From 8d482b007f33616cf807d686b6c070ddb1d57bcc Mon Sep 17 00:00:00 2001
From: Leeroy Brun <leeroy.brun@gmail.com>
Date: Tue, 30 Dec 2025 12:11:58 +0100
Subject: [PATCH] Add pagination to session messages endpoint

Introduced optional 'limit' and 'beforeSeq' query parameters to the session messages route, enabling pagination. The response now includes 'hasMore' and 'nextBeforeSeq' fields to facilitate client-side navigation through message history.
---
 sources/app/api/routes/sessionRoutes.ts | 30 ++++++++++++++++++++-----
 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/sources/app/api/routes/sessionRoutes.ts b/sources/app/api/routes/sessionRoutes.ts
index e4f9e7a9..a4de8fda 100644
--- a/sources/app/api/routes/sessionRoutes.ts
+++ b/sources/app/api/routes/sessionRoutes.ts
@@ -309,12 +309,17 @@ export function sessionRoutes(app: Fastify) {
         schema: {
             params: z.object({
                 sessionId: z.string()
-            })
+            }),
+            querystring: z.object({
+                limit: z.coerce.number().int().min(1).max(500).default(150),
+                beforeSeq: z.coerce.number().int().min(1).optional(),
+            }).optional()
         },
         preHandler: app.authenticate
     }, async (request, reply) => {
         const userId = request.userId;
         const { sessionId } = request.params;
+        const { limit = 150, beforeSeq } = request.query || {};
 
         // Verify session belongs to user
         const session = await db.session.findFirst({
@@ -328,10 +333,15 @@ export function sessionRoutes(app: Fastify) {
             return reply.code(404).send({ error: 'Session not found' });
         }
 
+        const where: Prisma.SessionMessageWhereInput = { sessionId };
+        if (beforeSeq !== undefined) {
+            where.seq = { lt: beforeSeq };
+        }
+
         const messages = await db.sessionMessage.findMany({
-            where: { sessionId },
-            orderBy: { createdAt: 'desc' },
-            take: 150,
+            where,
+            orderBy: { seq: 'desc' },
+            take: limit + 1,
             select: {
                 id: true,
                 seq: true,
@@ -342,15 +352,23 @@ export function sessionRoutes(app: Fastify) {
             }
         });
 
+        const hasMore = messages.length > limit;
+        const resultMessages = hasMore ? messages.slice(0, limit) : messages;
+        const nextBeforeSeq = hasMore && resultMessages.length > 0
+            ? resultMessages[resultMessages.length - 1].seq
+            : null;
+
         return reply.send({
-            messages: messages.map((v) => ({
+            messages: resultMessages.map((v) => ({
                 id: v.id,
                 seq: v.seq,
                 content: v.content,
                 localId: v.localId,
                 createdAt: v.createdAt.getTime(),
                 updatedAt: v.updatedAt.getTime()
-            }))
+            })),
+            hasMore,
+            nextBeforeSeq
         });
     });