adding py-levin peer scanning

xmrnodes/helpers.py

@@ -1,3 +1,9 @@
+import sys
+import socket
+from levin.section import Section
+from levin.bucket import Bucket
+from levin.ctypes import *
+from levin.constants import LEVIN_SIGNATURE
 from requests import get as r_get
 from xmrnodes import config
 
@@ -47,3 +53,52 @@ def is_onion(url: str):
         return True
     else:
         return False
+
+def retrieve_peers():
+    try:
+        sock = socket.socket()
+        sock.connect((config.NODE_HOST, config.NODE_PORT))
+    except:
+        sys.stderr.write("unable to connect to %s:%d\n" % (config.NODE_HOST, config.NODE_PORT))
+        sys.exit()
+
+    bucket = Bucket.create_handshake_request()
+
+    sock.send(bucket.header())
+    sock.send(bucket.payload())
+
+    buckets = []
+    peers = []
+
+    while 1:
+        buffer = sock.recv(8)
+        if not buffer:
+            sys.stderr.write("Invalid response; exiting\n")
+            break
+
+        if not buffer.startswith(bytes(LEVIN_SIGNATURE)):
+            sys.stderr.write("Invalid response; exiting\n")
+            break
+
+        bucket = Bucket.from_buffer(signature=buffer, sock=sock)
+        buckets.append(bucket)
+
+        if bucket.command == 1001:
+            peers = bucket.get_peers() or []
+
+            for peer in peers:
+                try:
+                    print('')
+                    peers.append('http://{}:{}'.format(
+                        peer['ip'].ip, peer['port'].value
+                    ))
+                except:
+                    pass
+
+            sock.close()
+            break
+
+    if peers:
+        return peers
+    else:
+        return None