")
}
}
var b []byte
switch v := value.(type) {
case []byte:
b = v
case string:
b, _ = json.Marshal(v)
default:
fmt.Println("kvdb: not []byte or string:", v)
jsonb, err := json.Marshal(v)
if nil != err {
return err
}
b = jsonb
}
if err := ioutil.WriteFile(
keypath,
b,
os.FileMode(0600),
); nil != err {
fmt.Println("write failure:", err)
return errors.New("database write failed")
}
return nil
}
func (kv *KVDB) Delete(keyif interface{}) (err error) {
key, _ := keyif.(string)
if "" == key || strings.Contains(key, "..") || strings.ContainsAny(key, "$#! \n") {
return errors.New("invalid key name")
}
keypath := filepath.Join(kv.Prefix, key+"."+kv.Ext)
f, err := os.Open(keypath)
if nil == err {
s, err := f.Stat()
if nil != err {
return errors.New("database connection failure")
}
ts := strconv.FormatInt(s.ModTime().Unix(), 64)
if err := os.Rename(keypath, filepath.Join(kv.Prefix, key+"."+ts+"."+kv.Ext)); nil != err {
return errors.New("database connection failure")
}
}
return nil
}
func (kv *KVDB) Vacuum() (err error) {
return nil
}