GUI: make SQLite writes compatible with older sqlite versions

gui/app.py

@@ -20,7 +20,9 @@ ADMIN_PASSWORD = os.environ.get("ADMIN_PASSWORD", "")
 
 
 def db_conn():
-    os.makedirs(os.path.dirname(DB_PATH), exist_ok=True)
+    db_dir = os.path.dirname(DB_PATH)
+    if db_dir:
+        os.makedirs(db_dir, exist_ok=True)
     conn = sqlite3.connect(DB_PATH)
     conn.row_factory = sqlite3.Row
     return conn
@@ -264,12 +266,15 @@ def new_peer():
 
     with db_conn() as conn:
         cur = conn.cursor()
-        cur.execute("""
-            INSERT INTO peers(name, public_key, client_address, advertised_routes)
-            VALUES (?,?,?,?)
-            ON CONFLICT(public_key)
-            DO UPDATE SET name=excluded.name, client_address=excluded.client_address, advertised_routes=excluded.advertised_routes
-        """, (name, client_pub, client_addr, routes))
+        cur.execute(
+            "UPDATE peers SET name=?, client_address=?, advertised_routes=? WHERE public_key=?",
+            (name, client_addr, routes, client_pub),
+        )
+        if cur.rowcount == 0:
+            cur.execute(
+                "INSERT INTO peers(name, public_key, client_address, advertised_routes) VALUES (?,?,?,?)",
+                (name, client_pub, client_addr, routes),
+            )
         conn.commit()
 
     return render_template(