CEX API - LabMazurokCom/Blockchain GitHub Wiki

Intro

Website: https://cex.io/

Documentation: https://cex.io/rest-api

Limits: UNKNOWN.

Fee used in bot: 0.25% (taker for monthly volume less than 5 BTC).

Order book

https://cex.io/api/order_book/BTC/USD/?depth=50

If limit is omitted then all orders will be returned.

Response: JSON

{
  "timestamp": 1513173506,
  "bids": [
      [7572.3, 0.04],
      [7572.0, 2.401],
      ...
  ],
  "asks": [
      [7603.3, 2.08128],
      [7603.4, 0.3],
      ...
  ],
  "pair": "BTC:USD",
  "id": 158217212,
  "sell_total": "1299.73578729",
  "buy_total": "10006393.37"
}

Field	Type	Meaning
timestamp	number	UNIX timestamp
bids	[number]
asks	[number]
pair	string	Pair name symbol1:symbol2
id	integer	Incremental version id of order-book snapshot, may be used to check if order-book changed
sell_total	string	Total available in symbol1 (e.g. BTC)
buy_total	string	Total available in symbol2 (e.g. USD)

Ticker

https://cex.io/api/ticker/BTC/USD

Response: JSON

{
    'timestamp': '1523544161',
    'low': '6734',
    'high': '7950.8',
    'last': '7621.7',
    'volume': '1669.39889875',
    'volume30d': '36675.76574049',
    'bid': 7617.8,
    'ask': 7620.8
}

Order types

Limit order

A limit order is placed to buy or sell a pre-defined amount of cryptocurrency at a set price. Execution of this order type is not guaranteed until a price requested by the placing user can be matched with an opposite order from another user. Until full execution, the order may be canceled by the user at any time.

These orders may be partially completed if there is currently not sufficient volume at a matching price to cover the entire order. The remainder of the order will be left open until closed by another matching order. The remainder of the order may be canceled as well, returning the remainder to user's balance.

The executed part of a limit order may not be reversed or returned.

Market (immediate) order

Market order (instant order) involves buying or selling cryptocurrency immediately at the best available price. Selling with a market order is the same as Limit Order, except the best available price is used automatically. Market order is executed instantly in most cases (only a complete absence of orders in the order book will leave it hanging) and cannot be reversed.

Currency limits: https://cex.io/api/currency_limits

Private API request example

import requests
import hashlib
import hmac
import time

id='ID'
api_key='API_KEY'
api_secret=b'API_SECRET'

nonce = int(round(time.time() * 1000))

params = str(nonce) + id + api_key

params = bytes(params, encoding='utf-8')

H = hmac.new(api_secret, params, digestmod = hashlib.sha256)
sign = H.hexdigest().upper()

print(sign)
print(' ' + sign[1:-1] + ' ')
print(len(sign[1:-1]))

body = {
    "key": api_key,
    "signature": sign,
    "nonce": str(nonce)
}

endpoint = "https://cex.io/api/"
req = "balance/"

r = requests.post(endpoint + req, data=body)

print(r.text)

Place order

https://cex.io/api/place_order/{symbol1}/{symbol2}

Parameters

Position	Name	Type	Description
path	symbol1	string	The first currency code
path	symbol2	string	The second currency code
body	body	PlaceOrderRequest

Body example

{
  "key": "HLixH1aYdOIWOoRyoHkFpHlawrM",
  "signature": "0BDEDB9339DCE83D46F09A1527663762B52C8B12BCD1910E685BEAFEEABECFF9",
  "nonce": "1513175715",
  "type": "buy",
  "amount": 12,
  "price": 1155.67
}

Body parameters

Name	Type	Description
key	string	Your own API key. To get an API key, go to Account -> API Access Tab. Set permissions and click "Generate key".
signature	string	An HMAC-SHA256 encoded message containing - a nonce, user ID and API key. The HMAC-SHA256 code must be generated using a secret key that was generated with your API key. This code must be converted to its hexadecimal representation (64 uppercase characters).
nonce	string	The nonce is a regular integer number. It must be increasing with every request you make. Read more about it here. Example - if you set nonce to 1 in your first request, you must set it to at least 2 in your second request. You are not required to start with 1. A common practice is to use unix time for that parameter.
order_type	string	Probably not used. See example
type	string	Order type
amount	number	amount
price	string	price

Responses

Code 200: OK

Schema: ShortOrder (some fields omitted)

Name	Type	Description
id	string	order id
time	string	timestamp
type	string	Order type
price	string	price
amount	string	amount
pending	string	pending amount (if partially executed)
symbol1	string	Currency code
symbol2	string	Currency code
symbol1Amount	string
symbol2Amount	string

Examples

application/json

{
  "complete": false,
  "id": "89067468",
  "time": 1512054972480,
  "pending": "12.00000000",
  "amount": "12.00000000",
  "type": "buy",
  "price": "1155.67"
}

application/json, market order

{
  "symbol2Amount": "10000",
  "symbol1Amount": "19970000",
  "time": 1506615736816,
  "message": "Your order has been completed. Bought 0.19970000 BTC for 100.00 USD",
  "type": "buy",
  "id": "88640269"
}

Cancel order

https://cex.io/api/cancel_order/