##### Brief description

- Device registration interface, used to obtain information such as MQTT server address, username, password, etc.

##### Request URL

Demo address

- `http://demo.esltag.cc/openapi/mqttregister`

##### Request method

- POST

##### Request Message Example

```http
POST http://demo.esltag.cc/openapi/mqttregister HTTP/1.1
Host: demo.esltag.cc
Accept: */*
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
```

##### Request Body Parameters

| Parameter name | Required | Type | Example | Description |
| --- | --- | --- | --- | --- |
| `appid` | Yes | string | `d114c07a-24ed-41b2-9cc3-58ae5bb9ace1_2303065600000005` | Account AppID |
| `sn` | Yes | string | 2C0547E35BA5 | Price Tag serial number |
| `ts` | Yes | long | 1679539549647 | Current timestamp is at 13 bits |
| `sign` | Yes | string | F26289DD0F88E121D0180B5D9C85980B | The signature value is calculated by the signature algorithm |

##### Response Message Example

```http
HTTP/1.1 200 OK
Content-Length: 121
Content-Type: application/json; charset=utf-8
```

##### Return an example

```json
{
    "State": "Done",
    "Message": "注册成功",
    "Number": "",
    "Data": {
        "mqtthost": "demo.esltag.cc",
        "mqttport": "1883",
        "username": "Signature|LTAI5tKZJbbwHxE********|**********",
        "password": "TAw321G60ExFcNCngsWY********",
        "client_id": "GID_test@@@2C0547C36***",
        "topic": "test/p2p/GID_test@@@2C0547C36***"
    },
    "Level": 0,
    "ErrorColumn": null
}
```

##### Return parameter description

###### Public parameters

| Parameter name | Type | Explain |
| --- | --- | --- |
| `State` | string | Return to the status code, Done / Fail |
| `Message` | string | Return information |
| `Number` | string | Error code |
| `Data` | string | json |

###### Data Parameter

| Parameter name | Type | Explain |
| --- | --- | --- |
| `mqtthost` | string | Mqtt Server Address |
| `mqttport` | string | Mqtt Server Port |
| `username` | string | User Name |
| `password` | string | Password |
| `client_id` | string | Mqtt client id |
| `topic` | string | Topic |

##### Remarks

- The return error code is not defined in this article, but can be defined as needed