Add max_quantity to contract

Author: cpacia

api/restapi.py

@@ -550,7 +550,8 @@ def set_contract(self, request):
             else:
                 c = Contract(self.db, testnet=self.protocol.testnet)
             c.create(
-                str_to_bool(request.args["pinned"][0]),
+                str_to_bool(request.args["pinned"][0]) if "pinned" in request.args else False,
+                int(request.args["max_quantity"][0]) if "max_quantity" in request.args else 999999,
                 str(request.args["expiration_date"][0]),
                 request.args["metadata_category"][0],
                 request.args["title"][0].decode("utf8"),

market/contracts.py

@@ -95,6 +95,7 @@ def __init__(self, database, contract=None, hash_value=None, testnet=False):
 
     def create(self,
                pinned,
+               max_quantity,
                expiration_date,
                metadata_category,
                title,
@@ -152,7 +153,8 @@ def create(self,
                             "category": metadata_category.lower(),
                             "category_sub": "fixed price",
                             "last_modified": int(time.time()),
-                            "pinned": pinned
+                            "pinned": pinned,
+                            "max_quantity": max_quantity
                         },
                         "id": {
                             "guid": self.keychain.guid.encode("hex"),
@@ -299,6 +301,10 @@ def add_purchase_info(self,
         except AssertionError:
             raise Exception("Invalid Bitcoin address")
 
+        if "max_quantity" in self.contract["vendor_offer"]["listing"]["metadata"]:
+            if quantity > int(self.contract["vendor_offer"]["listing"]["metadata"]["max_quantity"]):
+                raise Exception("Quantity exceeds max quantity in listing")
+
         profile = Profile(self.db).get()
         order_json = {
             "buyer_order": {
@@ -1182,8 +1188,13 @@ def verify(self, sender_key):
             if not valid:
                 raise Exception("Invalid Bitcoin signature")
 
-            # verify buyer included the correct bitcoin amount for payment
+            # verify the quantity does not exceed the max
             quantity = int(self.contract["buyer_order"]["order"]["quantity"])
+            if "max_quantity" in self.contract["vendor_offer"]["listing"]["metadata"]:
+                if quantity > int(self.contract["vendor_offer"]["listing"]["metadata"]["max_quantity"]):
+                    raise Exception("Buyer tried to purchase more than the max quantity")
+
+            # verify buyer included the correct bitcoin amount for payment
             price_json = self.contract["vendor_offer"]["listing"]["item"]["price_per_unit"]
             if "bitcoin" in price_json:
                 asking_price = float(price_json["bitcoin"]) * quantity