两张表在数组内 一对一 关联查询实现 50%

Author: j2go

README.md

@@ -19,6 +19,4 @@
 - [ ] 5.实现两张表在数组内 一对一 关联查询
 - [ ] 6.实现两张表在数组内 一对多 关联查询
 - [ ] 7.实现SQL的 column, order by, group by等功能。
-- [ ] 8.实现增、删、改
-
-
+- [ ] 8.实现增、删、改

db/db.go

@@ -11,7 +11,7 @@ import (
 
 var db *sqlx.DB
 
-const dataSourceName = "root:123456@tcp(localhost:3306)/apijson"
+const dataSourceName = "root:123456@tcp(localhost:3306)/sys"
 
 type TableMeta struct {
 	Name    string

db/sqlparser.go

@@ -8,9 +8,10 @@ import (
 	"strings"
 )
 
-type SQLParseObject struct {
+type SQLParser struct {
+	Key        string
 	LoadFunc   func(s string) interface{}
-	QueryFirst bool
+	RequestMap map[string]interface{}
 	Values     []interface{}
 
 	table    string
@@ -20,20 +21,43 @@ type SQLParseObject struct {
 	limit    int
 	page     int
 	withPage bool
+
+	children []SQLParser
 }
 
-func (o *SQLParseObject) From(key string, fieldMap map[string]interface{}) error {
-	if strings.HasSuffix(key, "[]") {
-		o.QueryFirst = false
-		return o.parseListQuery(fieldMap)
+func (o *SQLParser) GetData() (interface{}, error) {
+	if strings.HasSuffix(o.Key, "[]") {
+		if err := o.parseListQuery(); err != nil {
+			return nil, err
+		}
+		values, err := QueryAll(o.ToSQL(), o.Values...)
+		if err != nil {
+			return nil, err
+		}
+		if len(o.children) > 0 {
+			for _, v := range values {
+				for _, childParser := range o.children {
+					if data, err := childParser.GetData(); err != nil {
+						return nil, err
+					} else {
+						v[childParser.Key] = data
+					}
+				}
+			}
+		}
+		return values, nil
 	}
-	o.QueryFirst = true
-	return o.parseObject(key, fieldMap)
+	err := o.parseObject()
+	if err != nil {
+		return nil, err
+	}
+	sql := o.ToSQL()
+	logger.Debugf("解析 %s 执行SQL: %s %v", o.Key, sql, o.Values)
+	return QueryOne(sql, o.Values...), nil
 }
 
-func (o *SQLParseObject) parseObject(key string, fieldMap map[string]interface{}) error {
-	o.table = key
-	for field, value := range fieldMap {
+func (o *SQLParser) parseObject() error {
+	for field, value := range o.RequestMap {
 		if value == nil {
 			return fmt.Errorf("field value error, %s is nil", field)
 		}
@@ -62,7 +86,7 @@ func (o *SQLParseObject) parseObject(key string, fieldMap map[string]interface{}
 	return nil
 }
 
-func (o *SQLParseObject) parseRangeCondition(field string, value interface{}) {
+func (o *SQLParser) parseRangeCondition(field string, value interface{}) {
 	// 数组使用 IN 条件
 	if values, ok := value.([]interface{}); ok {
 		condition := field + " in ("
@@ -86,9 +110,9 @@ func (o *SQLParseObject) parseRangeCondition(field string, value interface{}) {
 	}
 }
 
-func (o *SQLParseObject) parseListQuery(fieldMap map[string]interface{}) error {
-
-	for field, value := range fieldMap {
+func (o *SQLParser) parseListQuery() error {
+	o.table = o.Key[0 : len(o.Key)-2]
+	for field, value := range o.RequestMap {
 		if value == nil {
 			return fmt.Errorf("field value error, %s is nil", field)
 		}
@@ -101,7 +125,7 @@ func (o *SQLParseObject) parseListQuery(fieldMap map[string]interface{}) error {
 			logger.Debugf("parseListQuery table:%s, size: %d", o.table, o.limit)
 		default:
 			if _, ok := AllTable[field]; ok {
-				if err := o.parseObject(field, value.(map[string]interface{})); err != nil {
+				if err := o.parseObject(); err != nil {
 					return err
 				}
 			} else {
@@ -110,13 +134,13 @@ func (o *SQLParseObject) parseListQuery(fieldMap map[string]interface{}) error {
 		}
 	}
 	if len(o.table) == 0 {
-		return fmt.Errorf("请求列表数据处理失败，未发现可用表名 %v", fieldMap)
+		return fmt.Errorf("请求列表数据处理失败，未发现可用表名 %v", o.RequestMap)
 	}
 	o.withPage = o.page > 0 && o.limit > 0
 	return nil
 }
 
-func (o *SQLParseObject) ToSQL() string {
+func (o *SQLParser) ToSQL() string {
 	var buf bytes.Buffer
 	buf.WriteString("SELECT ")
 	if o.columns == nil {
@@ -134,7 +158,7 @@ func (o *SQLParseObject) ToSQL() string {
 		buf.WriteString(" ORDER BY ")
 		buf.WriteString(o.order)
 	}
-	if o.QueryFirst {
+	if o.Key == o.table {
 		buf.WriteString(" LIMIT 1")
 	} else if o.withPage {
 		buf.WriteString(" LIMIT ")

design.md

@@ -82,4 +82,35 @@ if rows.Next() {
 error: 39:1: expected '}', found 0 (and 10 more errors)
 ```
 
-这个报错也太简略了，翻了一下源码，感觉短时间里搞不定，还是自己写一个吧，挖个坑之后填，先把 0.0.1 的功能完成
+这个报错也太简略了，翻了一下源码，感觉短时间里搞不定，还是自己写一个吧，挖个坑之后填，先把 0.0.1 的功能完成
+
+# 一些问题
+
+在使用 Java 版的时候发现一个反直觉的点
+```json
+{
+    "User":{
+        "id": 93793
+    },
+    "[]": {
+        "page": 0,
+        "count": 3,
+        "Moment": {
+            "userId@": "User/id",
+            "@column": "id,content,userId"
+        },
+        "list[]": {
+            "count": 3,
+            "Comment": {
+                "momentId@": "[]/Moment/id"
+            },
+            "User": {
+                "id@": "/Comment/userId"
+            }
+        }
+    }
+}
+```
+上面  `"userId@": "User/id",` 查的是绝对路径，
+下面 `"id@": "/Comment/userId"` 查的却是相对路径，
+就 Linux 的使用习惯来说 `/` 在前表示的是绝对路径

handler/getHandler.go

@@ -70,13 +70,13 @@ func (c *SQLParseContext) getResponse() map[string]interface{} {
 			}
 		}
 	}
+	c.resp["code"] = http.StatusOK
 	c.resp["time"] = fmt.Sprintf("%dms|%v", (time.Now().Nanosecond()-startTime)/1000000, c.time)
 	return c.resp
 }
 
 func (c *SQLParseContext) parseSQLAndGetResponse(key string) {
 	startTime := time.Now().UnixNano()
-
 	c.waitKeys[key] = true
 	logger.Debugf("开始解析 %s", key)
 	if c.req[key] == nil {
@@ -86,34 +86,20 @@ func (c *SQLParseContext) parseSQLAndGetResponse(key string) {
 	if fieldMap, ok := c.req[key].(map[string]interface{}); !ok {
 		c.End(http.StatusBadRequest, "值类型不对，只支持 Object 类型")
 	} else {
-		parseObj := db.SQLParseObject{LoadFunc: c.queryResp}
-		if c.end {
-			return
-		}
-		if err := parseObj.From(key, fieldMap); err != nil {
-			c.End(http.StatusBadRequest, err.Error())
-			return
+		obj := &db.SQLParser{Key: key, LoadFunc: c.queryResponse, RequestMap: fieldMap}
+		value, err := obj.GetData()
+		if err != nil {
+			c.End(http.StatusInternalServerError, err.Error())
 		} else {
-			sql := parseObj.ToSQL()
-			logger.Debugf("解析 %s 执行SQL: %s %v", key, sql, parseObj.Values)
-			if parseObj.QueryFirst {
-				c.resp[key], err = db.QueryOne(sql, parseObj.Values...)
-			} else {
-				c.resp[key], err = db.QueryAll(sql, parseObj.Values...)
-			}
-			if err != nil {
-				c.End(http.StatusInternalServerError, err.Error())
-			} else {
-				c.resp["code"] = http.StatusOK
-			}
+			c.resp[key] = value
 		}
 	}
 	c.waitKeys[key] = false
 	c.time[key] = time.Now().UnixNano() - startTime
 }
 
 // 查询已知结果
-func (c *SQLParseContext) queryResp(queryString string) interface{} {
+func (c *SQLParseContext) queryResponse(queryString string) interface{} {
 	var paths []string
 	qs := strings.TrimSpace(queryString)
 	if strings.HasPrefix(qs, "/") {