Interface Description：
- Place Contract Order
Request URL：
https://apiv2.bitz.com/Contract/addContractTrade
Request Mode：
POST
Parameter：
| Parameter | Required | Type | Comment |
|---|---|---|---|
| apiKey | true | string | User-applied apiKey |
| timeStamp | true | string | Current timestamp |
| nonce | true | string | Random 6-character string |
| sign | true | string | signature for requesting parameters |
| contractId | true | int | Contract ID |
| price | false | float | Price，if type is market，delivery of Price is not required. |
| amount | true | int | Amount |
| leverage | true | float | Leverage |
| direction | true | int | Direction 1: long；-1: short |
| type | true | string | Type limit: limit order; market: market order, lowercase string required |
| isCross | true | int | Cross Margin or not 1: Cross Margin，-1：Isolated Margin |
How to sign for required parameter：
All parameters submitted by users except sign require signature.
First, sort signature strings in alphabetical order based on parameters (compare the first letter of all parameter, if they differ, then the string whose first letter comes earlier in the alphabet comes before the other string. If the first letters are the same, then the second letters are compared, and so on).
For example：Sign for the following parameter
apiKey=376892265asdad5d12726d8bbfbd8912b3&timeStamp=1510235730&nonce=309127&contractId=101&price=1&amount=1&leverage=10&direction=1&type=limit&isCross=1 and add application secretKey (only needs value, parameter and ‘&” is not required.)
For example:
secretKey=aQmE8U7bxj16KdJcSd3yX8F8Sakd8aO6LopnHXh27d4kWyb28PxcaTvGrajLDvAw
Signature string after splicing: apiKey=376892265asdad5d12726d8bbfbd8912b3&timeStamp=1510235730&nonce=309127&contractId=101&price=1&amount=1&leverage=10&direction=1&type=limit&isCross=1aQmE8U7bxj16KdJcSd3yX8F8Sakd8aO6LopnHXh27d4kWyb28PxcaTvGrajLDvAw
Note，"sign" is a required parameter.
Last，use md5 32bit algorithm to apply signature algorithm to the parameter, and then generate final signature string (the string assigns value to parameter ‘sign’).
Example of Return Result：
{
"status":200,
"msg":"",
"data":{
"orderId":710370//Order ID
},
"time":1533035297,
"microtime":"0.41892000 1533035297",
"source":"api"
}