From 5a7f5e7076c872fbe5ab42afa197f043e08dc42d Mon Sep 17 00:00:00 2001
From: git <git@fredericofalcao.com>
Date: Mon, 16 Jun 2025 16:43:44 +0100
Subject: [PATCH] Updated "update" global db strategy, to allow for extra
 metadata fields to be unchanged

---
 main.js | 34 +++++++++++++++++++++++-----------
 1 file changed, 23 insertions(+), 11 deletions(-)

diff --git a/main.js b/main.js
index 8e0a7b9..095799d 100644
--- a/main.js
+++ b/main.js
@@ -21,16 +21,28 @@ function getDbPassword() {
   return base64Part.slice(-7,-1);
 }
 // Insert data into MariaDB
-async function insertToMariaDB(record) {
-  if (!['A', 'PTR', 'SRV','TXT'].includes(record.Type)) return;
+async function updateMariaDB(record) {
+   if (!['A', 'PTR', 'SRV', 'TXT'].includes(record.Type)) return;
+
+  const host = DB_USER;
+  const { Type, Name } = record;
   const dataStr = typeof record.Data === 'object' ? JSON.stringify(record.Data) : record.Data;
+
   try {
-    await dbPool.execute(
-      `REPLACE INTO ${DB_TABLE} (Host, Type, Name, Data) VALUES (?, ?, ?, ?);`,
-      [DB_USER, record.Type, record.Name, dataStr]
-    );
+    // Step 1: Check if a row exists
+    const [rows] = await dbPool.execute(`SELECT Data FROM ${DB_TABLE} WHERE Host = ? AND Type = ? AND Name = ?;`,[host, Type, Name]);
+
+    if (rows.length === 0) {
+      // No existing row → INSERT
+      await dbPool.execute(`INSERT INTO ${DB_TABLE} (Host, Type, Name, Data) VALUES (?, ?, ?, ?);`,[host, Type, Name, dataStr]);
+    } else if (rows[0].Data !== dataStr) {
+      // Row exists but Data is different → UPDATE
+      await dbPool.execute(`UPDATE ${DB_TABLE} SET Data = ? WHERE Host = ? AND Type = ? AND Name = ?;`,[dataStr, host, Type, Name]);
+    }
+    // else: existing data is the same → do nothing
+
   } catch (err) {
-    console.error("DB Insert Error:", err);
+    console.error("DB Update Error:", err);
   }
 }
 
@@ -81,7 +93,7 @@ function sniffmDNSLocalPackets() {
 				  // Add a new DEVICE to this SERVICE TYPE if needed
 				  if (!db.local.PTR[answer.name].includes(answer.data)) 
 					  db.local.PTR[answer.name].push(answer.data);
-            await insertToMariaDB({Type: answer.type,Name: answer.name,Data: db.local.PTR[answer.name]});
+            await updateMariaDB({Type: answer.type,Name: answer.name,Data: db.local.PTR[answer.name]});
 			  }		  	
 		  }
 		  // 2. Handle DEVICE IP resolution
@@ -89,7 +101,7 @@ function sniffmDNSLocalPackets() {
 			  // 2.1 Initialize ADDRESSES sub-database
 			  if (!db.local.A) db.local.A = {};
 			  db.local.A[answer.name] = answer.data;
-        await insertToMariaDB({Type: answer.type,Name: answer.name,Data: db.local.A[answer.name]});
+        await updateMariaDB({Type: answer.type,Name: answer.name,Data: db.local.A[answer.name]});
 		  }
 		  
 		  if (answer.type == "SRV") {
@@ -97,14 +109,14 @@ function sniffmDNSLocalPackets() {
 			  if (db.local[answer.name] === undefined) db.local[answer.name] = {"TXT":null,"SRV":null};
 			  
 			  db.local[answer.name][answer.type] = answer.data;
-        await insertToMariaDB({Type: answer.type,Name: answer.name,Data: db.local[answer.name][answer.type]});
+        await updateMariaDB({Type: answer.type,Name: answer.name,Data: db.local[answer.name][answer.type]});
 		  }
       if (answer.type == "TXT") {
 			  // Initialize this device / entry, if needed
 			  if (db.local[answer.name] === undefined) db.local[answer.name] = {"TXT":null,"SRV":null};
 			  
 			  db.local[answer.name][answer.type] = answer.data;
-        await insertToMariaDB({Type: answer.type,Name: answer.name,Data: db.local[answer.name][answer.type]});
+        await updateMariaDB({Type: answer.type,Name: answer.name,Data: db.local[answer.name][answer.type]});
 		  }
       
 		  saveDbToFile(db,DB_FILENAME);