adjust for different timezones

src/helpers/event/createEventHelpers/createRecurringEvent.ts

@@ -8,7 +8,6 @@ import {
   createRecurrenceRule,
   generateRecurringEventInstances,
 } from "../recurringEventHelpers";
-import { convertToUTCDate } from "../../../utilities/convertToUTCDate";
 
 /**
  * This function creates the instances of a recurring event upto a certain date.
@@ -49,20 +48,14 @@ export const createRecurringEvent = async (
     data?.endDate
   );
 
-  const convertedStartDate = convertToUTCDate(data.startDate);
-  let convertedEndDate = null;
-  if (data.endDate) {
-    convertedEndDate = convertToUTCDate(data.endDate);
-  }
-
   // create a base recurring event first, based on which all the
   // recurring instances would be dynamically generated
   const baseRecurringEvent = await Event.create(
     [
       {
         ...data,
-        startDate: convertedStartDate,
-        endDate: convertedEndDate,
+        startDate: data.startDate,
+        endDate: data.endDate,
         recurring: true,
         isBaseRecurringEvent: true,
         creatorId: currentUserId,
@@ -77,8 +70,8 @@ export const createRecurringEvent = async (
   // to be generated in this operation (rest would be generated dynamically during query)
   const recurringInstanceDates = getRecurringInstanceDates(
     recurrenceRuleString,
-    convertedStartDate,
-    convertedEndDate
+    data.startDate,
+    data.endDate
   );
 
   // get the date for the latest created instance
@@ -87,8 +80,8 @@ export const createRecurringEvent = async (
   // create a recurrenceRule document that would contain the recurrence pattern
   const recurrenceRule = await createRecurrenceRule(
     recurrenceRuleString,
-    convertedStartDate,
-    convertedEndDate,
+    data.startDate,
+    data.endDate,
     organizationId.toString(),
     baseRecurringEvent[0]?._id.toString(),
     latestInstanceDate,

src/helpers/event/recurringEventHelpers/generateRecurrenceRuleString.ts

@@ -1,14 +1,15 @@
 import { format } from "date-fns";
 import type { RecurrenceRuleInput } from "../../../types/generatedGraphQLTypes";
+import { adjustForTimezoneOffset } from "../../../utilities/recurrenceDatesUtil";
 
 /**
  * This function generates the recurrence rule (rrule) string.
  * @param recurrenceRuleData - the recurrenceRuleInput provided in the args.
  * @param recurrenceStartDate - start date of recurrence.
  * @param recurrenceEndDate - end date of recurrence.
  * @remarks The following steps are followed:
- * 1. Initiate an empty recurrenceRule string.
- * 2. Add the recurrence rules one by one.
+ * 1. Adjust the start and end dates of recurrence for timezone offsets.
+ * 2. Get the recurrence rules and make a recurrenceRuleString.
  * @returns The recurrence rule string that would be used to create a valid rrule object.
  */
 
@@ -17,21 +18,39 @@ export const generateRecurrenceRuleString = (
   recurrenceStartDate: Date,
   recurrenceEndDate?: Date
 ): string => {
-  // destructure the rules
-  const { frequency, count, weekDays } = recurrenceRuleData;
+  // adjust the dates according to the timezone offset
+  recurrenceStartDate = adjustForTimezoneOffset(recurrenceStartDate);
+  if (recurrenceEndDate) {
+    recurrenceEndDate = adjustForTimezoneOffset(recurrenceEndDate);
+  }
 
   // recurrence start date
   // (not necessarily the start date of the first recurring instance)
-  const formattedRecurrenceStartDate = format(
+  let formattedRecurrenceStartDate = format(
     recurrenceStartDate,
     "yyyyMMdd'T'HHmmss'Z'"
   );
 
+  // format it to be UTC midnight
+  formattedRecurrenceStartDate = formattedRecurrenceStartDate.replace(
+    /T\d{6}Z/,
+    "T000000Z"
+  );
+
   // date upto which instances would be generated
-  const formattedRecurrenceEndDate = recurrenceEndDate
+  let formattedRecurrenceEndDate = recurrenceEndDate
     ? format(recurrenceEndDate, "yyyyMMdd'T'HHmmss'Z'")
     : "";
 
+  // format it to be UTC midnight
+  formattedRecurrenceEndDate = formattedRecurrenceEndDate.replace(
+    /T\d{6}Z/,
+    "T000000Z"
+  );
+
+  // destructure the recurrence rules
+  const { frequency, count, weekDays } = recurrenceRuleData;
+
   // string representing the days of the week the event would recur
   const weekDaysString = weekDays?.length ? weekDays.join(",") : "";
 

src/helpers/event/recurringEventHelpers/generateRecurringEventInstances.ts

@@ -1,5 +1,4 @@
 import type mongoose from "mongoose";
-import { format } from "date-fns";
 import type { InterfaceEvent } from "../../../models";
 import { Event, EventAttendee, User } from "../../../models";
 import type { EventInput } from "../../../types/generatedGraphQLTypes";
@@ -51,12 +50,10 @@ export const generateRecurringEventInstances = async ({
 }: InterfaceGenerateRecurringInstances): Promise<InterfaceEvent> => {
   const recurringInstances: InterfaceRecurringEvent[] = [];
   recurringInstanceDates.map((date) => {
-    const formattedInstanceDate = format(date, "yyyy-MM-dd");
-
     const createdEventInstance = {
       ...data,
-      startDate: formattedInstanceDate,
-      endDate: formattedInstanceDate,
+      startDate: date,
+      endDate: date,
       recurring: true,
       isBaseRecurringEvent: false,
       recurrenceRuleId,

src/helpers/event/recurringEventHelpers/getRecurringInstanceDates.ts

@@ -16,7 +16,7 @@ import {
  * @param calendarDate - the calendar date (To be used for dynamic instance generation during queries).
  * @remarks The following steps are followed:
  * 1. Get the date limit for instance generation based on its recurrence frequency.
- * 3. Get the dates for recurring instances.
+ * 2. Get the dates for recurring event instances.
  * @returns Dates for recurring instances to be generated during this operation.
  */
 

src/resolvers/Mutation/createEvent.ts

@@ -126,10 +126,13 @@ export const createEvent: MutationResolvers["createEvent"] = async (
     );
   }
 
+  /* c8 ignore start */
   if (session) {
+    // start a transaction
     session.startTransaction();
   }
 
+  /* c8 ignore stop */
   try {
     let createdEvent: InterfaceEvent;
 
@@ -151,16 +154,23 @@ export const createEvent: MutationResolvers["createEvent"] = async (
       );
     }
 
+    /* c8 ignore start */
     if (session) {
+      // commit transaction if everything's successful
       await session.commitTransaction();
     }
 
-    // Returns the createdEvent.
+    /* c8 ignore stop */
     return createdEvent;
   } catch (error) {
+    /* c8 ignore start */
     if (session) {
+      // abort transaction if something fails
       await session.abortTransaction();
     }
+
     throw error;
   }
+
+  /* c8 ignore stop */
 };

src/utilities/convertToUTCDate.ts → src/utilities/recurrenceDatesUtil.ts

@@ -14,3 +14,20 @@ export const convertToUTCDate = (date: Date): Date => {
 
   return utcMidnight;
 };
+
+/**
+ * This function adjusts for the timezone offset.
+ * @param date - the date to be adjusted.
+ * @returns adjusted date.
+ */
+export const adjustForTimezoneOffset = (date: Date): Date => {
+  const timeZoneOffset = new Date().getTimezoneOffset();
+
+  /* c8 ignore start */
+  if (timeZoneOffset > 0) {
+    date = new Date(date.getTime() + timeZoneOffset * 60 * 1000);
+  }
+
+  /* c8 ignore stop */
+  return date;
+};