mirror of https://github.com/status-im/op-geth.git
88 lines
2.5 KiB
Go
88 lines
2.5 KiB
Go
// Copyright 2018 The go-ethereum Authors
|
|
// This file is part of the go-ethereum library.
|
|
//
|
|
// The go-ethereum library is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU Lesser General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// The go-ethereum library is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU Lesser General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Lesser General Public License
|
|
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
package storage
|
|
|
|
import "errors"
|
|
|
|
var (
|
|
// ErrZeroKey is returned if an attempt was made to inset a 0-length key.
|
|
ErrZeroKey = errors.New("0-length key")
|
|
|
|
// ErrNotFound is returned if an unknown key is attempted to be retrieved.
|
|
ErrNotFound = errors.New("not found")
|
|
)
|
|
|
|
type Storage interface {
|
|
// Put stores a value by key. 0-length keys results in noop.
|
|
Put(key, value string)
|
|
|
|
// Get returns the previously stored value, or an error if the key is 0-length
|
|
// or unknown.
|
|
Get(key string) (string, error)
|
|
|
|
// Del removes a key-value pair. If the key doesn't exist, the method is a noop.
|
|
Del(key string)
|
|
}
|
|
|
|
// EphemeralStorage is an in-memory storage that does
|
|
// not persist values to disk. Mainly used for testing
|
|
type EphemeralStorage struct {
|
|
data map[string]string
|
|
namespace string
|
|
}
|
|
|
|
// Put stores a value by key. 0-length keys results in noop.
|
|
func (s *EphemeralStorage) Put(key, value string) {
|
|
if len(key) == 0 {
|
|
return
|
|
}
|
|
s.data[key] = value
|
|
}
|
|
|
|
// Get returns the previously stored value, or an error if the key is 0-length
|
|
// or unknown.
|
|
func (s *EphemeralStorage) Get(key string) (string, error) {
|
|
if len(key) == 0 {
|
|
return "", ErrZeroKey
|
|
}
|
|
if v, ok := s.data[key]; ok {
|
|
return v, nil
|
|
}
|
|
return "", ErrNotFound
|
|
}
|
|
|
|
// Del removes a key-value pair. If the key doesn't exist, the method is a noop.
|
|
func (s *EphemeralStorage) Del(key string) {
|
|
delete(s.data, key)
|
|
}
|
|
|
|
func NewEphemeralStorage() Storage {
|
|
s := &EphemeralStorage{
|
|
data: make(map[string]string),
|
|
}
|
|
return s
|
|
}
|
|
|
|
// NoStorage is a dummy construct which doesn't remember anything you tell it
|
|
type NoStorage struct{}
|
|
|
|
func (s *NoStorage) Put(key, value string) {}
|
|
func (s *NoStorage) Del(key string) {}
|
|
func (s *NoStorage) Get(key string) (string, error) {
|
|
return "", errors.New("I forgot")
|
|
}
|