0. 版本说明

本示例基于华为云Python SDK开发

1. 简介

基于华为云Python SDK, 与资产属性值的相关操作

2. 开发前准备

已注册华为云, 并完成实名认证; 已获取华为云账号对应的Access Key（AK）和Secret Access Key(SK); Python3及其以上版本

3. 安装SDK

                    
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pip install huaweicloudsdkiotanalytics

4. 开始使用

4.1 导入依赖模块

                    
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# 用户身份认证
from huaweicloudsdkcore.auth.credentials import BasicCredentials
# 请求异常类
from huaweicloudsdkcore.exceptions.exceptions import ServiceResponseException
# 导入相应产品的 {Service}Client
from huaweicloudsdkiotanalytics.v1.iotanalytics_client import IoTAnalyticsClient
# 导入待请求接口的类
from huaweicloudsdkcore.http.http_config import HttpConfig
from huaweicloudsdkiotanalytics.v1.model.dt_transform_metrics import DTTransformMetrics
from huaweicloudsdkiotanalytics.v1.model.get_metrics_value import GetMetricsValue
from huaweicloudsdkiotanalytics.v1.model.last_asset_property_value_request import LastAssetPropertyValueRequest
from huaweicloudsdkiotanalytics.v1.model.metric_input import MetricInput
from huaweicloudsdkiotanalytics.v1.model.raw_request import RawRequest
from huaweicloudsdkiotanalytics.v1.model.show_last_property_value_request import ShowLastPropertyValueRequest
from huaweicloudsdkiotanalytics.v1.model.show_metric_value_request import ShowMetricValueRequest
from huaweicloudsdkiotanalytics.v1.model.show_property_raw_value_request import ShowPropertyRawValueRequest
from huaweicloudsdkiotanalytics.v1.model.time_span_dt import TimeSpanDT
from huaweicloudsdkiotanalytics.v1.model.transform_metrics_request import TransformMetricsRequest
import os

4.2.1 配置客户端属性

                    
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config = HttpConfig.get_default_config()
config.ignore_ssl_verification = True
config.proxy_protocol = "http"

4.2.2 初始化认证信息

                    
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auth = BasicCredentials(
	ak=your_ak,
	sk=your_sk,
	project_id=project_id
)

4.2.3 初始化客户端

                    
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io_t_analytics_client = IoTAnalyticsClient.new_builder() \
	.with_http_config(config=config) \
	.with_credentials(credentials=auth) \
	.with_endpoint(endpoint=endpoint) \
	.build()

5. 示例代码

使用如下代码对资产属性值进行相关查询操作，调用前请根据实际情况替换如下变量： 通用参数： {your ak string}、{your sk string} , 以及各个方法中包含的参数。

                    
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package com.huawei.iotanalytics;

class PropertyValueApplication:

    def __init__(self):
        pass

    @staticmethod
    def main(args):
        # 认证用的ak和sk直接写到代码中有很大的安全风险，建议在配置文件或者环境变量中密文存放，使用时解密，确保安全；
        # 本示例以ak和sk保存在环境变量中来实现身份验证为例，运行本示例前请先在本地环境中设置环境变量HUAWEICLOUD_SDK_AK和HUAWEICLOUD_SDK_SK。
        ak = os.environ["HUAWEICLOUD_SDK_AK"]
        sk = os.environ["HUAWEICLOUD_SDK_SK"]
        endpoint = "{your endpoint string}"
        project_id = "{your project id}"
        # 配置客户端属性
        config = HttpConfig.get_default_config()
        # 根据需要配置是否跳过SSL证书验证
        config.ignore_ssl_verification = True
        config.proxy_protocol = "http"
        # 创建认证
        auth = BasicCredentials(
            ak=ak,
            sk=sk,
            project_id=project_id
        )
        # 创建IoTAnalyticsClient实例并初始化
        io_t_analytics_client = IoTAnalyticsClient.new_builder() \
            .with_http_config(config=config) \
            .with_credentials(credentials=auth) \
            .with_endpoint(endpoint=endpoint) \
            .build()
        # 通过SDK,调用获取资产属性最新值接口
        PropertyValueApplication.show_last_property_value(io_t_analytics_client)
        # 通过SDK,调用获取资产属性聚合值接口
        PropertyValueApplication.show_metric_value(io_t_analytics_client)
        # 通过SDK,获取资产属性历史值接口
        PropertyValueApplication.show_property_raw_value(io_t_analytics_client)

    @staticmethod
    def show_last_property_value(client):
        """
        获取资产属性最新值
        """
        try:
            show_last_property_value_request = ShowLastPropertyValueRequest()
            last_asset_property_value_request = LastAssetPropertyValueRequest()
            show_last_property_value_request.body = last_asset_property_value_request
            show_last_property_value_request.asset_id = "your assetId"
            show_last_property_value_response = client.show_last_property_value(show_last_property_value_request)
            # 输出json格式的字符串响应
            print(show_last_property_value_response)
        except ServiceResponseException as e:
            print("HttpStatusCode: "+e.status_code)
            print("RequestId: "+e.request_id)
            print("ErrorCode: "+e.error_code)
            print("ErrorMsg: "+e.error_msg)

    @staticmethod
    def show_metric_value(client):
        """
        获取资产属性聚合值
        """
        try:
            # 构造请求参数
            show_metric_value_request = PropertyValueApplication.__get_show_metric_value_request()
            show_metric_value_response = client.show_metric_value(show_metric_value_request)
            # 输出json格式的字符串响应
            print(show_metric_value_response)
        except ServiceResponseException as e:
            print("HttpStatusCode: "+e.status_code)
            print("RequestId: "+e.request_id)
            print("ErrorCode: "+e.error_code)
            print("ErrorMsg: "+e.error_msg)

    @staticmethod
    def show_property_raw_value(client):
        """
        获取资产属性历史值
        """
        try:
            # 构造请求参数
            show_property_raw_value_request = ShowPropertyRawValueRequest()
            show_property_raw_value_request.asset_id = "your assetId"
            raw_request = RawRequest()
            raw_request.limit = 2000
            property_names = []
            property_names.append("p2")
            raw_request.property_names = property_names
            time_span = TimeSpanDT()
            # 设置起止时间,UTC格式字符串
            time_span._from = "2020-11-21T10:45:32Z"
            time_span.to = "2020-11-27T10:45:32Z"
            raw_request.time_span = time_span
            show_property_raw_value_request.body = raw_request
            show_property_raw_value_response = client.show_property_raw_value(show_property_raw_value_request)
            # 输出json格式的字符串响应
            print(show_property_raw_value_response)
        except ServiceResponseException as e:
            print("HttpStatusCode: "+e.status_code)
            print("RequestId: "+e.request_id)
            print("ErrorCode: "+e.error_code)
            print("ErrorMsg: "+e.error_msg)

    @staticmethod
    def __get_show_metric_value_request():
        """
        构造获取资产属性聚合值请求参数
        """
        show_metric_value_request = ShowMetricValueRequest()
        show_metric_value_request.asset_id = "your assetId"
        get_metrics_value = GetMetricsValue()
        # 设置查询类型,经过转换计算的序列值(transform)、经过聚合计算的序列值(aggregate)
        get_metrics_value.type = "transform"
        transform_metrics_request = TransformMetricsRequest()
        transform_metrics_request.limit = 50
        time_span = TimeSpanDT()
        # 设置起止时间,UTC格式字符串
        time_span._from = "2020-12-25T00:00:00Z"
        time_span.to = "2020-12-27T00:00:00Z"
        transform_metrics_request.time_span = time_span
        metrics = []
        dt_transform_metrics = DTTransformMetrics()
        dt_transform_metrics.expression = "floor(y)"
        dt_transform_metrics.metric_name = "y2"
        inputs = []
        metric_input = MetricInput()
        metric_input.name = "y"
        metric_input.property_name = "p2"
        inputs.append(metric_input)
        dt_transform_metrics.inputs = inputs
        metrics.append(dt_transform_metrics)
        transform_metrics_request.metrics = metrics
        get_metrics_value.transform = transform_metrics_request
        show_metric_value_request.body = get_metrics_value
        return show_metric_value_request

6. 参考

详细了解数据分析，请参考IoT数据分析

更多关于SDK的调用，请参考华为云开发者 Python 软件开发工具包（Python SDK）

7. 修订记录