feat(storage): 为 LevelDB 添加自定义比较器

- 实现了 LevelDBComparator 结构体和 Compare 方法
- 添加了自定义的 mycompare 方法，支持多种数据类型的比较
- 新增了 utils/constant.go 文件，定义了常量用于索引和类型标识

api/collection.go

@@ -1,10 +1,12 @@
 package api
 
 import (
+	"fmt"
 	"sync"
 
 	"git.pyer.club/kingecg/godocdb/document"
 	"git.pyer.club/kingecg/godocdb/index" // "fmt"
+	"go.mongodb.org/mongo-driver/bson/primitive"
 )
 
 // "go.mongodb.org/mongo-driver/bson"
@@ -44,9 +46,18 @@ func NewCollection(name string, storagePath string) (*Collection, error) {
 func (coll *Collection) InsertOne(doc interface{}) error {
 	// 自动生成文档ID
 	// docID := generateID()
+	docMap, ok := doc.(map[string]interface{})
+	if !ok {
+		return fmt.Errorf("document must be a map[string]interface{}")
+	}
+	docID, exists := docMap["_id"].(primitive.ObjectID)
+	if !exists {
+		docID = primitive.NewObjectID()
+		docMap["_id"] = docID
+	}
 
 	// 将collection信息传递给文档管理层和索引管理层
-	if err := coll.documentStore.StoreDocument(coll.name, "", doc); err != nil {
+	if err := coll.documentStore.StoreDocument(coll.name, docID.String(), doc); err != nil {
 		return err
 	}
 

api/index.go

@@ -0,0 +1,8 @@
+package api
+
+import "git.pyer.club/kingecg/godocdb/index"
+
+type Index struct {
+	metadata index.IndexMetadata
+	store    *index.IndexStore
+}

document/document.go

@@ -32,7 +32,7 @@ func NewDocumentStore(storeName string) (*DocumentStore, error) {
 		storage.Close()
 		return nil, fmt.Errorf("failed to create index store: %v", err)
 	}
-	if errCreate := is.CreateIndex("default_index", index.NonUnique, []string{"_id"}, []index.IndexSortOrder{index.Ascending}); errCreate != nil {
+	if _, errCreate := is.CreateIndex("default_index", index.NonUnique, []string{"_id"}, []index.IndexSortOrder{index.Ascending}); errCreate != nil {
 		return nil, errCreate
 	}
 
@@ -107,7 +107,7 @@ func (ds *DocumentStore) StoreDocument(collection string, id string, doc interfa
 	// 创建默认索引（如果不存在）
 	if _, err := ds.indexStore.GetIndexMetadata("default_index"); err != nil {
 		// 如果索引不存在，创建默认索引
-		if errCreate := ds.indexStore.CreateIndex("default_index", index.NonUnique, []string{"_id"}, nil); errCreate != nil {
+		if _, errCreate := ds.indexStore.CreateIndex("default_index", index.NonUnique, []string{"_id"}, nil); errCreate != nil {
 			return errCreate
 		}
 	}

index/index.go

@@ -62,13 +62,13 @@ func NewIndexStore(storeName string) (*IndexStore, error) {
 }
 
 // CreateIndex 创建索引
-func (is *IndexStore) CreateIndex(indexName string, indexType IndexType, keyFields []string, sortOrders []IndexSortOrder) error {
+func (is *IndexStore) CreateIndex(indexName string, indexType IndexType, keyFields []string, sortOrders []IndexSortOrder) (*IndexMetadata, error) {
 	is.mu.Lock()
 	defer is.mu.Unlock()
 
 	// 验证keyFields和sortOrders长度一致
 	if len(keyFields) != len(sortOrders) {
-		return fmt.Errorf("keyFields and sortOrders must have the same length")
+		return nil, fmt.Errorf("keyFields and sortOrders must have the same length")
 	}
 
 	// 存储索引元数据
@@ -82,25 +82,26 @@ func (is *IndexStore) CreateIndex(indexName string, indexType IndexType, keyFiel
 
 	data, err := bson.Marshal(metadata)
 	if err != nil {
-		return fmt.Errorf("failed to marshal index metadata: %v", err)
+		return nil, fmt.Errorf("failed to marshal index metadata: %v", err)
 	}
 
 	key := []byte(fmt.Sprintf("indexes:metadata:%s", indexName))
 	if err := is.storage.Put(key, data); err != nil {
-		return err
+		return nil, err
 	}
+	return &metadata, nil
 
-	// 初始化索引结构
-	index := make(map[string]string)
+	// // 初始化索引结构
+	// index := make(map[string]string)
 
-	// 存储初始索引结构
-	indexKey := fmt.Sprintf("indexes:data:%s", indexName)
-	indexData, err := bson.Marshal(index)
-	if err != nil {
-		return fmt.Errorf("failed to marshal index data: %v", err)
-	}
+	// // 存储初始索引结构
+	// indexKey := fmt.Sprintf("indexes:data:%s", indexName)
+	// indexData, err := bson.Marshal(index)
+	// if err != nil {
+	// 	return fmt.Errorf("failed to marshal index data: %v", err)
+	// }
 
-	return is.storage.Put([]byte(indexKey), indexData)
+	// return is.storage.Put([]byte(indexKey), indexData)
 }
 
 // UpdateIndex 在指定collection下更新索引

index/index_test.go

@@ -24,7 +24,7 @@ func TestIndexStore(t *testing.T) {
 	keyFields := []string{"name"}
 
 	// 测试创建索引（默认升序）
-	if err := is.CreateIndex(indexName, NonUnique, keyFields, []IndexSortOrder{Ascending}); err != nil {
+	if _, err := is.CreateIndex(indexName, NonUnique, keyFields, []IndexSortOrder{Ascending}); err != nil {
 		t.Errorf("CreateIndex failed: %v", err)
 	}
 
@@ -67,7 +67,7 @@ func TestCompositeIndex(t *testing.T) {
 	keyFields := []string{"name", "age"}
 
 	// 创建复合索引（默认升序）
-	if err := is.CreateIndex(indexName, NonUnique, keyFields, []IndexSortOrder{Ascending, Ascending}); err != nil {
+	if _, err := is.CreateIndex(indexName, NonUnique, keyFields, []IndexSortOrder{Ascending, Ascending}); err != nil {
 		t.Errorf("CreateIndex failed: %v", err)
 	}
 
@@ -99,7 +99,7 @@ func TestIndexSortOrder(t *testing.T) {
 	keyFields := []string{"timestamp"}
 
 	// 测试创建升序索引
-	if err := is.CreateIndex(indexName, NonUnique, keyFields, []IndexSortOrder{Ascending}); err != nil {
+	if _, err := is.CreateIndex(indexName, NonUnique, keyFields, []IndexSortOrder{Ascending}); err != nil {
 		t.Errorf("CreateIndex failed: %v", err)
 	}
 
@@ -115,7 +115,7 @@ func TestIndexSortOrder(t *testing.T) {
 
 	// 测试创建降序索引
 	indexNameDesc := "sorted_index_desc"
-	if err := is.CreateIndex(indexNameDesc, NonUnique, keyFields, []IndexSortOrder{Descending}); err != nil {
+	if _, err := is.CreateIndex(indexNameDesc, NonUnique, keyFields, []IndexSortOrder{Descending}); err != nil {
 		t.Errorf("CreateIndex failed: %v", err)
 	}
 
@@ -147,7 +147,7 @@ func TestCompositeIndexSortOrders(t *testing.T) {
 	sortOrders := []IndexSortOrder{Descending, Ascending}
 
 	// 创建复合索引
-	if err := is.CreateIndex(indexName, NonUnique, keyFields, sortOrders); err != nil {
+	if _, err := is.CreateIndex(indexName, NonUnique, keyFields, sortOrders); err != nil {
 		t.Errorf("CreateIndex failed: %v", err)
 	}
 
@@ -206,7 +206,7 @@ func TestConcurrentIndexOperations(t *testing.T) {
 			indexName := fmt.Sprintf("concurrent_index_%d", i)
 
 			// 创建索引（默认升序）
-			if err := is.CreateIndex(indexName, NonUnique, []string{"name"}, []IndexSortOrder{Ascending}); err != nil {
+			if _, err := is.CreateIndex(indexName, NonUnique, []string{"name"}, []IndexSortOrder{Ascending}); err != nil {
 				t.Errorf("CreateIndex failed: %v", err)
 			}
 

storage/leveldb.go

@@ -2,6 +2,10 @@ package storage
 
 import (
 	"bytes"
+	"strconv"
+	"strings"
+
+	"git.pyer.club/kingecg/godocdb/utils"
 	"github.com/syndtr/goleveldb/leveldb"
 )
 
@@ -56,4 +60,83 @@ func (s *LevelDBStorage) Scan(prefix []byte) (keys [][]byte, values [][]byte, er
 // Close 关闭数据库连接
 func (s *LevelDBStorage) Close() {
 	s.db.Close()
-}
+}
+
+type LevelDBComparator struct {
+}
+
+func (c *LevelDBComparator) Compare(a, b []byte) int {
+	ka := string(a)
+	kb := string(b)
+
+	if strings.HasPrefix(ka, utils.Prefix_Index_Data) && strings.HasPrefix(kb, utils.Prefix_Index_Data) {
+		kas := strings.Split(ka, utils.Separator_Key)
+		kab := strings.Split(kb, utils.Separator_Key)
+		if kas[1] == kab[1] {
+			typestr := kas[2]
+			orderstr := kas[3]
+			kav := kas[4]
+			kbv := kab[4]
+			return c.mycompare(typestr, orderstr, kav, kbv)
+		}
+
+	}
+	return bytes.Compare(a, b)
+}
+
+// LevelDBComparator 的 mycompare 方法用于按照指定类型和排序规则比较两个字符串
+// 参数:
+//   types: 比较类型字符串（每个字符对应一种类型）
+//   orders: 排序方向字符串（每个字符对应升序/降序）
+//   a: 待比较的第一个字符串
+//   b: 待比较的第二个字符串
+// 返回值:
+//   0: 相等
+//  -1: a 小于 b
+//   1: a 大于 b
+// 
+// 支持的比较类型:
+//   Type_String: 字符串比较
+//   Type_Int: 整数比较（当前未实现）
+//   Type_Date: 日期比较（基于时间戳数值）
+//   Type_Float: 浮点数比较
+// 
+// 排序方向:
+//   'a' 表示升序，其他值表示降序
+func (c *LevelDBComparator) mycompare(types, orders, a, b string) int {
+	ret := 0
+	// 遍历所有比较类型
+	for i := 0; i < len(types); i++ {
+		switch string(types[i]) {
+		case utils.Type_String:
+			ret = strings.Compare(a, b)
+		case utils.Type_Int:
+		case utils.Type_Date:
+			// 将字符串转换为时间戳进行比较
+			ai, _ := strconv.ParseInt(a, 10, 64)
+			bi, _ := strconv.ParseInt(b, 10, 64)
+			if ai < bi {
+				ret = -1
+			} else if ai > bi {
+				ret = 1
+			}
+		case utils.Type_Float:
+			// 将字符串转换为浮点数进行比较
+			af, _ := strconv.ParseFloat(a, 64)
+			bf, _ := strconv.ParseFloat(b, 64)
+			if af < bf {
+				ret = -1
+			} else if af > bf {
+				ret = 1
+			}
+		}
+		// 根据排序方向调整比较结果
+		if ret != 0 {
+			if string(orders[i]) == "a" {
+				return ret
+			}
+			return -1 * ret
+		}
+	}
+	return ret
+}

utils/constant.go

@@ -0,0 +1,13 @@
+package utils
+
+const (
+	Prefix_Index_Data    = "indexes:data:"
+	Prefix_Index_Meta    = "indexes:meta:"
+	Separator_Key        = ":"
+	Separator_IndexField = "|"
+	Type_String          = "s"
+	Type_Int             = "i"
+	Type_Float           = "f"
+	Type_Bool            = "b"
+	Type_Date            = "d"
+)