add custom exception for online lookup

expose timeout/proxies arguments for the online lookup ignore missing signatures in abi.json fix example version bump
tintinweb · Jul 4, 2018 · aa96623 · aa96623
1 parent 20783ba
commit aa96623
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Showing 4 changed files with 39 additions and 18 deletions.
diff --git a/ethereum_input_decoder/__main__.py b/ethereum_input_decoder/__main__.py
@@ -1,9 +1,11 @@
 # -*- coding: UTF-8 -*-
 
-from ethereum_input_decoder import ContractAbi,AbiMethod, Utils
+import sys
+import os
 import argparse
 import json
-import sys, os
+from ethereum_input_decoder import ContractAbi,AbiMethod, Utils
+
 
 def main():
     parser = argparse.ArgumentParser(description='Ethereum Input decoder')
@@ -58,4 +60,4 @@ def main():
 
 
 if __name__ == '__main__':
-    main()
+    main()
diff --git a/ethereum_input_decoder/decoder.py b/ethereum_input_decoder/decoder.py
@@ -8,6 +8,18 @@
 import requests
 
 
+class InputDecoderException(Exception):
+    pass
+
+
+class FourByteDirectoryException(InputDecoderException):
+    pass
+
+
+class FourByteDirectoryOnlineLookupError(FourByteDirectoryException):
+    pass
+
+
 class Utils:
 
     @staticmethod
@@ -38,28 +50,32 @@ def parse_text_signature(text_signature):
                 'outputs': []}
 
     @staticmethod
-    def lookup_signatures(sighash):
-        resp = requests.get("https://www.4byte.directory/api/v1/signatures/?hex_signature=%s" % sighash).json()
-        for sig in resp["results"]:
-            yield sig["text_signature"]
+    def lookup_signatures(sighash, timeout=None, proxies=None):
+        try:
+            resp = requests.get("https://www.4byte.directory/api/v1/signatures/?hex_signature=%s" % sighash,
+                                timeout=timeout, proxies=proxies).json()
+            for sig in resp["results"]:
+                yield sig["text_signature"]
+        except (requests.exceptions.RequestException) as re:
+            raise FourByteDirectoryOnlineLookupError(re)
 
     @staticmethod
-    def get_pseudo_abi_for_sighash(sighash):
-        for text_signature in FourByteDirectory.lookup_signatures(sighash):
+    def get_pseudo_abi_for_sighash(sighash, timeout=None, proxies=None):
+        for text_signature in FourByteDirectory.lookup_signatures(sighash, timeout=timeout, proxies=proxies):
             pseudo_abi = FourByteDirectory.parse_text_signature(text_signature)
             pseudo_abi['signature'] = sighash
             yield pseudo_abi
 
     @staticmethod
-    def get_pseudo_abi_for_input(s):
+    def get_pseudo_abi_for_input(s, timeout=None, proxies=None):
         """
         Lookup sighash from 4bytes.directory, create a pseudo api and try to decode it with the parsed abi.
         May return multiple results as sighashes may collide.
         :param s: bytes input
         :return: pseudo abi for method
         """
         sighash = Utils.bytes_to_str(s[:4])
-        for pseudo_abi in FourByteDirectory.get_pseudo_abi_for_sighash(sighash):
+        for pseudo_abi in FourByteDirectory.get_pseudo_abi_for_sighash(sighash, timeout=timeout, proxies=proxies):
             types = [ti["type"] for ti in pseudo_abi['inputs']]
             try:
                 # test decoding
@@ -98,7 +114,10 @@ def _prepare_abi(self, jsonabi):
                 abi_e.setdefault("inputs", [])
                 self.signatures[b"__fallback__"] = abi_e
             elif abi_e["type"] == "function":
-                self.signatures[Utils.str_to_bytes(abi_e["signature"])] = abi_e
+                # function and signature present
+                # todo: we could generate the sighash ourselves? requires keccak256
+                if abi_e.get("signature"):
+                    self.signatures[Utils.str_to_bytes(abi_e["signature"])] = abi_e
             elif abi_e["type"] == "event":
                 self.signatures[b"__event__"] = abi_e
             else:

diff --git a/setup.py b/setup.py
@@ -9,7 +9,7 @@ def read(fname):
 
 setup(
     name="ethereum_input_decoder",
-    version="0.2.1",
+    version="0.2.2",
     packages=["ethereum_input_decoder"],
     author="tintinweb",
     author_email="tintinweb@oststrom.com",
@@ -18,7 +18,7 @@ def read(fname):
     license="GPLv3",
     keywords=["ethereum", "blockchain", "input", "transaction", "decoder"],
     url="https://github.com/tintinweb/ethereum-input-decoder/",
-    download_url="https://github.com/tintinweb/ethereum-input-decoder/tarball/v0.2.1",
+    download_url="https://github.com/tintinweb/ethereum-input-decoder/tarball/v0.2.2",
     #python setup.py register -r https://testpypi.python.org/pypi
     long_description=read("README.rst") if os.path.isfile("README.rst") else read("README.md"),
     install_requires=["eth-abi", "requests"],

diff --git a/test/example.py b/test/example.py
@@ -1,4 +1,4 @@
-from ethereum_input_decoder import ContractAbi
+from ethereum_input_decoder import ContractAbi, Utils
 import json
 
 if __name__ == "__main__":
@@ -11,13 +11,13 @@
 
     # This is the constructor arguments:
     #   https://etherscan.io/address/0xab7c74abc0c4d48d1bdad5dcb26153fc8780f83e#code
-    print(ca.describe_constructor(ContractAbi.str_to_bytes(
+    print(ca.describe_constructor(Utils.str_to_bytes(
         "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")))
     # constructor None ((address[]) _owners = ('0x2903cadbe271e057edef157340b52a5898d7424f', '0xba7ca1bcf210c1b37cf5818816c4a819c3040ea7', '0x14cd6536d449e3f6878f2d6859e1ff92ae0990e6', '0x0c24441e42277445e38e02dfc3494577c05ba46b'), (uint256) _required = 2, (uint256) _daylimit = 1000000000000000000) returns ()
 
 
     # This is one input transaction:
     #   https://www.etherchain.org/tx/1e9ed6236afb884fe7cad9a807886ba61b9e9a2fc944a991e3e8725d2158c7b2
-    print(ca.describe_input(ContractAbi.str_to_bytes(
-        "0x797af62798d790d3133e0049215669e09b55a0b59d586c95f94c2d56b2812040133d7707")))
+    print(ca.describe_input(Utils.str_to_bytes(
+        "0xfedd60920000000000000000000000000595d187cac88f04466371eff3a6b6d1b12fb013b92dd9476601c067bcd9730c83d54263fbc0da1c2c01f05a834199427aa3fad40000000000000000000000005c3766a9a906aa17e16dbbdaac0c93d41c0d057f")))
     # f