:Python 例

スクリプトテンプレート

次の Python スクリプトテンプレートに基づいて、データ解析スクリプトを記述できます。

# Converts the custom data of devices to Alink protocol data. This function is called when devices report data to IoT Platform.
# Input: A rawData list. The list elements must be of the Int type and cannot be empty.
# Output: A jsonObj dictionary. It cannot be empty.
def raw_data_to_protocol(rawData):
    jsonObj = {}
    return jsonObj

# Converts Alink data to data formats that can be recognized by devices before data is sent to devices from IoT Platform.
# Input: A jsonData dictionary. It cannot be empty.
# Output: A rawData list. The list elements must be integers from 0 to 255. The list cannot be empty.
def protocol_to_raw_data(jsonData):
    rawData = []
    return rawData

追加の考慮事項

• グローバル変数を使用しないでください。 グローバル変数を使用すると、実行結果に不整合が生じる可能性があります。
• スクリプトでは、2 つの補数演算を使用してデータを処理します。 範囲 [-128,127] の値の補数は [0,255] です。 たとえば、-1 の補数は 10 進数の 255 です。
• raw_data_to_protocol 関数の入力は整数配列です。 ビット単位の AND 演算 には、0xFF を使用して補数を取得します。
• protocol_to_raw_data 関数は、IoT Platform から送信されたデータを解析し、結果を配列で返します。 配列要素は 0〜255 の整数です。

例

次のスクリプトは、「TSL データの解析例」で定義されているプロパティとプロトコルに基づいています 。

# coding=UTF-8
import struct

COMMAND_REPORT = 0x00 # Property data reported by devices
COMMAND_SET = 0x01 # Property setting command data from the cloud
COMMAND_REPORT_REPLY = 0x02 # // Response data for devices reporting properties
COMMAND_SET_REPLY = 0x03 # // Response data for setting device property command
COMMAD_UNKOWN = 0xff  # // Unknown commands
ALINK_PROP_REPORT_METHOD = 'thing.event.property.post' # The topic for devices to upload property data to the cloud
ALINK_PROP_SET_METHOD = 'thing.service.property.set' # // The topic for IoT platform to send property setting commands to control devices
ALINK_PROP_SET_REPLY_METHOD = 'thing.service.property.set' # // The topic for devices to report property setting results to IoT platform


# Example data:
# The device reports property data
# Input parameters->
#    0x000000000100320100000000
# Output result->
#    {"method":"thing.event.property.post","id":"1","params":{"prop_float":0,"prop_int16":50,"prop_bool":1},"version":"1.0"}
# The device responds after setting properties
# Input parameters->
#    0x0300223344c8
# Output result->
#    {"code":"200","data":{},"id":"2241348","version":"1.0"}

def raw_data_to_protocol(bytes):
    uint8Array = []
    for byteValue in bytes:
        uint8Array.append(byteValue & 0xff)

    fHead = uint8Array[0]
    jsonMap = {}
    if fHead == COMMAND_REPORT:
        jsonMap['method'] = ALINK_PROP_REPORT_METHOD
        jsonMap['version'] = '1.0'
        jsonMap['id'] = str(bytes_to_int(uint8Array[1:5]))
        params = {}
        params['prop_int16'] = bytes_to_int(uint8Array[5:7])
        params['prop_bool'] = bytes_to_int(uint8Array[7: 8])
        params['prop_float'] = bytes_to_int(uint8Array[8:])
        jsonMap['params'] = params
    elif fHead == COMMAND_SET_REPLY:
        jsonMap['version'] = '1.0'
        jsonMap['id'] = str(bytes_to_int(uint8Array[1:5]))
        jsonMap['code'] = str(bytes_to_int(uint8Array[5:]))
        jsonMap['data'] = {}

    return jsonMap


# Example data:
# IoT Platform pushes a command for setting properties to the device
# Input parameters->
#    {"method":"thing.service.property.set","id":"12345","version":"1.0",
#    "params":{"prop_float":123.452, "prop_int16":333, "prop_bool":1}}
# Output result->
#    0x0100003039014d0142f6e76d
# IoT Platform responds after the device reports properties
# Input data->
#    {"method":"thing.event.property.post","id":"12345","version":"1.0","code":200,"data":{}}
# Output result->
#    0x0200003039c8
def protocol_to_raw_data(json):
    method = json.get('method', None)
    id = json.get('id', None)
    version = json.get('version', None)
    payload_array = []

    if method == ALINK_PROP_SET_METHOD:
        params = json.get('params')
        prop_float = params.get('prop_float', None)
        prop_int16 = params.get('prop_int16', None)
        prop_bool = params.get('prop_bool', None)

        payload_array = payload_array + int_8_to_byte(COMMAND_SET)
        payload_array = payload_array + int_32_to_byte(int(id))
        payload_array = payload_array + int_16_to_byte(prop_int16)
        payload_array = payload_array + int_8_to_byte(prop_bool)
        payload_array = payload_array + float_to_byte(prop_float)

    elif method == ALINK_PROP_REPORT_METHOD:
        code = json.get('code', None)
        payload_array = payload_array + int_8_to_byte(COMMAND_REPORT_REPLY)
        payload_array = payload_array + int_32_to_byte(int(id))
        payload_array = payload_array + int_8_to_byte(code)
    else:
        code = json.get('code')
        payload_array = payload_array + int_8_to_byte(COMMAD_UNKOWN)
        payload_array = payload_array + int_32_to_byte(int(id))
        payload_array = payload_array + int_8_to_byte(code)

    return payload_array


# Converts a byte array to an integer type
def bytes_to_int(bytes):
    data = ['%02X' % i for i in bytes]
    return int(''.join(data), 16)


# Converts a byte array to a floating point without precision
def bytes_to_float(bytes):
    data = []
    for i in bytes:
        t_value = '%02X' % i
        if t_value % 2 ! = 0:
            t_value += 0
        data.append(t_value)
    hex_str = ''.join(data)
    return struct.unpack('! f', hex_str.decode('hex'))[0]


# Converts an 8-bit integer to a byte array
def int_8_to_byte(value):
    t_value = '%02X' % value
    if len(t_value) % 2 ! = 0:
        t_value += '0'

    return hex_string_to_byte_array(t_value)


# Converts a 32-bit integer to a byte array
def int_32_to_byte(value):
    t_value = '%08X' % value
    if len(t_value) % 2 ! = 0:
        t_value += '0'

    return hex_string_to_byte_array(t_value)


# Converts a 16-bit integer to a byte array
def int_16_to_byte(value):
    t_value = '%04X' % value
    if len(t_value) % 2 ! = 0:
        t_value += '0'

    return hex_string_to_byte_array(t_value)


# Converts a float into an integer array
def float_to_byte(param):
    return hex_string_to_byte_array(struct.pack(">f", param).encode('hex'))


# Converts a hexadecimal string to a byte array
def hex_string_to_byte_array(str_value):
    if len(str_value) % 2 ! = 0:
        return None

    cycle = len(str_value) / 2

    pos = 0
    result = []
    for i in range(0, cycle, 1):
        temp_str_value = str_value[pos:pos + 2]
        temp_int_value = int(temp_str_value, base=16)

        result.append(temp_int_value)
        pos += 2
    return result