implement database and mqtt client to cache node info

src/index.js

@@ -1,36 +1,28 @@
 const path = require('path');
-const axios = require('axios');
 const express = require('express');
-const NodeCache = require("node-cache");
-const cache = new NodeCache();
+const protobufjs = require("protobufjs");
+
+// create prisma db client
+const { PrismaClient } = require("@prisma/client");
+const prisma = new PrismaClient();
+
+// return big ints as string when using JSON.stringify
+BigInt.prototype.toJSON = function() {
+    return this.toString();
+}
+
+// load protobufs
+const root = new protobufjs.Root();
+root.resolvePath = (origin, target) => path.join(__dirname, "protos", target);
+root.loadSync('meshtastic/mqtt.proto');
+const HardwareModel = root.lookupEnum("HardwareModel");
+const Role = root.lookupEnum("Config.DeviceConfig.Role");
 
 const app = express();
 
 // serve files inside the public folder from /
 app.use('/', express.static(path.join(__dirname, 'public')));
 
-async function getCached(key, ttl, callback) {
-
-    // find data from cache
-    let data = cache.get(key);
-
-    // update cache
-    if(!data){
-        data = await callback();
-        cache.set(key, data, ttl);
-    }
-
-    // get expiration time in seconds
-    const cacheTtl = cache.getTtl(key);
-    const expiresIn = cacheTtl != null
-        ? Math.ceil((cacheTtl - Date.now()) / 1000)
-        : 0;
-
-    // return data
-    return [ data, expiresIn ];
-
-}
-
 app.get('/', async (req, res) => {
     res.sendFile(path.join(__dirname, 'public/index.html'));
 });
@@ -59,15 +51,18 @@ app.get('/api', async (req, res) => {
 app.get('/api/v1/nodes', async (req, res) => {
     try {
 
-        // get nodes from cache, or retrieve from api
-        const [ nodes, expiresIn ] = await getCached('nodes', 10, async () => {
-            const response = await axios.get("https://meshmap.net/nodes2.json");
-            return response.data;
-        });
+        // get nodes from db
+        const nodes = await prisma.node.findMany();
 
         res.json({
-            expires_in: expiresIn,
-            nodes: nodes,
+            nodes: nodes.map((node) => {
+                return {
+                    ...node,
+                    node_id_hex: "!" + node.node_id.toString(16),
+                    hardware_model_name: HardwareModel.valuesById[node.hardware_model] ?? "UNKNOWN",
+                    role_name: Role.valuesById[node.role] ?? "UNKNOWN",
+                }
+            }),
         });
 
     } catch(err) {