fix(search): filter all special characters when searching

internal/repo/answer/answer_repo.go

@@ -422,7 +422,7 @@ func (ar *answerRepo) updateSearch(ctx context.Context, answerID string) (err er
 		ObjectID:    answerID,
 		Title:       question.Title,
 		Type:        constant.AnswerObjectType,
-		Content:     answer.ParsedText,
+		Content:     answer.OriginalText,
 		Answers:     0,
 		Status:      plugin.SearchContentStatus(answer.Status),
 		Tags:        tags,

internal/repo/question/question_repo.go

@@ -468,7 +468,7 @@ func (qr *questionRepo) updateSearch(ctx context.Context, questionID string) (er
 		ObjectID:    questionID,
 		Title:       question.Title,
 		Type:        constant.QuestionObjectType,
-		Content:     question.ParsedText,
+		Content:     question.OriginalText,
 		Answers:     int64(question.AnswerCount),
 		Status:      plugin.SearchContentStatus(question.Status),
 		Tags:        tags,

internal/schema/search_schema.go

@@ -2,7 +2,10 @@ package schema
 
 import (
 	"github.com/answerdev/answer/internal/base/constant"
+	"github.com/answerdev/answer/internal/base/validator"
 	"github.com/answerdev/answer/plugin"
+	"regexp"
+	"strings"
 )
 
 type SearchDTO struct {
@@ -15,6 +18,15 @@ type SearchDTO struct {
 	CaptchaCode string `json:"captcha_code"`
 }
 
+func (s *SearchDTO) Check() (errField []*validator.FormErrorField, err error) {
+	// Replace special characters.
+	// Special characters will cause the search abnormal, such as search for "#" will get nearly all the content that Markdown format.
+	s.Query = regexp.MustCompile(`[+#.<>\-_()*]`).ReplaceAllString(s.Query, " ")
+	s.Query = regexp.MustCompile(`\s+`).ReplaceAllString(s.Query, " ")
+	s.Query = strings.TrimSpace(s.Query)
+	return nil, nil
+}
+
 type SearchCondition struct {
 	// search target type: all/question/answer
 	TargetType string

internal/service/search_service.go

@@ -28,6 +28,12 @@ func (ss *SearchService) Search(ctx context.Context, dto *schema.SearchDTO) (res
 	if dto.Page < 1 {
 		dto.Page = 1
 	}
+	if len(dto.Query) == 0 {
+		return &schema.SearchResp{
+			Total:         0,
+			SearchResults: make([]*schema.SearchResult, 0),
+		}, nil
+	}
 
 	// search type
 	cond := ss.searchParser.ParseStructure(ctx, dto)