wechaty/go-wechaty

package storage

import (
    "encoding/json"
    helper_functions "github.com/wechaty/go-wechaty/wechaty-puppet/helper"
    "io/ioutil"
    "os"
    "path/filepath"
    "strings"
)

type FileStorage struct {
    absFileName string
}

func NewFileStorage(absFileName string) (*FileStorage, error) {
    absFileName, err := handleAbsFileName(absFileName)
    if err != nil {
        return nil, err
    }
    return &FileStorage{absFileName: absFileName}, nil
}

func (f *FileStorage) Save(payload map[string]interface{}) error {
    jsonBytes, err := json.Marshal(payload)
    if err != nil {
        return err
    }
    return ioutil.WriteFile(f.absFileName, jsonBytes, os.ModePerm)
}

func (f *FileStorage) Load() (map[string]interface{}, error) {
    if !helper_functions.FileExists(f.absFileName) {
        return map[string]interface{}{}, nil
    }
    file, err := os.Open(f.absFileName)
    if err != nil {
        return nil, err
    }
    result := map[string]interface{}{}
    decoder := json.NewDecoder(file)
    decoder.UseNumber()
    if err := decoder.Decode(&result); err != nil {
        return nil, err
    }
    return result, nil
}

func (f *FileStorage) Destroy() error {
    return os.Remove(f.absFileName)
}

func handleAbsFileName(absFileName string) (string, error) {
    const suffix = ".memory-card.json"
    if !strings.HasSuffix(absFileName, suffix) {
        absFileName = absFileName + suffix
    }
    if !filepath.IsAbs(absFileName) {
        dir, err := os.Getwd()
        if err != nil {
            return "", err
        }
        absFileName = filepath.Join(dir, absFileName)
    }
    return absFileName, nil
}