feat: add similar papers api

Signed-off-by: Rajiv Harlalka <[email protected]>

backend/handlers.go

@@ -357,6 +357,46 @@ func HandleProfile(w http.ResponseWriter, r *http.Request) {
 	sendResponse(w, http.StatusOK, map[string]string{"username": approverUsername})
 }
 
+func HandleFetchSimilarPapers(w http.ResponseWriter, r *http.Request) {
+	queryParams := r.URL.Query()
+	db := db.GetDB()
+
+	var parsedParams models.QuestionPaper
+	// parse Query Params
+	if !queryParams.Has("course_code") {
+		sendErrorResponse(w, http.StatusBadRequest, "query parameter course_code is mandatory", nil)
+		config.Get().Logger.Errorf("HandleSimilarPapers: query param 'course_code' not received")
+		return
+	}
+	parsedParams.CourseCode = queryParams.Get("course_code")
+	if queryParams.Has("year") {
+		year, err := strconv.Atoi(queryParams.Get("year"))
+		if err != nil {
+			sendErrorResponse(w, http.StatusBadRequest, "query parameter year has to be integer", nil)
+			config.Get().Logger.Errorf("HandleSimilarPapers: query param 'year' received a non-int value")
+			return
+		}
+		parsedParams.Year = &year
+	}
+
+	if queryParams.Has("semester") {
+		parsedParams.Semester = queryParams.Get("semester")
+	}
+
+	if queryParams.Has("exam") {
+		parsedParams.Exam = queryParams.Get("exam")
+	}
+	fmt.Print(parsedParams)
+	questionPapers, err := db.GetQuestionPaperWithExactMatch(&parsedParams)
+	if err != nil {
+		sendErrorResponse(w, http.StatusInternalServerError, "could not fetch question papers, try again later", nil)
+		config.Get().Logger.Errorf("HandleFetchSimilarPapers: Error fetching papers from db: %+v", err.Error())
+		return
+	}
+
+	sendResponse(w, http.StatusOK, questionPapers)
+}
+
 func HandleDeletePaper(w http.ResponseWriter, r *http.Request) {
 	approverUsername := r.Context().Value(CLAIMS_KEY).(*Claims).Username
 	db := db.GetDB()

backend/main.go

@@ -28,6 +28,7 @@ func main() {
 	http.Handle("POST /approve", JWTMiddleware(http.HandlerFunc(HandleApprovePaper)))
 	http.Handle("POST /delete", JWTMiddleware(http.HandlerFunc(HandleDeletePaper)))
 	http.Handle("GET /profile", JWTMiddleware(http.HandlerFunc(HandleProfile)))
+	http.Handle("GET /similar", JWTMiddleware(http.HandlerFunc(HandleFetchSimilarPapers)))
 
 	logger := config.Get().Logger
 	c := cors.New(cors.Options{

backend/pkg/db/query.go

@@ -71,3 +71,45 @@ func (db *db) MarkPaperAsSoftDeletedAndUnApprove(qpID int, approvedBy string) er
 	}
 	return nil
 }
+
+func (db *db) GetQuestionPaperWithExactMatch(paper *models.QuestionPaper) ([]models.QuestionPaper, error) {
+	query := "SELECT course_code,course_name,year,exam,filelink,id,from_library,semester from iqps where course_code = @course_code"
+	params := pgx.NamedArgs{
+		"course_code": paper.CourseCode,
+	}
+
+	if paper.Exam != "" {
+		query += " and exam = @exam"
+		params["exam"] = paper.Exam
+	}
+
+	if paper.Year != nil {
+		query += " and year = @year"
+		params["year"] = paper.Year
+	}
+
+	if paper.Semester != "" {
+		query += " and semester = @semester"
+		params["semester"] = paper.Semester
+	}
+	rows, err := db.Db.Query(context.Background(), query, params)
+	if err != nil {
+		config.Get().Logger.Errorf("GetQuestionPaperWithExactMatch: Could not fetch all question papers, error: %+v", err.Error())
+		return nil, errors.New("unable to fetch question paper, try again later")
+	}
+	defer rows.Close()
+
+	var qps []models.QuestionPaper = make([]models.QuestionPaper, 0)
+	for rows.Next() {
+		qp := models.QuestionPaper{}
+		err := rows.Scan(&qp.CourseCode, &qp.CourseName, &qp.Year, &qp.Exam, &qp.FileLink, &qp.ID, &qp.FromLibrary, &qp.Semester)
+		if err != nil {
+			config.Get().Logger.Errorf("FetchAllQuestionpapers: Error Scanning Paper in Struct, error: %+v", err.Error())
+			return nil, errors.New("unable to fetch question paper, try again later")
+		}
+		qp.FileLink = fmt.Sprintf("%s/%s", config.Get().StaticFilesUrl, qp.FileLink)
+		qps = append(qps, qp)
+	}
+
+	return qps, nil
+}

backend/pkg/models/model.go

@@ -8,7 +8,7 @@ type QuestionPaper struct {
 	ID              int              `json:"id"`
 	CourseCode      string           `json:"course_code"`
 	CourseName      string           `json:"course_name"`
-	Year            int              `json:"year"`
+	Year            *int             `json:"year"`
 	Exam            string           `json:"exam"`
 	FileLink        string           `json:"filelink"`
 	FromLibrary     bool             `json:"from_library"`