support fetching direct messages between two nodes

src/index.js

@@ -472,15 +472,21 @@ app.get('/api/v1/text-messages', async (req, res) => {
         const from = req.query.from ?? undefined;
         const channelId = req.query.channel_id ?? undefined;
         const gatewayId = req.query.gateway_id ?? undefined;
+        const directMessageNodeIds = req.query.direct_message_node_ids?.split(",") ?? undefined;
         const lastId = req.query.last_id ? parseInt(req.query.last_id) : undefined;
         const count = req.query.count ? parseInt(req.query.count) : 50;
         const order = req.query.order ?? "asc";
 
-        // get text messages from db
-        const textMessages = await prisma.textMessage.findMany({
-            where: {
-                to: to,
-                from: from,
+        // if direct message node ids are provided, there should be exactly two node ids
+        if(directMessageNodeIds !== undefined && directMessageNodeIds.length !== 2){
+            res.status(400).json({
+                message: "direct_message_node_ids requires 2 node ids separated by a comma.",
+            });
+            return;
+        }
+
+        // default where clauses that should always be used for filtering
+        var where = {
             channel_id: channelId,
             gateway_id: gatewayId,
             // when ordered oldest to newest (asc), only get records after last id
@@ -490,7 +496,37 @@ app.get('/api/v1/text-messages', async (req, res) => {
             } : {
                 lt: lastId,
             },
+        };
+
+        // if direct message node ids are provided, we expect exactly 2 node ids
+        if(directMessageNodeIds !== undefined && directMessageNodeIds.length === 2){
+            // filter message by "to -> from" or "from -> to"
+            const [firstNodeId, secondNodeId] = directMessageNodeIds;
+            where = {
+                AND: where,
+                OR: [
+                    {
+                        to: firstNodeId,
+                        from: secondNodeId,
                     },
+                    {
+                        to: secondNodeId,
+                        from: firstNodeId,
+                    },
+                ],
+            };
+        } else {
+            // filter by to and from
+            where = {
+                ...where,
+                to: to,
+                from: from,
+            };
+        }
+
+        // get text messages from db
+        const textMessages = await prisma.textMessage.findMany({
+            where: where,
             orderBy: {
                 id: order,
             },

src/public/text-messages-embed.html

@@ -110,6 +110,7 @@
             this.from = queryParams.get('from');
             this.channelId = queryParams.get('channel_id');
             this.gatewayId = queryParams.get('gateway_id');
+            this.directMessageNodeIds = queryParams.get('direct_message_node_ids');
             this.count = queryParams.get('count');
 
             // listen for scrolling of messages list
@@ -170,6 +171,7 @@
                             from: this.from,
                             channel_id: this.channelId,
                             gateway_id: this.gatewayId,
+                            direct_message_node_ids: this.directMessageNodeIds,
                             count: this.count,
                             order: "desc",
                             last_id: this.oldestMessageId,
@@ -217,6 +219,7 @@
                             from: this.from,
                             channel_id: this.channelId,
                             gateway_id: this.gatewayId,
+                            direct_message_node_ids: this.directMessageNodeIds,
                             count: this.count,
                             order: "asc",
                             last_id: this.latestMessageId,