erc20-faucet

commit 59c1460b2c9a0f176ef63281efa014a9d1caa953
parent 3e2629eba7e6d506cec1fdde262282777335d529
Author: nolash <dev@holbrook.no>
Date:   Sun,  2 May 2021 11:57:52 +0200

Repair hex parse in method lookup

Diffstat:
M
python/erc20_faucet/faucet.py
 | 
2
++
M
python/erc20_faucet/interface.py
 | 
52
+++++++++++++++++++++++++++++++++++++++++++++++++++-
M
python/setup.cfg
 | 
2
+-
M
python/tests/test_basic.py
 | 
10
++++++++++

4 files changed, 64 insertions(+), 2 deletions(-)
diff --git a/python/erc20_faucet/faucet.py b/python/erc20_faucet/faucet.py
@@ -76,6 +76,8 @@ class SingleShotFaucet(Faucet):
 
     # TODO: allow multiple overriders
     def constructor(self, sender_address, token, store, accounts_index, overrider):
+        if accounts_index == None:
+            accounts_index = ZERO_ADDRESS
         code = SingleShotFaucet.bytecode()
         enc = ABIContractEncoder()
         enc.uint256(0x80)
diff --git a/python/erc20_faucet/interface.py b/python/erc20_faucet/interface.py
@@ -1,7 +1,9 @@
 # standard imports
 import logging
+import copy
 
 # external imports
+import sha3
 from chainlib.eth.tx import TxFactory
 from chainlib.eth.constant import ZERO_ADDRESS
 from chainlib.eth.contract import (
@@ -13,13 +15,58 @@ from chainlib.eth.tx import (
         TxFormat,
         )
 from chainlib.jsonrpc import jsonrpc_template
-from hexathon import add_0x
+from hexathon import (
+        add_0x,
+        strip_0x,
+        )
+from potaahto.symbols import snake_and_camel_s
 
 logg = logging.getLogger().getChild(__name__)
 
 
 class Faucet(TxFactory):
 
+    __signatures = {
+        'give_to': 'giveTo(address)',
+        'token_amount': 'tokenAmount()',
+        'token': 'token()',
+            }
+    __signatures_reverse = None
+
+
+    @classmethod
+    def method_for(self, b):
+        if type(b).__name__ == 'str':
+            b = bytes.fromhex(strip_0x(b))
+        if len(b) < 4:
+            return None
+        return self.__signatures_reverse.get(b[:4])
+
+
+    @classmethod
+    def signature_for(self, s):
+        return self.__signatures.get(s)
+
+
+    @classmethod
+    def build_signatures(cls):
+        if cls.__signatures_reverse != None:
+            return
+        cls.__signatures_reverse = {}
+
+        for (k, v) in copy.copy(Faucet.__signatures).items():
+            (x, y) = snake_and_camel_s(k)
+            h = sha3.keccak_256()
+            h.update(v.encode('utf-8'))
+            z = h.digest()
+            sig = z[:4]
+            Faucet.__signatures[x] = sig
+            Faucet.__signatures[y] = sig
+            Faucet.__signatures_reverse[sig] = x
+
+        return True
+
+
     def give_to(self, contract_address, sender_address, beneficiary_address, tx_format=TxFormat.JSONRPC):
         enc = ABIContractEncoder()
         enc.method('giveTo')
@@ -100,3 +147,6 @@ class Faucet(TxFactory):
     @classmethod
     def parse_token_amount(self, v):
         return abi_decode_single(ABIContractType.UINT256, v)
+
+
+Faucet.build_signatures()
diff --git a/python/setup.cfg b/python/setup.cfg
@@ -1,6 +1,6 @@
 [metadata]
 name = erc20-faucet
-version = 0.2.1a1
+version = 0.2.1a2
 description = ERC20 token faucet
 author = Louis Holbrook
 author_email = dev@holbrook.no
diff --git a/python/tests/test_basic.py b/python/tests/test_basic.py
@@ -114,5 +114,15 @@ class TestFaucet(EthTesterCase):
         self.assertEqual(amount, 1024)
 
 
+    def test_signatures(self):
+        snake = Faucet(self.chain_spec).signature_for('give_to')
+        camel = Faucet(self.chain_spec).signature_for('giveTo')
+        self.assertEqual(snake, camel)
+        method = Faucet(self.chain_spec).method_for(snake)
+        self.assertEqual(method, 'give_to')
+        hx = snake.hex().ljust(64+8, 'f')
+        method = Faucet(self.chain_spec).method_for(hx)
+        self.assertEqual(method, 'give_to')
+
 if __name__ == '__main__':
     unittest.main()