feat: build delete support limit (#148)

* feat: build delete support limit

* feat: build delete support limit

* feat: build delete support limit

* feat: build delete support limit

builder/builder.go

@@ -21,7 +21,7 @@ var (
 	errHavingUnsupportedOperator = errors.New(`[builder] "_having" contains unsupported operator`)
 	errLockModeValueType         = errors.New(`[builder] the value of "_lockMode" must be of string type`)
 	errNotAllowedLockMode        = errors.New(`[builder] the value of "_lockMode" is not allowed`)
-	errUpdateLimitType           = errors.New(`[builder] the value of "_limit" in update query must be one of int,uint,int64,uint64`)
+	errLimitType                 = errors.New(`[builder] the value of "_limit" must be one of int,uint,int64,uint64`)
 
 	errWhereInterfaceSliceType = `[builder] the value of "xxx %s" must be of []interface{} type`
 	errEmptySliceCondition     = `[builder] the value of "%s" must contain at least one element`
@@ -170,8 +170,7 @@ func resolveHaving(having interface{}) (map[string]interface{}, error) {
 	return copiedMap, nil
 }
 
-// BuildUpdate work as its name says
-func BuildUpdate(table string, where map[string]interface{}, update map[string]interface{}) (string, []interface{}, error) {
+func getLimit(where map[string]interface{}) (uint, error) {
 	var limit uint
 	if v, ok := where["_limit"]; ok {
 		switch val := v.(type) {
@@ -184,9 +183,18 @@ func BuildUpdate(table string, where map[string]interface{}, update map[string]i
 		case uint64:
 			limit = uint(val)
 		default:
-			return "", nil, errUpdateLimitType
+			return 0, errLimitType
 		}
 	}
+	return limit, nil
+}
+
+// BuildUpdate work as its name says
+func BuildUpdate(table string, where map[string]interface{}, update map[string]interface{}) (string, []interface{}, error) {
+	limit, err := getLimit(where)
+	if err != nil {
+		return "", nil, err
+	}
 	conditions, err := getWhereConditions(where, defaultIgnoreKeys)
 	if nil != err {
 		return "", nil, err
@@ -196,11 +204,15 @@ func BuildUpdate(table string, where map[string]interface{}, update map[string]i
 
 // BuildDelete work as its name says
 func BuildDelete(table string, where map[string]interface{}) (string, []interface{}, error) {
+	limit, err := getLimit(where)
+	if err != nil {
+		return "", nil, err
+	}
 	conditions, err := getWhereConditions(where, defaultIgnoreKeys)
 	if nil != err {
 		return "", nil, err
 	}
-	return buildDelete(table, conditions...)
+	return buildDelete(table, limit, conditions...)
 }
 
 // BuildInsert work as its name says

builder/builder_test.go

@@ -388,11 +388,12 @@ func Test_BuildDelete(t *testing.T) {
 					"age >=":   21,
 					"sex in":   []interface{}{"male", "female"},
 					"hobby in": []interface{}{"soccer", "basketball", "tenis"},
+					"_limit":   10,
 				},
 			},
 			out: outStruct{
-				cond: "DELETE FROM tb WHERE (hobby IN (?,?,?) AND sex IN (?,?) AND age>=?)",
-				vals: []interface{}{"soccer", "basketball", "tenis", "male", "female", 21},
+				cond: "DELETE FROM tb WHERE (hobby IN (?,?,?) AND sex IN (?,?) AND age>=?) LIMIT ?",
+				vals: []interface{}{"soccer", "basketball", "tenis", "male", "female", 21, 10},
 				err:  nil,
 			},
 		},
@@ -486,7 +487,7 @@ func Test_BuildUpdate(t *testing.T) {
 			out: outStruct{
 				cond: "",
 				vals: nil,
-				err:  errUpdateLimitType,
+				err:  errLimitType,
 			},
 		},
 	}

builder/dao.go

@@ -439,14 +439,18 @@ func buildUpdate(table string, update map[string]interface{}, limit uint, condit
 	return cond, vals, nil
 }
 
-func buildDelete(table string, conditions ...Comparable) (string, []interface{}, error) {
+func buildDelete(table string, limit uint, conditions ...Comparable) (string, []interface{}, error) {
 	whereString, vals := whereConnector("AND", conditions...)
 	if "" == whereString {
 		return fmt.Sprintf("DELETE FROM %s", table), nil, nil
 	}
 	format := "DELETE FROM %s WHERE %s"
 
 	cond := fmt.Sprintf(format, quoteField(table), whereString)
+	if limit > 0 {
+		cond += " LIMIT ?"
+		vals = append(vals, int(limit))
+	}
 	return cond, vals, nil
 }
 

builder/dao_test.go

@@ -363,13 +363,15 @@ func TestBuildUpdate(t *testing.T) {
 func TestBuildDelete(t *testing.T) {
 	var data = []struct {
 		table   string
+		limit   uint
 		where   []Comparable
 		outStr  string
 		outVals []interface{}
 		outErr  error
 	}{
 		{
 			table: "tb",
+			limit: 5,
 			where: []Comparable{
 				Eq(map[string]interface{}{
 					"foo":        1,
@@ -378,14 +380,14 @@ func TestBuildDelete(t *testing.T) {
 					"gmt_create": Raw("gmt_modified"),
 				}),
 			},
-			outStr:  "DELETE FROM tb WHERE (bar=? AND baz=? AND foo=? AND gmt_create=gmt_modified)",
-			outVals: []interface{}{2, "tt", 1},
+			outStr:  "DELETE FROM tb WHERE (bar=? AND baz=? AND foo=? AND gmt_create=gmt_modified) LIMIT ?",
+			outVals: []interface{}{2, "tt", 1, 5},
 			outErr:  nil,
 		},
 	}
 	ass := assert.New(t)
 	for _, tc := range data {
-		actualStr, actualVals, err := buildDelete(tc.table, tc.where...)
+		actualStr, actualVals, err := buildDelete(tc.table, tc.limit, tc.where...)
 		ass.Equal(tc.outErr, err)
 		ass.Equal(tc.outStr, actualStr)
 		ass.Equal(tc.outVals, actualVals)