应用侧可以自行实现设备数据查询接口，以下使用python脚本演示设备数据查询过程,开发者可参考一下思路使用JAVA、nodejs等其他语言实现。

业务应用实现设备数据查询参考如下流程：

1. 调用设备管理平台的openapi获得设备列表

2. 选择指定设备获取设备详情信息及产品productKey

3. 使用productKey查询设备物模型并缓存在程序中

4. 使用物模型中定义的设备属性，生成查询条件

5. 调用TSDB接口查询设备数据

调用设备管理接口python3示例

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
'''
本示例代码演示如何通过api接口获取物联网平台的各项数据

'''

import json
import requests
import hashlib
import hmac
import urllib
import time
import string
import datetime
from AIoTbce.auth.bce_v1_signer import sign
from baidubce.auth.bce_credentials import BceCredentials
from baidubce import utils

AUTHORIZATION = "authorization"
BCE_PREFIX = "x-bce-"
DEFAULT_ENCODING = 'UTF-8'

# POC
AK = "c590c33583------e9a6d9fef6fe26"
SK = "f2b0452cc5------5788f484617dc0c"

# 请求物联网平台openapi接口签名
def do_sign(params):
    # 1.AK/SK、host、method、URL绝对路径、querystring

    host = params["host"]
    method = params["method"]
    query = params["query"]
    URI = params["URI"]

    # 2.x-bce-date
    x_bce_date = time.gmtime()
    x_bce_date = time.strftime('%Y-%m-%dT%H:%M:%SZ', x_bce_date)
    # 3.header和signedHeaders
    header = {
        "Host": host,
        "content-type": "application/json;charset=utf-8",
        "x-bce-date": x_bce_date
    }
    signedHeaders = "content-type;host;x-bce-date"
    # 4.认证字符串前缀
    authStringPrefix = "bce-auth-v1" + "/" + AK + "/" + x_bce_date + "/" + "1800"
    # 5.生成CanonicalRequest
    # 5.1生成CanonicalURI
    # windows下为urllib.parse.quote，Linux下为urllib.quote
    CanonicalURI = urllib.parse.quote(URI)
    # 5.2生成CanonicalQueryString
    CanonicalQueryString = utils.get_canonical_querystring(
        query, True).decode('utf-8')  # 如果您调用的接口的query比较复杂的话，需要做额外处理
    # 5.3生成CanonicalHeaders
    result = []
    for key, value in header.items():
        tempStr = str(urllib.parse.quote(key.lower(), safe="")) + \
            ":" + str(urllib.parse.quote(value, safe=""))
        result.append(tempStr)
    result.sort()
    CanonicalHeaders = "\n".join(result)
    # 5.4拼接得到CanonicalRequest
    CanonicalRequest = method + "\n" + CanonicalURI + \
        "\n" + CanonicalQueryString + "\n" + CanonicalHeaders
    # 6.生成signingKey
    signingKey = hmac.new(SK.encode('utf-8'),
                          authStringPrefix.encode('utf-8'), hashlib.sha256)
    # 7.生成Signature
    Signature = hmac.new((signingKey.hexdigest()).encode(
        'utf-8'), CanonicalRequest.encode('utf-8'), hashlib.sha256)
    # 8.生成Authorization并放到header里
    header['Authorization'] = authStringPrefix + "/" + \
        signedHeaders + "/" + Signature.hexdigest()
    # 9.发送API请求并接受响应
    url = "http://"+host + URI
    # print('ready rq==============', url, header)

    return [url, method, query, header, params]


def doreq(params):
    sign_info = do_sign(params)
    if sign_info[1] == 'GET':
        r = requests.get(
            sign_info[0], params=sign_info[2], headers=sign_info[3], verify=False)
    elif sign_info[1] == 'POST':
        r = requests.post(sign_info[0], headers=sign_info[3],
                          data=json.dumps(sign_info[4]), verify=False)
    else:
        return
    print(r)
    # print(r.text)

    res = json.loads(r.text)
    # print(res)

    # for device in res['result'] :
    #     print('--------------------------------------')
    #     print(device)

    # 日志文件
    file = "log.txt"

    with open(file, 'a+') as f:
        f.write(r.text+'\n')  # 加\n换行显示

    return res


if __name__ == "__main__":
    start = time.time()
    # 物联网平台实例ID
    instanceId = 'bsx110sdsfb5ihc8'
    # 调用设备获取设备列表
    body = {}
    query = {
        "pageNo": 1,
        "pageSize": 50
    }
    params = {
        "host": "180.76.236.1:8371",
        "method": "GET",
        "URI": "/v1/devices/"+instanceId,
        "query": query,
        "body": body
    }

    deviceList = doreq(params)
    print(deviceList)
    print('-----------------------------------------------------------------')
    
    # 调用获取设备物模型详情（示例中选取了第一个设备）
    productKey = deviceList['result'][0]['productKey']
    body = {}
    query = {}
    params = {
        "host": "180.76.236.1:8371",
        "method": "POST",
        "URI": f"/v1/products/{instanceId}/{productKey}/features/detail",
        "query": query,
        "body": body
    }

    features = doreq(params)
    print(features)

    for property in features['properties']:
        print(property)
        print(features['properties'][property])
        print('-----------------------------------------------------------------')

    print("耗时===========================", time.time()-start)

调用TSDB数据查询接口查询设备历史数据python3示例

根据设备管理接口返回的设备属性列表查询设备数据

import AIoTbce.protocol
from baidubce.bce_client_configuration import BceClientConfiguration
from baidubce.auth.bce_credentials import BceCredentials
from baidubce.services.tsdb.tsdb_client import TsdbClient
import time
import datetime
import json
# when use https as the protocol, you may find certificate expire problem, this can be resovled by adding the following lines
# import ssl
# ssl._create_default_https_context = ssl._create_unverified_context



def change_type(byte):
    if isinstance(byte, bytes):
        return str(byte, encoding="utf-8")
    return json.JSONEncoder.default(byte)


##########必填配置#############
# 用户的时序数据库域名，形式如databasename.tsdb.iot.gz.baidubce.com
HOST = 'iotxxxxx021.tsdb-max8bnu8nywt.tsdb.iot.gz.baidubce.com'
AK = '989962xxxxx38ef2ee457b28fe3e'     # 用户 Access Key ID
SK = '4939c4xxxxx4ef3b9723d32ac3854c8'     # 用户 Secret Access Key

###########可选配置#############
# 使用HTTP协议
protocol = baidubce.protocol.HTTP
# 使用HTTPS协议
# protocol= baidubce.protocol.HTTPS
connection_timeout_in_mills = None  # 连接超时时间
send_buf_size = None  # 发送缓冲区大小
recv_buf_size = None  # 接收缓冲区大小
retry_policy = None  # 重试策略

# 生成config对象
config = BceClientConfiguration(
    credentials=BceCredentials(AK, SK),
    endpoint=HOST,
    protocol=protocol,
    connection_timeout_in_mills=connection_timeout_in_mills,
    send_buf_size=send_buf_size,
    recv_buf_size=recv_buf_size,
    retry_policy=retry_policy)

# 创建TsdbCient
tsdb_client = TsdbClient(config)

# 查询单个属性记录
curtime = int(round(time.time() * 1000))
query_list = [{
    "metric": "pocdemo",
    "field": "temperature", # 属性标识
    "filters": {
        "start": curtime-24*60*60*1000, # 开始时间
        "end": curtime, # 截止时间
        "tags": {
            "deviceName": ["ht001"], # 设备标识
            "productKey":["dht22"] # 产品标识
        },
        "value": ">= 0"
    },
    "limit": 1000
}]
result = tsdb_client.get_datapoints(query_list)
print(result.results)
print('-----------------------------------------------------------------')

# 查询设备多个属性记录
query_list = [{
    "metric": "pocdemo",
    "fields": ["temperature", "humidity", "location"],  # 多个属性标识
    "filters": {
        "start": curtime-24*60*60*1000, # 开始时间
        "end": curtime, # 截止时间
        "tags": {
            "deviceName": ["ht001"], # 设备标识
            "productKey":["dht22"], # 产品标识
            "type":["property"] # 属性标识
        }
    },
    "limit": 1000
}]
result = tsdb_client.get_datapoints(query_list)
print(result.results)
# print(json.dumps(result.results, ensure_ascii=False))
print('-----------------------------------------------------------------')

# 查询设备最后一次上报状态
query_list = [{
    "metric": "pocdemo",
    "fields": ["temperature", "humidity", "location", "last_time"],  # 查询多个域
    "filters": {
        "start": 1597507200000, # 最后一次上报消息的时间戳（固定值）
        "end": 1597507200000,
        "tags": {
            "deviceName": ["ht001"],
            "productKey":["dht22"],
            "type":["last_state"] # 最后一次上报消息标识
        }
    },
    "limit": 1000
}]
result = tsdb_client.get_datapoints(query_list)
print(type(result.results))
print(result.results[0])
res = result.results[0]
print(type(res))
data = {
    'timestamp':0,
    'properties':{}
}
for field in range(0,len(res.fields)):
    if res.fields[field] == 'last_time' :
        data['timestamp'] = res.groups[0].values[0][field+1]
    else :
        data['properties'][res.fields[field]] = res.groups[0].values[0][field+1]
    # print(res.fields[field])
    # print(res.groups[0].values[0][field+1])
    print(data)
    print('---------')