Refactor deletion and addition of cloud calendar events

Author: goyalmunish

internal/model/reminder_data.go

@@ -36,6 +36,7 @@ type ReminderData struct {
 
 // SyncCalendar syncs pending notes to Cloud Calendar.
 func (rd *ReminderData) SyncCalendar(calOptions *calendar.Options) error {
+	lookAheadYears := 5
 	if !EnableCalendar {
 		logger.Warn("Google Calendar is disabled.")
 		return nil
@@ -48,15 +49,13 @@ func (rd *ReminderData) SyncCalendar(calOptions *calendar.Options) error {
 		return fmt.Errorf("Unable to retrieve Calendar client: %w", err)
 	}
 
-	// Get list of all upcoming events
+	// Get list of all upcoming events, and display them
 	logger.Info("Fetch the list of all upcoming Calendar Events with each type of recurring event as single unit.")
-	existingEvents, eventDetails, timeZone, err := calendar.FetchUpcomingEventsAndDetails(srv, 5, "")
+	existingEvents, eventDetails, timeZone, err := calendar.FetchUpcomingEventsAndDetails(srv, 0, lookAheadYears, "")
 	if err != nil {
 		return err
 	}
-
 	fmt.Println(eventDetails)
-
 	// Iterating through the Cloud Calendar Events
 	fmt.Printf("Listing upcoming calendar events (%v):\n", len(existingEvents))
 	fmt.Println("Note: It may take some time for Google Calendar read API to pick up the recently added events, or Calendar trash https://calendar.google.com/calendar/u/0/r/trash can also cause issues.")
@@ -67,52 +66,25 @@ func (rd *ReminderData) SyncCalendar(calOptions *calendar.Options) error {
 			if item.Summary == "" {
 				continue
 			}
-			owned := false
-			if strings.HasPrefix(item.Summary, calendar.TitlePrefix) {
-				owned = true
-			}
-			fmt.Printf("  - %v | %v | owned=%v\n", item.Summary, item.Recurrence, owned)
+			fmt.Printf("  - %v | %v\n", item.Summary, item.Recurrence)
 		}
 	}
 	fmt.Println() // just print a blank line
 
+	// Delete existing reminder events from Cloud Calendar
 	// Note: Your might like to check your Calendar trash
 	// https://calendar.google.com/calendar/u/0/r/trash and clear it from
 	// time to time. Otherwise, this obstructs with visibility of newly
 	// added event in the API call.
-	logger.Info("Fetch all the events registered by reminder app (and some other matching the query).")
-	reminderEvents, _, _, err := calendar.FetchUpcomingEventsAndDetails(srv, 5, calendar.TitlePrefix)
+	logger.Info("Fetch all the events registered by reminder app.")
+	reminderEvents, _, _, err := calendar.FetchUpcomingEventsAndDetails(srv, 2, lookAheadYears, calendar.TitlePrefix)
 	if err != nil {
-		return fmt.Errorf("Unable to retrieve the events: %v", err)
+		return fmt.Errorf("Unable to retrieve the events: %w", err)
 	}
-	fmt.Printf("Listing matching events (%v) and deleting the ones registered by reminder app:\n", len(reminderEvents))
-	if len(reminderEvents) == 0 {
-		logger.Warn("No registered events found.")
-	} else {
-		deletionCount := 0
-		for _, item := range reminderEvents {
-			owned := false
-			if strings.HasPrefix(item.Summary, calendar.TitlePrefix) {
-				owned = true
-			}
-			fmt.Printf("  - %q -- %q (owned=%v)\n", calendar.EventString(item), item.Id, owned)
-			if owned {
-				if calOptions.DryMode {
-					logger.Warn(fmt.Sprintf("Dry mode is enabled; skipping deletion of the event %q.", item.Id))
-					// continue with next iteration
-					continue
-				}
-				if err := srv.Events.Delete("primary", item.Id).Do(); err != nil {
-					return fmt.Errorf("Couldn't delete the Calendar event %q | %q | %v", item.Id, item.Summary, err)
-				} else {
-					deletionCount += 1
-					fmt.Printf("    - Deleted the Calendar event %q | %q\n", item.Id, calendar.EventString(item))
-				}
-			}
-		}
-		if deletionCount > 0 {
-			fmt.Printf("\nWaring! Deletion count is %v; you might like to clear your trash manually by visiting https://calendar.google.com/calendar/u/0/r/trash\n", deletionCount)
-		}
+	fmt.Printf("Listing (%v) and deleting the events registered by the reminder app:\n", len(reminderEvents))
+	err = calendar.DeleteEvents(srv, reminderEvents, calOptions.DryMode)
+	if err != nil {
+		return fmt.Errorf("Unable to delete the events: %w", err)
 	}
 
 	// Add events to Cloud Calendar
@@ -121,15 +93,15 @@ func (rd *ReminderData) SyncCalendar(calOptions *calendar.Options) error {
 		return err
 	}
 	waitFor := 10 * time.Second
-	fmt.Printf("\nSyncing %v events (pending ones with due-date) to Google Calendar. Hit Ctrl-c if you don't want to do it at the moment. The process will wait for %v.\n", len(newEvents), waitFor)
+	fmt.Printf("\nAdding %v events (pending ones with due-date) to Google Calendar. Hit Ctrl-c if you don't want to do it at the moment. The process will wait for %v.\n", len(newEvents), waitFor)
 	fmt.Printf("waiting for %v...\n", waitFor)
 	time.Sleep(waitFor)
-	fmt.Println("Starting the syncing process.")
+	fmt.Println("Starting the event addition process.")
 	err = calendar.AddEvents(srv, newEvents, calOptions.DryMode)
 	if err != nil {
 		return err
 	}
-	fmt.Println("Done with syncing process.")
+	fmt.Println("Done with event addition process.")
 	return nil
 }
 

pkg/calendar/calendar.go

@@ -22,6 +22,33 @@ import (
 
 const TitlePrefix string = "[reminder] "
 
+// DeleteEvents delete passed cloud calendar events
+func DeleteEvents(srv *gc.Service, events []*gc.Event, dryMode bool) error {
+	if len(events) == 0 {
+		logger.Warn("No registered events found.")
+	} else {
+		deletionCount := 0
+		for _, item := range events {
+			fmt.Printf("  - %q -- %q\n", EventString(item), item.Id)
+			if dryMode {
+				logger.Warn(fmt.Sprintf("Dry mode is enabled; skipping deletion of the event %q.", item.Id))
+				// continue with next iteration
+				continue
+			}
+			if err := srv.Events.Delete("primary", item.Id).Do(); err != nil {
+				return fmt.Errorf("Couldn't delete the Calendar event %q | %q | %v", item.Id, item.Summary, err)
+			} else {
+				deletionCount += 1
+				fmt.Printf("    - Deleted the Calendar event %q | %q\n", item.Id, EventString(item))
+			}
+		}
+		if deletionCount > 0 {
+			logger.Warn(fmt.Sprintf("\nWaring! Deletion count is %v; you might like to clear your trash manually by visiting https://calendar.google.com/calendar/u/0/r/trash\n", deletionCount))
+		}
+	}
+	return nil
+}
+
 // AddEvents adds passed calendar events to the Cloud
 func AddEvents(srv *gc.Service, events []*gc.Event, dryMode bool) error {
 	for _, event := range events {
@@ -42,18 +69,18 @@ func AddEvents(srv *gc.Service, events []*gc.Event, dryMode bool) error {
 
 // FetchUpcomingEvents returns slice of `Event` objects for
 // specified number of years, with some default settings.
-func FetchUpcomingEventsAndDetails(srv *gc.Service, years int, query string) ([]*gc.Event, string, string, error) {
+func FetchUpcomingEventsAndDetails(srv *gc.Service, backYears int, aheadYears int, query string) ([]*gc.Event, string, string, error) {
 	// Get list of all upcomming events, with recurring events as a
 	// unit (and not as separate single events).
 	var allEvents []*gc.Event
 	var calendarDetails string
 	var timeZone string
 	currentTime := time.Now()
-	tStart := currentTime.Format(time.RFC3339)
-	tStop := currentTime.AddDate(years, 0, 0).Format(time.RFC3339) // until given number of years from now
+	tStart := currentTime.AddDate(-backYears, 0, 0).Format(time.RFC3339)
+	tStop := currentTime.AddDate(aheadYears, 0, 0).Format(time.RFC3339) // until given number of aheadYears from now
 	var pageToken string
 	maxPage := 25 // just a temporarily hard limit (not expected to be reached) to keep the loop bounded
-	logger.Info(fmt.Sprintf("Fetching Calendar items with query %q, of %d years starting from %s", query, years, tStart))
+	logger.Info(fmt.Sprintf("Fetching Calendar items with query %q, of %d years starting from %s", query, aheadYears, tStart))
 	for i := 0; i < maxPage; i++ {
 		logger.Info(fmt.Sprintf("Fetching Page-%d with token %q", i, pageToken))
 		eventsList := srv.Events.List("primary").