1. Check merchant wallet balance
`interface address：{host}/api/v2/merch/walletBalance `interface address：GET/POST form
| field | type | nickname | description |
|---|---|---|---|
| merchId | Integer | merchant ID | |
| body | String | encryption parameter | See Table 4 for details |
| t | Integer | current timestamp | |
| key | String | sign | Md5(merchId+body+t+md5key) |
parameters： Table 9：
| field | type | nickname | description |
|---|---|---|---|
| merchName | String | Merchant account | Merchant backend login account |
body generation rules：
`1. base64Decode public key `2. Convert the parameters in Table 9 to jsonString
3. Use public key to encrypt jsonString with RSA (ECB mode, OAEP SHA256 pair, MGF1 padding)
4. The encryption result base64 Encode is the string body
Interface Response Results：
| field | type | nickname | description |
|---|---|---|---|
| code | Integer | status code | 0 means the request is normal, see the attached table for details. |
| message | String | message | |
| data | Return data | Merchant balance |