fix:#34 added transaction for main fetch datasource

backend/service/addCalDavRoutes.go

@@ -60,18 +60,17 @@ func addFeedRoutes(app *pocketbase.PocketBase) {
 				if err != nil {
 					return c.JSON(http.StatusInternalServerError, "Failed to get feed")
 				}
-				var responseWriter = c.Response().Writer
-				responseWriter.Header().Set("Content-type", "text/calendar")
-				responseWriter.Header().Set("charset", "utf-8")
-				responseWriter.Header().Set("Content-Disposition", "inline")
-				responseWriter.Header().Set("filename", "calendar.ics")
 
-				responseWriter.WriteHeader(http.StatusOK)
+				c.Response().Header().Set("Content-type", "text/calendar")
-				_, err = responseWriter.Write([]byte(result))
+				c.Response().Header().Set("charset", "utf-8")
+				c.Response().Header().Set("Content-Disposition", "inline")
+				c.Response().Header().Set("filename", "calendar.ics")
+
+				_, err = c.Response().Write([]byte(result))
+
 				if err != nil {
-					return c.JSON(http.StatusInternalServerError, "Failed to write feed")
+					return err
 				}
-				c.Response().Writer = responseWriter
 				return nil
 			},
 			Middlewares: []echo.MiddlewareFunc{

backend/service/db/dbEvents.go

@@ -18,6 +18,7 @@ package db
 
 import (
 	"fmt"
+	"github.com/pocketbase/pocketbase/daos"
 	"github.com/pocketbase/pocketbase/tools/types"
 	"htwkalender/model"
 	"log/slog"
@@ -34,7 +35,7 @@ func SaveSeminarGroupEvents(seminarGroup model.SeminarGroup, app *pocketbase.Poc
 	// check if event is already in database and add to toBeSavedEvents if not
 	for _, event := range seminarGroup.Events {
 		event = event.SetCourse(seminarGroup.Course)
-		existsInDatabase, err := findEventByDayWeekStartEndNameCourse(event, seminarGroup.Course, app)
+		existsInDatabase, err := findEventByDayWeekStartEndNameCourse(event, seminarGroup.Course, app.Dao())
 		alreadyAddedToSave := toBeSavedEvents.Contains(event)
 
 		if err != nil {
@@ -61,13 +62,44 @@ func SaveSeminarGroupEvents(seminarGroup model.SeminarGroup, app *pocketbase.Poc
 	return savedRecords, nil
 }
 
+func SaveEventsTxDao(events []model.Event, txDao *daos.Dao) ([]model.Event, error) {
+	var toBeSavedEvents model.Events
+	var savedRecords model.Events
+
+	// check if event is already in database and add to toBeSavedEvents if not
+	for _, event := range events {
+		existsInDatabase, err := findEventByDayWeekStartEndNameCourse(event, event.Course, txDao)
+		alreadyAddedToSave := toBeSavedEvents.Contains(event)
+
+		if err != nil {
+			return nil, err
+		}
+
+		if !existsInDatabase && !alreadyAddedToSave {
+			toBeSavedEvents = append(toBeSavedEvents, event)
+		}
+	}
+	// create record for each event that's not already in the database
+	for _, event := range toBeSavedEvents {
+		event.MarkAsNew()
+		// auto mapping for event fields to record fields
+		err := txDao.Save(&event)
+		if err != nil {
+			return nil, err
+		} else {
+			savedRecords = append(savedRecords, event)
+		}
+	}
+	return savedRecords, nil
+}
+
 func SaveEvents(events []model.Event, app *pocketbase.PocketBase) ([]model.Event, error) {
 	var toBeSavedEvents model.Events
 	var savedRecords model.Events
 
 	// check if event is already in database and add to toBeSavedEvents if not
 	for _, event := range events {
-		existsInDatabase, err := findEventByDayWeekStartEndNameCourse(event, event.Course, app)
+		existsInDatabase, err := findEventByDayWeekStartEndNameCourse(event, event.Course, app.Dao())
 		alreadyAddedToSave := toBeSavedEvents.Contains(event)
 
 		if err != nil {
@@ -94,11 +126,11 @@ func SaveEvents(events []model.Event, app *pocketbase.PocketBase) ([]model.Event
 }
 
 // check if event is already in database and return true if it is and false if it's not
-func findEventByDayWeekStartEndNameCourse(event model.Event, course string, app *pocketbase.PocketBase) (bool, error) {
+func findEventByDayWeekStartEndNameCourse(event model.Event, course string, dao *daos.Dao) (bool, error) {
 
 	var dbEvent model.Event
 
-	err := app.Dao().DB().Select("*").From("events").
+	err := dao.DB().Select("*").From("events").
 		Where(dbx.NewExp(
 			"Day = {:day} AND "+
 				"Week = {:week} AND "+
@@ -239,15 +271,6 @@ func DeleteAllEventsByCourse(app *pocketbase.PocketBase, course string, semester
 	return nil
 }
 
-func DeleteAllEventsBySemesterWithoutCourse(app *pocketbase.PocketBase, course string, semester string) error {
-	_, err := app.Dao().DB().Delete("events", dbx.NewExp("course != {:course} AND semester = {:semester}", dbx.Params{"course": course, "semester": semester})).Execute()
-
-	if err != nil {
-		return err
-	}
-	return nil
-}
-
 func DeleteAllEvents(app *pocketbase.PocketBase) error {
 
 	_, err := app.Dao().DB().Delete("events", dbx.NewExp("1=1")).Execute()

backend/service/fetch/v2/fetcher.go

@@ -17,9 +17,12 @@
 package v2
 
 import (
+	"database/sql"
 	"fmt"
 	"github.com/google/uuid"
+	"github.com/pocketbase/dbx"
 	"github.com/pocketbase/pocketbase"
+	"github.com/pocketbase/pocketbase/daos"
 	"golang.org/x/net/html"
 	"htwkalender/model"
 	"htwkalender/service/db"
@@ -89,21 +92,50 @@ func fetchAndSaveAllEventsForSemester(
 	var savedRecords []model.Event
 	url := stubUrl[0] + semester + stubUrl[1]
 	events, err := parseEventForOneSemester(url)
+
 	if err != nil {
 		return nil, fmt.Errorf("failed to parse events for "+semester+": %w", err)
 	}
-	err = db.DeleteAllEventsBySemesterWithoutCourse(app, "Sport", semester)
+
-	if err != nil {
+	err = updateDatabase(app, events, "Sport", semester)
-		return nil, fmt.Errorf("failed to delete all events for "+semester+": %w", err)
+
-	}
-	savedEvents, dbError := db.SaveEvents(events, app)
-	if dbError != nil {
-		return nil, fmt.Errorf("failed to save events for "+semester+": %w", dbError)
-	}
-	savedRecords = append(savedRecords, savedEvents...)
 	return savedRecords, err
 }
 
+func updateDatabase(app *pocketbase.PocketBase, eventsToBeAdded []model.Event, course string, semester string) error {
+
+	var addedEvents []model.Event
+	var err error
+
+	// to in transaction the events will be added and deleted
+	err = app.Dao().RunInTransaction(func(txDao *daos.Dao) error {
+		var execute sql.Result
+		execute, err = txDao.DB().Delete("events",
+			dbx.NewExp("course != {:course} AND semester = {:semester}",
+				dbx.Params{"course": course, "semester": semester})).Execute()
+		if err != nil {
+			return err
+		}
+		var rows int64
+		rows, err = execute.RowsAffected()
+		slog.Info("Deleted events: ", "events", rows)
+
+		addedEvents, err = db.SaveEventsTxDao(eventsToBeAdded, txDao)
+		if err != nil {
+			return err
+		}
+
+		return nil
+	})
+	if err != nil {
+		return err
+	}
+
+	slog.Info("Added events: ", "events", len(addedEvents))
+
+	return nil
+}
+
 func parseEventForOneSemester(url string) ([]model.Event, error) {
 	// Fetch Webpage from URL
 	webpage, err := fetch.GetHTML(url)

docker-compose.yml

@@ -14,8 +14,6 @@
 #You should have received a copy of the GNU Affero General Public License
 #along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-version: "3.9"
-
 services:
   htwkalender-backend:
     build: