Bittrex REST API for Python, I want to create an order using API v3 https://api.bittrex.com/v3/orders - python-2.7

Question

I need help to create orders using the bittrex version 3 REST API. I have the code below and I can't understand what is missing to work.
I can make other GET calls, but I cannot make this POST request.
I don't know how to deal with the passing of parameters.
Official documentation at https://bittrex.github.io/api/v3#tag-Orders.
def NewOrder(market, amount, price):
#print 'open sell v3', market
market = 'HEDG-BTC'#'BTC-'+market
uri = 'https://api.bittrex.com/v3/orders?'
params = {
'marketSymbol': 'BTC-HEDG',#'HEDG-BTC', #market
'direction': 'BUY',
'type': 'LIMIT',
'quantity': amount,
'limit': price,
'timeInForce': 'POST_ONLY_GOOD_TIL_CANCELLED',
'useAwards': True
}
timestamp = str(int(time.time()*1000))
Content = ""
contentHash = hashlib.sha512(Content.encode()).hexdigest()
Method = 'POST'
uri2 = buildURI(uri, params)
#uri2 = 'https://api.bittrex.com/v3/orders?direction=BUY&limit=0.00021&marketSymbol=HEDG-BTC&quantity=1.1&timeInForce=POST_ONLY_GOOD_TIL_CANCELLED&type=LIMIT&useAwards=True'
#print uri2
PreSign = timestamp + uri2 + Method + contentHash# + subaccountId
#print PreSign
Signature = hmac.new(apisecret, PreSign.encode(), hashlib.sha512).hexdigest()
headers = {
'Api-Key' : apikey,
'Api-Timestamp' : timestamp,
'Api-Content-Hash': contentHash,
'Api-Signature' : Signature
}
r = requests.post(uri2, data={}, headers=headers, timeout=11)
return json.loads(r.content)
NewOrder('HEDG', 1.1, 0.00021)
And my error message:
{u'code': u'BAD_REQUEST', u'data': {u'invalidRequestParameter': u'direction'}, u'detail': u'Refer to the data field for specific field validation failures.'}

Answer 1

It seems from the documentation that this body is expected by the api as json data:
{
"marketSymbol": "string",
"direction": "string",
"type": "string",
"quantity": "number (double)",
"ceiling": "number (double)",
"limit": "number (double)",
"timeInForce": "string",
"clientOrderId": "string (uuid)",
"useAwards": "boolean"
}
and you are setting these values as url params that's the issue.
you need to do this:
uri = 'https://api.bittrex.com/v3/orders'
# NOTE >>>> please check that you provide all the required fields.
payload = {
'marketSymbol': 'BTC-HEDG',#'HEDG-BTC', #market
'direction': 'BUY',
'type': 'LIMIT',
'quantity': amount,
'limit': price,
'timeInForce': 'POST_ONLY_GOOD_TIL_CANCELLED',
'useAwards': True
}
# do rest of the stuffs as you are doing
# post payload as json data with the url given in doc
r = requests.post(uri, json=payload, headers=headers, timeout=11)
print(r.json())
If you still have issues let us know. If it works then please mark answer as accepted.
Hope this helps.

Answer 2

I made the following modifications to the code but started to give error in 'Content-Hash'
I'm assuming that some parameters are optional so they are commented.
def NewOrder(market, amount, price):
market = 'BTC-'+market
uri = 'https://api.bittrex.com/v3/orders'
payload = {
'marketSymbol': market,
'direction': 'BUY',
'type': 'LIMIT',
'quantity': amount,
#"ceiling": "number (double)",
'limit': price,
'timeInForce': 'POST_ONLY_GOOD_TIL_CANCELLED',
#"clientOrderId": "string (uuid)",
'useAwards': True
}
#ceiling (optional, must be included for ceiling orders and excluded for non-ceiling orders)
#clientOrderId (optional) client-provided identifier for advanced order tracking
timestamp = str(int(time.time()*1000))
Content = ''+json.dumps(payload, separators=(',',':'))
print Content
contentHash = hashlib.sha512(Content.encode()).hexdigest()
Method = 'POST'
#uri2 = buildURI(uri, payload)#line not used
print uri
#PreSign = timestamp + uri2 + Method + contentHash# + subaccountId
PreSign = timestamp + uri + Method + contentHash# + subaccountId
print PreSign
Signature = hmac.new(apisecret, PreSign.encode(), hashlib.sha512).hexdigest()
headers = {
'Api-Key' : apikey,
'Api-Timestamp' : timestamp,
'Api-Content-Hash': contentHash,
'Api-Signature' : Signature
}
r = requests.post(uri, json=payload, headers=headers, timeout=11)
print(r.json())
return json.loads(r.content)
NewOrder('HEDG', 1.5, 0.00021)
{u'code': u'INVALID_CONTENT_HASH'}

Answer 3

Bittrex API via requests package PYTHON
import hmac
import hashlib
import time, requests
nonce = str(int(time.time() * 1000))
content_hash = hashlib.sha512(''.encode()).hexdigest()
signature = hmac.new(
'<SECRET_KEY>'.encode(),
''.join([nonce, url, 'GET', content_hash]).encode(),
hashlib.sha512
).hexdigest()
headers = {
'Api-Timestamp': nonce,
'Api-Key': '<API_KEY>',
'Content-Type': 'application/json',
'Api-Content-Hash': content_hash,
'Api-Signature': signature
}
result = requests.get(url=url, headers=headers)