Merge pull request go-gorm#167 from go-gorm/dev

add method GetFieldByName
sujunbo · Oct 26, 2021 · ea149b7 · ea149b7
2 parents 2fce38b + ad3d06a
commit ea149b7
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Showing 4 changed files with 46 additions and 10 deletions.
diff --git a/do.go b/do.go
@@ -171,7 +171,8 @@ func (d *DO) Select(columns ...field.Expr) Dao {
 	if len(columns) == 0 {
 		return d.getInstance(d.db.Clauses(clause.Select{}))
 	}
-	return d.getInstance(d.db.Select(buildExpr(d.db.Statement, columns...)))
+	query, args := buildExpr(d.db.Statement, columns...)
+	return d.getInstance(d.db.Select(query, args...))
 }
 
 func (d *DO) Where(conds ...Condition) Dao {
@@ -580,12 +581,17 @@ func buildColumn(stmt *gorm.Statement, cols []field.Expr, opts ...field.BuildOpt
 	return results
 }
 
-func buildExpr(stmt *gorm.Statement, exprs ...field.Expr) []string {
-	results := make([]string, len(exprs))
-	for i, e := range exprs {
-		results[i] = e.Build(stmt).String()
+func buildExpr(stmt *gorm.Statement, exprs ...field.Expr) (query string, args []interface{}) {
+	for _, e := range exprs {
+		sql, vars := e.BuildWithArgs(stmt)
+		if query == "" {
+			query = sql.String()
+		} else {
+			query += "," + sql.String()
+		}
+		args = append(args, vars...)
 	}
-	return results
+	return query, args
 }
 
 func toExpression(exprs ...field.Expr) []clause.Expression {

diff --git a/field/expr.go b/field/expr.go
@@ -21,6 +21,7 @@ type Expr interface {
 	ColumnName() sql
 	BuildColumn(*gorm.Statement, ...BuildOpt) sql
 	Build(*gorm.Statement) sql
+	BuildWithArgs(*gorm.Statement) (query sql, args []interface{})
 	RawExpr() expression
 
 	// implement Condition
@@ -103,6 +104,15 @@ func (e expr) Build(stmt *gorm.Statement) sql {
 	return sql(newStmt.SQL.String())
 }
 
+func (e expr) BuildWithArgs(stmt *gorm.Statement) (sql, []interface{}) {
+	if e.e == nil {
+		return sql(e.BuildColumn(stmt, WithAll)), nil
+	}
+	newStmt := &gorm.Statement{DB: stmt.DB, Table: stmt.Table, Schema: stmt.Schema}
+	e.e.Build(newStmt)
+	return sql(newStmt.SQL.String()), newStmt.Vars
+}
+
 func (e expr) RawExpr() expression {
 	if e.e == nil {
 		return e.col

diff --git a/field/external_test.go b/field/external_test.go
@@ -307,6 +307,11 @@ func TestExpr_Build(t *testing.T) {
 			ExpectedVars: []interface{}{time.Duration(24 * time.Hour).Microseconds()},
 			Result:       "DATE_SUB(`creatAt`, INTERVAL ? MICROSECOND)",
 		},
+		{
+			Expr:         field.NewTime("", "updateAt").DateFormat("%W %M %Y"),
+			ExpectedVars: []interface{}{"%W %M %Y"},
+			Result:       "DATE_FORMAT(`updateAt`,?)",
+		},
 		// ======================== bool ========================
 		{
 			Expr:   field.NewBool("", "male").Not(),

diff --git a/internal/template/struct.go b/internal/template/struct.go
@@ -7,7 +7,7 @@ const (
 		` + members + `
 	}
 	
-	` + cloneMethod + relationship + defineMethodStruct
+	` + getFieldMethod + cloneMethod + relationship + defineMethodStruct
 
 	BaseStructWithContext = createMethod + `
 	type {{.NewStructName}} struct {
@@ -17,9 +17,11 @@ const (
 	
 	func ({{.S}} *{{.NewStructName}}) WithContext(ctx context.Context) *{{.NewStructName}}Do { return {{.S}}.{{.NewStructName}}Do.WithContext(ctx)}
 
-	func ({{.S}} {{.NewStructName}}) TableName() string { return {{.S}}.{{.NewStructName}}Do.TableName()}
+	func ({{.S}} {{.NewStructName}}) TableName() string { return {{.S}}.{{.NewStructName}}Do.TableName()} 
+
+	
 	
-	` + cloneMethod + relationship + defineMethodStruct
+	` + getFieldMethod + cloneMethod + relationship + defineMethodStruct
 )
 
 const (
@@ -43,7 +45,12 @@ const (
 			}
 		{{end}}
 		{{end}}
-	
+
+		{{range .Members -}}
+		{{if not .IsRelation -}}
+			_{{$.NewStructName}}.fieldMap["{{.ColumnName}}"] = _{{$.NewStructName}}.{{.Name}}
+		{{end -}}
+		{{end}}
 		return _{{.NewStructName}}
 	}
 	`
@@ -57,12 +64,20 @@ const (
 		{{.Relation.Name}} {{$.NewStructName}}{{.Relation.RelationshipName}}{{.Relation.Name}}
 	{{end}}
 	{{end}}
+
+	fieldMap  map[string]field.Expr
 `
 	cloneMethod = `
 func ({{.S}} {{.NewStructName}}) clone(db *gorm.DB) {{.NewStructName}} {
 	{{.S}}.{{.NewStructName}}Do.ReplaceDB(db)
 	return {{.S}}
 }
+`
+	getFieldMethod = `
+func ({{.S}} *{{.NewStructName}}) GetFieldByName(fieldName string) (field.Expr, bool) {
+	field, ok := {{.S}}.fieldMap[fieldName]
+	return field, ok
+}
 `
 	relationship = `{{range .Members}}{{if .IsRelation}}` +
 		`{{- $relation := .Relation }}{{- $relationship := $relation.RelationshipName}}` +