##### Brief description

This interface is used by the client APP to send firmware files to the electronic price tag. After receiving the firmware file, the electronic price tag will perform the firmware upgrade task

##### Request URL

Interface address (case must be consistent)

- `http://192.168.1.x/upgrade`

##### Request method

- POST

##### Request message example

```http
POST /upgrade?file_path=files/upgrade/update.pkg 
Request Headers
Accept: */*
Host: 192.168.1.x
Accept-Encoding: gzip, deflate, br
Connection: keep-alive

Request Body
binary src: "/Users/happy/Downloads/update.pkg"
```

##### Parameters

| Parameter Name | Required | Type | Example | Description |
| --- | --- | --- | --- | --- |
| `file_path` | Yes | string | `files/upgrade/update.pkg` | fixed |

##### Request message example

```http
HTTP/1.1 200 OK
Content-Length: 47
Content-Type: application/json; charset=utf-8
```

##### Example of returning content

```json
{"STATE": "SUCCEED", "message": "File received"}
{"STATE": "ERROR", "message": "Not enough space"}
```

##### Return content field description

| Parameter Name | Type | Example | Description |
| --- | --- | --- | --- |
| `STATE` | string | SUCCEED / ERROR | Business status |
| `message` | string | File received / Not enough space | Status Description |