add file adapter.

internal/config/session.go

@@ -9,6 +9,8 @@ type Session struct {
 	Password        string
 	AdminPassword   string
 	ImplicitHosting bool
+	DatabaseAdapter string
+	FilePath        string
 }
 
 func (Session) Init(cmd *cobra.Command) error {
@@ -27,6 +29,16 @@ func (Session) Init(cmd *cobra.Command) error {
 		return err
 	}
 
+	cmd.PersistentFlags().String("database_adapter", "file", "choose database adapter for members")
+	if err := viper.BindPFlag("database_adapter", cmd.PersistentFlags().Lookup("database_adapter")); err != nil {
+		return err
+	}
+
+	cmd.PersistentFlags().String("file_path", "/home/neko/members.json", "file adapter: specify file path")
+	if err := viper.BindPFlag("file_path", cmd.PersistentFlags().Lookup("file_path")); err != nil {
+		return err
+	}
+
 	return nil
 }
 
@@ -34,4 +46,6 @@ func (s *Session) Set() {
 	s.Password = viper.GetString("password")
 	s.AdminPassword = viper.GetString("password_admin")
 	s.ImplicitHosting = viper.GetBool("implicit_hosting")
+	s.DatabaseAdapter = viper.GetString("database_adapter")
+	s.FilePath = viper.GetString("file_path")
 }

internal/session/database/file/adapter.go

@@ -0,0 +1,127 @@
+package file
+
+import (
+    "encoding/json"
+    "io/ioutil"
+	"os"
+	"fmt"
+	"sync"
+
+	"github.com/rs/zerolog/log"
+
+	"demodesk/neko/internal/types"
+)
+
+func New(file string) types.MembersDatabase {
+	return &MembersDatabaseCtx{
+		file: file,
+		mu:   sync.Mutex{},
+	}
+}
+
+type MembersDatabaseCtx struct {
+	file string
+	mu   sync.Mutex
+}
+
+func (manager *MembersDatabaseCtx) Insert(id string, profile types.MemberProfile) error {
+	manager.mu.Lock()
+	defer manager.mu.Unlock()
+
+	profiles, err := manager.deserialize()
+	if err != nil {
+		return err
+	}
+
+	_, ok := profiles[id]
+	if ok {
+		return fmt.Errorf("Member ID already exists.")
+	}
+
+	profiles[id] = profile
+
+	return manager.serialize(profiles)
+}
+
+func (manager *MembersDatabaseCtx) Update(id string, profile types.MemberProfile) error {
+	manager.mu.Lock()
+	defer manager.mu.Unlock()
+
+	profiles, err := manager.deserialize()
+	if err != nil {
+		return err
+	}
+
+	_, ok := profiles[id]
+	if !ok {
+		return fmt.Errorf("Member ID does not exist.")
+	}
+
+	profiles[id] = profile
+
+	return manager.serialize(profiles)
+}
+
+func (manager *MembersDatabaseCtx) Delete(id string) error {
+	manager.mu.Lock()
+	defer manager.mu.Unlock()
+
+	profiles, err := manager.deserialize()
+	if err != nil {
+		return err
+	}
+
+	_, ok := profiles[id]
+	if !ok {
+		return fmt.Errorf("Member ID does not exist.")
+	}
+
+	delete(profiles, id)
+
+	return manager.serialize(profiles)
+}
+
+func (manager *MembersDatabaseCtx) Select() map[string]types.MemberProfile {
+	manager.mu.Lock()
+	defer manager.mu.Unlock()
+
+	profiles, err := manager.deserialize()
+	if err != nil {
+		// TODO: Refactor.
+		log.Panic().Err(err).Msg("could not read members file")
+	}
+
+	return profiles
+}
+
+func (manager *MembersDatabaseCtx) deserialize() (map[string]types.MemberProfile, error) {
+	file, err := os.OpenFile(manager.file, os.O_RDONLY|os.O_CREATE, os.ModePerm)
+	if err != nil {
+		return nil, err
+	}
+
+    raw, err := ioutil.ReadAll(file)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(raw) == 0 {
+		return map[string]types.MemberProfile{}, nil
+	}
+
+	var profiles map[string]types.MemberProfile
+	if err := json.Unmarshal([]byte(raw), &profiles); err != nil {
+		return nil, err
+	}
+
+	return profiles, nil
+}
+
+func (manager *MembersDatabaseCtx) serialize(data map[string]types.MemberProfile) error {
+	raw, err := json.Marshal(data)
+	if err != nil {
+		return err
+	}
+
+	return ioutil.WriteFile(manager.file, raw, os.ModePerm)
+}

internal/session/database/manager.go

@@ -2,16 +2,16 @@ package database
 
 import (
 	"demodesk/neko/internal/session/database/dummy"
+	"demodesk/neko/internal/session/database/file"
 	"demodesk/neko/internal/session/database/object"
 	"demodesk/neko/internal/types"
 	"demodesk/neko/internal/config"
 )
 
 func New(config *config.Session) types.MembersDatabase {
-	// TODO: Load from config.
-	adapter := "object"
-
-	switch adapter {
+	switch config.DatabaseAdapter {
+	case "file":
+		return file.New(config.FilePath)
 	case "object":
 		return object.New()
 	case "dummy":