script to withdraw exact amount of tokens

erc20/bridge/token/token_exact_withdraw.py

@@ -0,0 +1,74 @@
+#!/opt/anaconda3/bin/python
+
+from web3 import Web3
+from web3.utils.transactions import wait_for_transaction_receipt
+import json
+from toml import load
+import sys
+from random import randint
+
+_tokenName = 'BridgeableToken'
+_abiFile = _tokenName+".abi"
+
+test_env_db = '/home/koal/parity/bridge/test_env_db.toml'
+try:
+    test_env = load(test_env_db)
+except:
+    sys.exit(1)
+
+bridge_config = load(test_env['bridge_config'])
+bridge_db     = load(test_env['bridge_db'])
+
+_IPC_file = bridge_config['foreign']['ipc']
+web3 = Web3(Web3.IPCProvider(_IPC_file))
+
+_gasPrice    = bridge_config['transactions']['withdraw_confirm']['gas_price']
+
+tokenContractAddress = web3.toChecksumAddress(test_env['token_contract_address'])
+
+bridgeContractAddress = web3.toChecksumAddress(bridge_db['foreign_contract_address'])
+
+if 'actor_address' in test_env:
+    actor = web3.toChecksumAddress(test_env['actor_address'])
+else:
+    sys.exit("actor is not set in testenv DB")
+
+#----------------------------------------------------------------------------
+# Read ABI
+#----------------------------------------------------------------------------
+with open(_abiFile) as f:
+    _contractABI=json.load(f)
+f.close()
+#print(_contractABI[0])
+
+ContractFactory = web3.eth.contract(
+    abi = _contractABI,
+)
+
+if (len(sys.argv) == 2):
+    value = int(sys.argv[1])
+else:
+    sys.exit(1)
+
+#############################################################################
+# MAIN PART STARTED HERE
+#############################################################################
+
+TokenContract = ContractFactory(tokenContractAddress)
+
+print("Withdraw", value, "from Foreign bridge")
+
+txTmpl = {'from': actor, 
+          'gasPrice': _gasPrice}
+
+txToSend = TokenContract.functions.approveAndCall(bridgeContractAddress, value, b'').buildTransaction(txTmpl)
+
+# This is needed since sendTransaction does not expect this argument parameter and does not skip it by some reason 
+txToSend.pop('chainId', None)
+
+txHash = web3.personal.sendTransaction(txToSend, "11")
+wait_for_transaction_receipt(web3, txHash)
+
+print("TX:", txHash.hex())
+
+sys.exit(0)