feat: 태그 검색 기능 추가

internal/http/handler/postinghandler.go

@@ -1,16 +1,20 @@
 package handler
 
 import (
+	"fmt"
 	"net/http"
+	"strings"
 	"time"
 
+	"entgo.io/ent/dialect/sql"
 	"github.com/gin-gonic/gin"
 	"github.com/techbloghub/server/ent"
+	"github.com/techbloghub/server/ent/company"
 	"github.com/techbloghub/server/ent/posting"
 	"github.com/techbloghub/server/internal/common"
 )
 
-type TitleSearchResponse struct {
+type PostingSearchResponse struct {
 	ID            int       `json:"posting_id"`
 	Title         string    `json:"title"`
 	Url           string    `json:"url"`
@@ -23,73 +27,111 @@ type TitleSearchResponse struct {
 }
 
 type PostingSearchResponses struct {
-	Count       int                   `json:"count"`
-	Postings    []TitleSearchResponse `json:"postings"`
-	HasNextPage bool                  `json:"has_next_page"`
+	Count       int                     `json:"count"`
+	Postings    []PostingSearchResponse `json:"postings"`
+	HasNextPage bool                    `json:"has_next_page"`
 }
 
 func GetPostings(client *ent.Client) gin.HandlerFunc {
 	return func(c *gin.Context) {
 		titleSearchParam := c.DefaultQuery("title", "")
+		tagsSearchParam := c.DefaultQuery("tags", "")
 		paging := common.GenerateTechPaging(c.Query("cursor"), c.Query("size"))
 
-		totalCount, err := countTotalPostings(client, titleSearchParam, c)
+		postings, err := fetchPostings(client, titleSearchParam, tagsSearchParam, paging, c)
 		if err != nil {
 			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
 			return
 		}
 
-		postings, err := fetchPostings(client, titleSearchParam, paging, c)
+		totalCount, err := countPostings(client, titleSearchParam, tagsSearchParam, c)
 		if err != nil {
 			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
 			return
 		}
 
 		c.JSON(http.StatusOK, PostingSearchResponses{
 			Count:       totalCount,
-			Postings:    convertToTitleSearchResponse(postings),
+			Postings:    toPostingSearchResponses(postings),
 			HasNextPage: paging.HasNextPage(totalCount),
 		})
 	}
 }
 
-func fetchPostings(client *ent.Client, title string, paging common.TechbloghubPaging, c *gin.Context) ([]*ent.Posting, error) {
-	query := client.Posting.Query().WithCompany()
+func applySearchFilters(query *ent.PostingQuery, title, tags string) *ent.PostingQuery {
 	if title != "" {
 		query = query.Where(posting.TitleContainsFold(title))
 	}
-	if paging.Cursor > 0 {
-		query = query.Where(posting.IDLT(paging.Cursor))
+	// 태그 조회 케이스 -> postgresql ARRAY 검색 형식에 맞춰야함
+	// tags: [react,java]
+	// query : where tags @> ARRAY['react','java']
+	if tags != "" {
+		arr := strings.Split(tags, ",")
+		arrayQuery := "ARRAY" + fmt.Sprintf("['%s']", strings.Join(arr, ","))
+
+		query = query.Where(func(s *sql.Selector) {
+			s.Where(sql.ExprP(fmt.Sprintf("%s @> %s", s.C("tags"), arrayQuery)))
+		})
 	}
 
-	return query.Order(
-		ent.Desc(posting.FieldPublishedAt),
-		ent.Desc(posting.FieldID),
-	).Limit(paging.Size).All(c)
+	return query
 }
 
-func countTotalPostings(client *ent.Client, title string, c *gin.Context) (int, error) {
+func fetchPostings(client *ent.Client, title, tags string, paging common.TechbloghubPaging, c *gin.Context) ([]*ent.Posting, error) {
 	query := client.Posting.Query()
-	if title != "" {
-		query = query.Where(posting.TitleContainsFold(title))
+	query = applySearchFilters(query, title, tags)
+
+	if paging.Cursor > common.CURSOR_DEFAULT {
+		query = query.Where(posting.IDLT(paging.Cursor))
 	}
+
+	return query.Where(posting.HasCompany()).
+		WithCompany(func(q *ent.CompanyQuery) {
+			q.Select(
+				company.FieldLogoURL,
+				company.FieldName,
+			)
+		}).
+		Order(
+			ent.Desc(posting.FieldPublishedAt),
+			ent.Desc(posting.FieldID),
+		).
+		Limit(paging.Size).
+		All(c.Request.Context())
+}
+
+func countPostings(client *ent.Client, title, tags string, c *gin.Context) (int, error) {
+	query := client.Posting.Query()
+	query = applySearchFilters(query, title, tags)
 	return query.Count(c)
 }
 
-func convertToTitleSearchResponse(postings []*ent.Posting) []TitleSearchResponse {
-	responses := make([]TitleSearchResponse, len(postings))
-	for i, posting := range postings {
-		responses[i] = TitleSearchResponse{
+// 대체 왜 못갖고오냐!!!!
+func getCompanyInfo(posting *ent.Posting) (string, string) {
+	if posting.Edges.Company != nil {
+		return posting.Edges.Company.Name, posting.Edges.Company.LogoURL.String()
+	}
+	return "Unknown", ""
+}
+
+func toPostingSearchResponses(postings []*ent.Posting) []PostingSearchResponse {
+	responses := make([]PostingSearchResponse, len(postings))
+
+	for _, posting := range postings {
+		companyName, logoURL := getCompanyInfo(posting)
+
+		responses = append(responses, PostingSearchResponse{
 			ID:            posting.ID,
 			Title:         posting.Title,
 			Url:           posting.URL.String(),
-			Company:       posting.Edges.Company.Name,
-			Logo:          posting.Edges.Company.LogoURL.String(),
+			Company:       companyName,
+			Logo:          logoURL,
 			Tags:          posting.Tags.ToStringSlice(),
 			CreateTime:    posting.CreateTime,
 			UpdateTime:    posting.UpdateTime,
 			PublishedTime: posting.PublishedAt,
-		}
+		})
 	}
+
 	return responses
 }