Create service method for sending emails to event attendees (#2955)

junlarsen · Copilot · web-flow · commit f2bf4c9efde9 · 2026-02-26T11:58:28.000+01:00
Co-authored-by: Copilot &lt;175728472+Copilot@users.noreply.github.com&gt;
diff --git a/apps/rpc/resources/email/event_message.mustache b/apps/rpc/resources/email/event_message.mustache
@@ -0,0 +1,35 @@
+<!DOCTYPE html>
+<html dir="ltr" lang="nb">
+
+<head>
+  <meta content="text/html; charset=UTF-8" http-equiv="Content-Type" />
+  <meta name="x-apple-disable-message-reformatting" />
+</head>
+
+<body style="background-color: rgb(255, 255, 255);">
+  <table align="center" width="100%" border="0" cellpadding="0" cellspacing="0" role="presentation"
+    style="max-width: 37.5em">
+    <tbody>
+      <tr style="width: 100%">
+        <td>
+          <h2>Viktig info om {{ eventName }}</h2>
+          <p>Dette er en melding fra arrangørene av <a href="{{ eventLink }}">{{ eventName }}</a> som du er påmeldt hos
+            Linjeforeningen Online.</p>
+          <p>{{ message }}</p>
+        </td>
+      </tr>
+
+      <tr style="width: 100%">
+        <td>
+          <h3 style="font-size: 0.9em; margin-top: 3rem">Linjeforeningen Online</h3>
+          <p style="font-size: 0.75em; color: gray">Du mottar denne e-posten fordi du er påmeldt arrangementet {{
+            eventName }}</p>
+          <p style="font-size: 0.75em; color: gray">Org. Nr. 992 548 045 &ndash; Høgskoleringen 5, 7034 Trondheim</p>
+          <p style="font-size: 0.75em; color: gray">Alle datoer er i norsk tid.</p>
+        </td>
+      </tr>
+    </tbody>
+  </table>
+</body>
+
+</html>
diff --git a/apps/rpc/src/modules/email/email-template.ts b/apps/rpc/src/modules/email/email-template.ts
@@ -11,6 +11,7 @@ export type EmailType =
   | "COMPANY_INVOICE_NOTIFICATION"
   | "FEEDBACK_FORM_LINK"
   | "EVENT_ATTENDANCE"
+  | "EVENT_MESSAGE"
   | "RECEIVED_MARK"
 
 export interface EmailTemplate<TData, TType extends EmailType> {
@@ -23,12 +24,6 @@ export type InferEmailData<TDef> = TDef extends EmailTemplate<infer TData, infer
 export type InferEmailType<TDef> =
   TDef extends EmailTemplate<infer TData, infer TType extends EmailType> ? TType : never
 
-export type CompanyCollaborationReceiptEmailTemplate = typeof emails.COMPANY_COLLABORATION_RECEIPT
-export type CompanyCollaborationNotificationEmailTemplate = typeof emails.COMPANY_COLLABORATION_NOTIFICATION
-export type CompanyInvoiceNotificationEmailTemplate = typeof emails.COMPANY_INVOICE_NOTIFICATION
-export type FeedbackFormLinkEmailTemplate = typeof emails.FEEDBACK_FORM_LINK
-export type AnyEmailTemplate = CompanyCollaborationReceiptEmailTemplate
-
 export function createEmailTemplate<const TData, const TType extends EmailType>(
   definition: EmailTemplate<TData, TType>
 ): EmailTemplate<TData, TType> {
@@ -124,6 +119,16 @@ export const emails = {
       }),
     getTemplate: async () => fsp.readFile(path.join(templates, "event_attendance.mustache"), "utf-8"),
   }),
+  EVENT_MESSAGE: createEmailTemplate({
+    type: "EVENT_MESSAGE",
+    getSchema: () =>
+      z.object({
+        eventName: z.string(),
+        eventLink: z.string().url(),
+        message: z.string(),
+      }),
+    getTemplate: async () => fsp.readFile(path.join(templates, "event_message.mustache"), "utf-8"),
+  }),
   RECEIVED_MARK: createEmailTemplate({
     type: "RECEIVED_MARK",
     getSchema: () =>
diff --git a/apps/rpc/src/modules/event/attendance-service.ts b/apps/rpc/src/modules/event/attendance-service.ts
@@ -18,7 +18,6 @@ import {
   AttendeeWriteSchema,
   DEFAULT_MARK_DURATION,
   type Event,
-  type GroupType,
   type Membership,
   type TaskId,
   type User,
@@ -27,6 +26,7 @@ import {
   getMembershipGrade,
   hasAttendeePaid,
   isAttendable,
+  findFirstHostingGroupEmail,
 } from "@dotkomonline/types"
 import { createAbsoluteEventPageUrl, createPoolName, getCurrentUTC, ogJoin, slugify } from "@dotkomonline/utils"
 import {
@@ -258,6 +258,8 @@ export interface AttendanceService {
     mergeTime: TZDate | null
   ): Promise<TaskId | null>
   executeMergeEventPoolsTask(handle: DBHandle, task: InferTaskData<MergeAttendancePoolsTaskDefinition>): Promise<void>
+
+  notifyAttendees(handle: DBHandle, attendanceId: AttendanceId, message: string): Promise<void>
 }
 
 export function getAttendanceService(
@@ -1438,12 +1440,7 @@ export function getAttendanceService(
           return
         }
 
-        const validGroupTypes: GroupType[] = ["COMMITTEE", "NODE_COMMITTEE"]
-
-        const hostingGroupEmail =
-          event.hostingGroups.filter((group) => group.email && validGroupTypes.includes(group.type)).at(0)?.email ??
-          "bedkom@online.ntnu.no"
-
+        const hostingGroupEmail = findFirstHostingGroupEmail(event) ?? "bedkom@online.ntnu.no"
         logger.info(
           "Sending feedback form email for Event(ID=%s) to %d attendees from email %s",
           event.id,
@@ -1613,6 +1610,59 @@ export function getAttendanceService(
       await attendanceRepository.updateAttendeeAttendancePoolIdByAttendancePoolIds(handle, mergeablePoolIds, pool.id)
       await attendanceRepository.deleteAttendancePoolsByIds(handle, mergeablePoolIds)
     },
+    async notifyAttendees(handle, attendanceId, message) {
+      const attendance = await this.getAttendanceById(handle, attendanceId)
+      const event = await eventService.getByAttendanceId(handle, attendanceId)
+      if (isBefore(getCurrentUTC(), attendance.registerStart)) {
+        throw new IllegalStateError(`Cannot send message to attendees for Attendance(ID=${attendance.id}) before start`)
+      }
+
+      const hostingGroupEmail = findFirstHostingGroupEmail(event)
+      if (hostingGroupEmail === null) {
+        logger.warn(
+          "Notification email sent for Event(ID=%s, Name=%s) did not have sufficient organizer email so %s was used.",
+          event.id,
+          event.title,
+          DEFAULT_EMAIL_SOURCE
+        )
+      }
+      const sourceEmail = hostingGroupEmail ?? DEFAULT_EMAIL_SOURCE
+
+      // In order to keep email sizes relatively small, and to prevent spam detection we batch the emails with 25 BCC recipients at a time
+      const batchSize = 25
+      for (let batchStartIndex = 0; batchStartIndex < attendance.attendees.length; batchStartIndex += batchSize) {
+        const attendees = attendance.attendees.slice(batchStartIndex, batchStartIndex + batchSize)
+        const attendeeEmails = attendees.map((a) => a.user.email).filter((e) => e !== null)
+
+        const currentBatchIndex = Math.floor(batchStartIndex / batchSize) + 1
+        const totalBatches = Math.ceil(attendance.attendees.length / batchSize)
+
+        logger.info(
+          "Scheduling emails %s..%s in batch %s/%s for notification for Event(ID=%s, Name=%s)",
+          batchStartIndex + 1,
+          batchStartIndex + attendees.length,
+          currentBatchIndex,
+          totalBatches,
+          event.id,
+          event.title
+        )
+
+        await emailService.send(
+          sourceEmail,
+          [sourceEmail],
+          [],
+          [],
+          attendeeEmails,
+          `Viktig melding om ${event.title}`,
+          emails.EVENT_MESSAGE,
+          {
+            eventName: event.title,
+            eventLink: createAbsoluteEventPageUrl(configuration.WEB_PUBLIC_ORIGIN, event.id, event.title),
+            message,
+          }
+        )
+      }
+    },
   }
 }
 
diff --git a/packages/types/src/event.ts b/packages/types/src/event.ts
@@ -6,7 +6,7 @@ import { AttendanceSchema, AttendanceSummarySchema } from "./attendance"
 import { CompanySchema } from "./company"
 import { FeedbackFormSchema } from "./feedback-form"
 import { buildAnyOfFilter, buildDateRangeFilter, buildSearchFilter, createSortOrder } from "./filters"
-import { GroupSchema } from "./group"
+import { GroupSchema, type GroupType } from "./group"
 
 /**
  * @packageDocumentation
@@ -183,3 +183,8 @@ export const getDefaultFeedbackAnswerDeadline = (eventEnd: Date, timezone: strin
 }
 
 export const EVENT_IMAGE_MAX_SIZE_KIB = 5 * 1024
+
+export function findFirstHostingGroupEmail(event: Event): string | null {
+  const validGroupTypes: GroupType[] = ["COMMITTEE", "NODE_COMMITTEE"]
+  return event.hostingGroups.filter((group) => group.email && validGroupTypes.includes(group.type)).at(0)?.email ?? null
+}
