follow-up 387f6db3b6 - py2 fixes

lib/daemon.py

@@ -33,8 +33,8 @@ from .jsonrpc import VerifyingJSONRPCServer
 
 from version import ELECTRUM_VERSION
 from network import Network
-from util import json_decode, DaemonThread
+from util import (json_decode, DaemonThread, print_msg, print_error,
-from util import print_msg, print_error, print_stderr, UserCancelled
+                  print_stderr, UserCancelled, to_string, int_to_bytes)
 from wallet import Wallet
 from storage import WalletStorage
 from commands import known_commands, Commands
@@ -102,7 +102,7 @@ def get_rpc_credentials(config):
         nbytes = bits // 8 + (bits % 8 > 0)
         pw_int = ecdsa.util.randrange(pow(2, bits))
         pw_b64 = base64.b64encode(
-            pw_int.to_bytes(nbytes, 'big'), b'-_')
+            int_to_bytes(pw_int, nbytes, 'big'), b'-_')
         rpc_password = to_string(pw_b64, 'ascii')
         config.set_key('rpcuser', rpc_user)
         config.set_key('rpcpassword', rpc_password, save=True)

lib/jsonrpc.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python3
+#!/usr/bin/env python2
 #
 # Electrum - lightweight Bitcoin client
 # Copyright (C) 2018 Thomas Voegtlin
@@ -52,6 +52,8 @@ class VerifyingJSONRPCServer(SimpleJSONRPCServer):
 
         self.rpc_user = kargs['rpc_user']
         self.rpc_password = kargs['rpc_password']
+        del kargs['rpc_user']
+        del kargs['rpc_password']
 
         class VerifyingRequestHandler(SimpleJSONRPCRequestHandler):
             def parse_request(myself):

lib/util.py

@@ -247,6 +247,38 @@ def android_check_data_dir():
 def get_headers_dir(config):
     return android_headers_dir() if 'ANDROID_DATA' in os.environ else config.path
 
+def to_string(x, enc):
+    if isinstance(x, (bytes, bytearray)):
+        return x.decode(enc)
+    if isinstance(x, str):
+        return x
+    else:
+        raise TypeError("Not a string or bytes like object")
+
+def to_bytes(something, encoding='utf8'):
+    """
+    cast string to bytes() like object, but for python2 support it's bytearray copy
+    """
+    if isinstance(something, bytes):
+        return something
+    if isinstance(something, str) or isinstance(something, unicode):
+        return something.encode(encoding)
+    elif isinstance(something, bytearray):
+        return bytes(something)
+    else:
+        raise TypeError("Not a string or bytes like object")
+
+# based on https://stackoverflow.com/questions/16022556/has-python-3-to-bytes-been-back-ported-to-python-2-7
+def int_to_bytes(n, length, endianess='big'):
+    hex_n = '%x' % n
+    hex_n2 = '0'*(len(hex_n) % 2) + hex_n
+    left_padded_hex_n = hex_n2.zfill(length*2)
+    if len(left_padded_hex_n) > length*2:
+        raise OverflowError()
+    assert len(left_padded_hex_n) == length*2
+    bytes_n = left_padded_hex_n.decode('hex')
+    return bytes_n if endianess == 'big' else bytes_n[::-1]
+
 def user_dir():
     if 'ANDROID_DATA' in os.environ:
         return android_check_data_dir()