Попытка сделать фабрики репозиториев для абстрактных хранилищ данных.

Добавлено чтение конфигурации из файла.

db/redis.go

@@ -0,0 +1,144 @@
+package db
+
+import (
+	"bytes"
+	"compress/zlib"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"strings"
+
+	"github.com/mediocregopher/radix.v2/pool"
+	"github.com/mediocregopher/radix.v2/redis"
+	"github.com/mediocregopher/radix.v2/util"
+
+	"elyby/minecraft-skinsystem/model"
+	"elyby/minecraft-skinsystem/repositories"
+)
+
+type RedisFactory struct {
+	Host       string
+	Port       int
+	PoolSize   int
+	connection util.Cmder
+}
+
+func (f RedisFactory) CreateSkinsRepository() (repositories.SkinsRepository, error) {
+	connection, err := f.getConnection()
+	if err != nil {
+		return nil, err
+	}
+
+	return &redisDb{connection}, nil
+}
+
+func (f RedisFactory) CreateCapesRepository() (repositories.CapesRepository, error) {
+	panic("capes repository not supported for this storage type")
+}
+
+func (f RedisFactory) getConnection() (util.Cmder, error) {
+	if f.connection == nil {
+		if f.Host == "" {
+			return nil, &ParamRequired{"host"}
+		}
+
+		if f.Port == 0 {
+			return nil, &ParamRequired{"port"}
+		}
+
+		var conn util.Cmder
+		var err error
+		addr := fmt.Sprintf("%s:%d", f.Host, f.Port)
+		if f.PoolSize > 1 {
+			conn, err = pool.New("tcp", addr, f.PoolSize)
+		} else {
+			conn, err = redis.Dial("tcp", addr)
+		}
+
+		if err != nil {
+			return nil, err
+		}
+
+		f.connection = conn
+	}
+
+	return f.connection, nil
+}
+
+type redisDb struct {
+	conn util.Cmder
+}
+
+const accountIdToUsernameKey string = "hash:username-to-account-id"
+
+func (db *redisDb) FindByUsername(username string) (model.Skin, error) {
+	var record model.Skin
+	if username == "" {
+		return record, &SkinNotFoundError{username}
+	}
+
+	redisKey := buildKey(username)
+	response := db.conn.Cmd("GET", redisKey)
+	if response.IsType(redis.Nil) {
+		return record, &SkinNotFoundError{username}
+	}
+
+	encodedResult, err := response.Bytes()
+	if err == nil {
+		result, err := zlibDecode(encodedResult)
+		if err != nil {
+			log.Println("Cannot uncompress zlib for key " + redisKey) // TODO: replace with valid error
+			return record, err
+		}
+
+		err = json.Unmarshal(result, &record)
+		if err != nil {
+			log.Println("Cannot decode record data for key" + redisKey) // TODO: replace with valid error
+			return record, nil
+		}
+
+		record.OldUsername = record.Username
+	}
+
+	return record, nil
+}
+
+func (db *redisDb) FindByUserId(id int) (model.Skin, error) {
+	response := db.conn.Cmd("HGET", accountIdToUsernameKey, id)
+	if response.IsType(redis.Nil) {
+		return model.Skin{}, SkinNotFoundError{"unknown"}
+	}
+
+	username, _ := response.Str()
+
+	return db.FindByUsername(username)
+}
+
+func buildKey(username string) string {
+	return "username:" + strings.ToLower(username)
+}
+
+//noinspection GoUnusedFunction
+func zlibEncode(str []byte) []byte {
+	var buff bytes.Buffer
+	writer := zlib.NewWriter(&buff)
+	writer.Write(str)
+	writer.Close()
+
+	return buff.Bytes()
+}
+
+func zlibDecode(bts []byte) ([]byte, error) {
+	buff := bytes.NewReader(bts)
+	reader, readError := zlib.NewReader(buff)
+	if readError != nil {
+		return nil, readError
+	}
+
+	resultBuffer := new(bytes.Buffer)
+	io.Copy(resultBuffer, reader)
+	reader.Close()
+
+	return resultBuffer.Bytes(), nil
+}