move relayfee and dust_threshold to bitcoin.py

electrum/bitcoin.py

@@ -24,7 +24,7 @@
 # SOFTWARE.
 
 import hashlib
-from typing import List, Tuple
+from typing import List, Tuple, TYPE_CHECKING
 
 from .util import bfh, bh2u, BitcoinException, assert_bytes, to_bytes, inv_dict
 from . import version
@@ -33,6 +33,9 @@ from . import constants
 from . import ecc
 from .crypto import sha256d, sha256, hash_160, hmac_oneshot
 
+if TYPE_CHECKING:
+    from .network import Network
+
 
 ################################## transactions
 
@@ -147,6 +150,18 @@ def add_number_to_script(i: int) -> bytes:
     return bfh(push_script(script_num_to_hex(i)))
 
 
+def relayfee(network: 'Network'=None) -> int:
+    from .simple_config import FEERATE_DEFAULT_RELAY
+    MAX_RELAY_FEE = 50000
+    f = network.relay_fee if network and network.relay_fee else FEERATE_DEFAULT_RELAY
+    return min(f, MAX_RELAY_FEE)
+
+
+def dust_threshold(network: 'Network'=None) -> int:
+    # Change <= dust threshold is added to the tx fee
+    return 182 * 3 * relayfee(network) // 1000
+
+
 hash_encode = lambda x: bh2u(x[::-1])
 hash_decode = lambda x: bfh(x)[::-1]
 hmac_sha_512 = lambda x, y: hmac_oneshot(x, y, hashlib.sha512)