⚡ add tool for getting property tree from fgfs

by using --httpd in fgfs

tools/fgfs_props_getter.nas

@@ -0,0 +1,58 @@
+# used to get property tree from fgfs by httpd
+# use --httpd=5500 to start fgfs
+# and use this script to get property tree
+# 2023/11/06 ValKmjolnir
+
+use module.libsock;
+use std.json;
+
+var socket = libsock.socket;
+var sd = socket.socket(socket.AF_INET, socket.SOCK_STREAM, socket.IPPROTO_TCP);
+
+while((var err = socket.connect(sd, "127.0.0.1", 5500))==socket.SOCKET_ERROR) {
+    println("[", os.time(), "] connect to 127.0.0.1:5500 failed: ", socket.errno());
+    unix.sleep(1);
+}
+println("[", os.time(), "] connect to 127.0.0.1:5500 succeeded");
+
+
+var header = "GET /json/ HTTP/1.1\n\r\n";
+var res = socket.send(sd, header);
+var message = socket.recv(sd, 1024);
+
+var total_source = message.str;
+var total_size = message.size;
+
+while(message.size==1024) {
+    message = socket.recv(sd, 1024);
+    total_source ~= message.str;
+    total_size += message.size;
+}
+
+socket.closesocket(sd);
+
+var A3E_position = find("{", total_source);
+var end_0_position = find("0\r\n\r\n", total_source);
+var props = substr(total_source, A3E_position, end_0_position-A3E_position);
+props = json.parse(props);
+json.check_error();
+
+var dfs = func(tree, indent = "") {
+    println(indent, "---------");
+    println(indent, "path : \"", tree.path, "\"");
+    println(indent, "name : \"", tree.name, "\"");
+    println(indent, "index : \"", tree.index, "\"");
+    println(indent, "type : \"", tree.type, "\"");
+    println(indent, "nChildren : \"", tree.nChildren, "\"");
+    println(indent, "---------");
+    
+    if (contains(tree, "children")) {
+        println(indent, "children :");
+        foreach(var i; tree.children) {
+            dfs(i, indent~"  ");
+        }
+    }
+
+}
+
+dfs(props);