Airswap improvement

pyexchange/airswap.py

@@ -18,12 +18,14 @@
 import logging
 import time
 import json
+import random
 
 from pprint import pformat
 from typing import Optional, List
 
 import requests
 
+from pymaker import Address
 from pymaker.util import hexstring_to_bytes, http_response_summary
 from web3 import Web3
 
@@ -43,13 +45,51 @@ def __init__(self, api_server: str, timeout: float):
         self.api_server = api_server
         self.timeout = timeout
 
-    def set_intents(self, maker_token_address, taker_token_address):
-        intents = self._build_intents(maker_token_address, taker_token_address)
+    def set_intents(self, buy_token: Address, sell_token: Address):
+        assert(isinstance(buy_token, Address))
+        assert(isinstance(sell_token, Address))
+
+        intents = self._build_intents(buy_token.__str__(), sell_token.__str__())
         return self._http_post(f"/setIntents", intents)
 
-    def sign_order(self, order):
+    def sign_order(self,
+                   maker_address,
+                   maker_token,
+                   maker_amount,
+                   taker_address,
+                   taker_token,
+                   taker_amount):
+
+        order = self._build_order(maker_address,
+                                  maker_token,
+                                  maker_amount,
+                                  taker_address,
+                                  taker_token,
+                                  taker_amount)
+
         return self._http_post(f"/signOrder", order)
 
+
+    def approve(self, buy_token: Address, sell_token: Address):
+        assert(isinstance(buy_token, Address))
+        assert(isinstance(sell_token, Address))
+
+        try:
+            buy_token_data = self._build_approve(buy_token.__str__())
+            sell_token_data = self._build_approve(sell_token.__str__())
+
+            self._http_post(f"/approveTokenForTrade", buy_token_data)
+            self._http_post(f"/approveTokenForTrade", sell_token_data)
+            logging.getLogger().info(f"token approval success: {buy_token.__str__()}, {sell_token.__str__()}")
+            return 'ok'
+
+        except Exception as e:
+             logging.getLogger().exception(f"Encountered an error when attempting to approve tokens with Airswap contract({e}).")
+
+
+    def _build_approve(self, token):
+        return {"tokenContractAddr": token}
+
     def _result(self, result) -> Optional[dict]:
         if not result.ok:
             raise Exception(f"Airswap API invalid HTTP response: {http_response_summary(result)}")
@@ -80,3 +120,28 @@ def _build_intents(self, maker_token_address, taker_token_address):
                 "takerToken": maker_token_address,
                 "role": "maker"
             }]
+
+    def _build_order(self,
+                     maker_address,
+                     maker_token,
+                     maker_amount,
+                     taker_address,
+                     taker_token,
+                     taker_amount):
+
+        # Set 5-minute expiration on this order
+        expiration = str(int(time.time()) + 300)
+        nonce = random.randint(0, 99999)
+
+        new_order = {
+            "makerAddress": maker_address,
+            "makerToken": maker_token,
+            "makerAmount": maker_amount,
+            "takerAddress": taker_address,
+            "takerToken": taker_token,
+            "takerAmount": taker_amount,
+            "expiration": expiration,
+            "nonce": nonce
+        }
+
+        return new_order