Recipient unsent messages (#73)

Co-authored-by: me <me@kentcdodds.com>
Co-authored-by: Cursor Agent <cursoragent@cursor.com>

Author: kentcdodds

.cursor/rules/agents.mdc

@@ -0,0 +1,5 @@
+# Agent instructions
+
+- Use typed SQL (generated `sql` helpers with `prisma.$queryRawTyped`).
+- Do not use `prisma.$queryRaw` or `Prisma.sql`.
+- Exception: Prisma typed SQL filenames must be valid JS identifiers (no dashes), so the lower-kebab-case rule does not apply under `prisma/sql/`.

app/routes/_app+/recipients+/_layout.tsx

@@ -8,6 +8,7 @@ import { GeneralErrorBoundary } from '#app/components/error-boundary.tsx'
 import { requireUserId } from '#app/utils/auth.server.js'
 import { CronParseError, getScheduleWindow } from '#app/utils/cron.server.ts'
 import { prisma } from '#app/utils/db.server.ts'
+import { getunsentmessagecounts } from '#app/utils/prisma-generated.server/sql.ts'
 import {
 	NEXT_SCHEDULE_SENTINEL_DATE,
 	PREV_SCHEDULE_SENTINEL_DATE,
@@ -36,6 +37,7 @@ function formatScheduleDisplay(date: Date, timeZone: string) {
 
 export async function loader({ request }: LoaderFunctionArgs) {
 	const userId = await requireUserId(request)
+
 	const recipients = await prisma.recipient.findMany({
 		select: {
 			id: true,
@@ -46,10 +48,25 @@ export async function loader({ request }: LoaderFunctionArgs) {
 			disabled: true,
 			prevScheduledAt: true,
 			nextScheduledAt: true,
-			_count: { select: { messages: { where: { sentAt: null } } } },
 		},
-		where: { userId },
+		where: {
+			userId,
+		},
+		orderBy: { id: 'asc' },
 	})
+	const recipientIds = recipients.map((recipient) => recipient.id)
+	const messageCounts = recipientIds.length
+		? await prisma.$queryRawTyped(
+				getunsentmessagecounts(JSON.stringify(recipientIds)),
+			)
+		: []
+	const messageCountByRecipientId = new Map(
+		messageCounts.map((row) => [row.recipientId, Number(row.unsentCount ?? 0)]),
+	)
+	const recipientsWithCounts = recipients.map((recipient) => ({
+		...recipient,
+		messageCount: messageCountByRecipientId.get(recipient.id) ?? 0,
+	}))
 
 	const now = new Date()
 	const scheduleUpdates: Array<{
@@ -59,7 +76,7 @@ export async function loader({ request }: LoaderFunctionArgs) {
 	}> = []
 
 	// Ensure we have a schedule window for sorting/display
-	const sortedRecipients = recipients
+	const sortedRecipients = recipientsWithCounts
 		.map((recipient) => {
 			let nextScheduledAt = recipient.nextScheduledAt
 			let prevScheduledAt = recipient.prevScheduledAt

app/routes/_app+/recipients+/index.tsx

@@ -67,7 +67,7 @@ export default function RecipientsIndexRoute() {
 				{hasRecipients ? (
 					<div className="md:divide-border space-y-4 md:space-y-0 md:divide-y">
 						{recipients.map((recipient) => {
-							const messageCount = recipient._count.messages
+							const messageCount = recipient.messageCount
 							const messageLabel = messageCount === 1 ? 'message' : 'messages'
 							const messageText = `${messageCount} ${messageLabel}`
 							const messagePreparedText = `${messageText} prepared`

prisma/migrations/20260202160000-recipient-message-indexes/migration.sql

@@ -0,0 +1,6 @@
+-- CreateIndex
+CREATE INDEX "recipient_by_user" ON "Recipient"("userId", "id");
+
+-- CreateIndex
+CREATE INDEX "message_unsent_by_recipient" ON "Message"("recipientId")
+WHERE "sentAt" IS NULL;

prisma/schema.prisma

@@ -147,6 +147,7 @@ model Recipient {
 
   // non-unique foreign key
   @@index([userId])
+  @@index([userId, id], name: "recipient_by_user")
   // Optimized composite index for cron query: equality cols first, then range, then join
   @@index([verified, disabled, nextScheduledAt, userId], name: "Recipient_cron_query_idx")
 }

prisma/sql/getunsentmessagecounts.sql

@@ -0,0 +1,10 @@
+-- Count unsent messages for a list of recipient IDs.
+--
+-- @param {String} $1 - JSON array of recipient ids
+SELECT
+  recipientId,
+  CAST(COUNT(*) AS INTEGER) AS unsentCount
+FROM Message INDEXED BY message_unsent_by_recipient
+WHERE sentAt IS NULL
+  AND recipientId IN (SELECT value FROM json_each($1))
+GROUP BY recipientId;

scripts/benchmark-performance.ts

@@ -3,10 +3,14 @@ import { performance } from 'node:perf_hooks'
 import { parseArgs } from 'node:util'
 import { CronParseError, getScheduleWindow } from '#app/utils/cron.server.ts'
 import { prisma } from '#app/utils/db.server.ts'
-import { getrecipientsforcron } from '#app/utils/prisma-generated.server/sql.ts'
+import {
+	getrecipientsforcron,
+	getunsentmessagecounts,
+} from '#app/utils/prisma-generated.server/sql.ts'
 import { NEXT_SCHEDULE_SENTINEL_DATE } from '#app/utils/schedule-constants.server.ts'
 
 const MESSAGES_PER_PAGE = 100
+const RECIPIENTS_PAGE_SIZE = 200
 
 type Summary = {
 	min: number
@@ -120,14 +124,31 @@ async function benchmarkRecipientsList(
 				disabled: true,
 				prevScheduledAt: true,
 				nextScheduledAt: true,
-				_count: { select: { messages: { where: { sentAt: null } } } },
 			},
+			orderBy: { id: 'asc' },
+			take: RECIPIENTS_PAGE_SIZE,
 		})
+		const recipientIds = recipients.map((recipient) => recipient.id)
+		const messageCounts = recipientIds.length
+			? await prisma.$queryRawTyped(
+					getunsentmessagecounts(JSON.stringify(recipientIds)),
+				)
+			: []
+		const messageCountByRecipientId = new Map(
+			messageCounts.map((row) => [
+				row.recipientId,
+				Number(row.unsentCount ?? 0),
+			]),
+		)
+		const recipientsWithCounts = recipients.map((recipient) => ({
+			...recipient,
+			messageCount: messageCountByRecipientId.get(recipient.id) ?? 0,
+		}))
 		const queryMs = performance.now() - queryStart
 
 		const computeStart = performance.now()
 		let errors = 0
-		const sortedRecipients = recipients
+		const sortedRecipients = recipientsWithCounts
 			.map((recipient) => {
 				try {
 					const isSentinel =
@@ -184,7 +205,7 @@ async function benchmarkRecipientsList(
 		querySamples.push(queryMs)
 		computeSamples.push(computeMs)
 		cronErrors.push(errors)
-		lastCount = recipients.length
+		lastCount = recipientsWithCounts.length
 	}
 
 	return {