API 参考文档

主要的 API 参考文档如下：

from iotedgeapplicationlinksdk

• getLogger()

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from iotedgeapplicationlinksdk.client

• get_application_config()
• get_application_name()
• get_gateway_product_sn()
• get_gateway_device_sn()
• publish()
• register_callback()
• natsPublish()
• natsSubscribe()

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getLogger()

返回应用内置 logger。

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get_application_config()

返回应用配置。

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get_application_name()

返回应用名称。

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get_gateway_product_sn()

返回应用网关 ProductSN。

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get_gateway_device_sn()

返回应用网关 DeviceSN。

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publish()

上报消息到 Link IoT Edge。参数(topic: str, payload: bytes)

• topicstr: 上报消息到 Link IoT Edge 的 mqtt topic。
• payloadbytes: 上报消息到 Link IoT Edge 的消息内容

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register_callback

设置应用接收消息的回调函数，参数(cb, rrpc_cb)

• cbfunc: 应用消息回调，例如： def callback(topic:str, msg:bytes): print(str(msg,'utf-8')
• rrpc_cbfunc: 应用 RRPC 消息回调，例如： def callback(topic:str, msg:bytes): print(str(msg,'utf-8')

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natsPublish(subject, payload)

通过 nats Publish 消息

• subjectstr: nats Subject
• payloadbytes: nats 消息

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natsSubscribe(subject, queue, callback)

通过 nats 订阅 主题

• subjectstr: nats Subject
• queuestr: nats 队列
• callbackfunc(msg): nats 消息回调， msg 为 nats 消息

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Demo

import json
import logging
import time

from iotedgeapplicationlinksdk import getLogger
from iotedgeapplicationlinksdk.client import get_application_config, get_application_name, get_gateway_product_sn, get_gateway_device_sn, publish, register_callback

# 配置log
log = getLogger()
log.setLevel(logging.DEBUG)

# 主函数
if __name__ == "__main__":
    try:
        # 获取应用配置信息
        appConfig = get_application_config()
        log.info('app config:{}'.format(appConfig))

        # 从应用配置获取设备数据上报周期
        uploadPeriod = 5
        if "period" in appConfig.keys() and isinstance(appConfig['period'], int):
            uploadPeriod = int(appConfig['period'])

        appName = get_application_name()
        productSN = get_gateway_product_sn()
        deviceSN = get_gateway_device_sn()
        log.info('app info:{}, {}, {}'.format(appName, productSN, deviceSN))

        # 设置应用上报topic
        topic = '/{}/{}/upload'.format(productSN, deviceSN)

        # 设置应用消息回调
        def callback(topic: str, payload: bytes):
            log.info("recv message from {} : {}".format(topic, str(payload)))

        # 设置应用RRPC消息回调
        def rrpc_callback(topic: str, payload: bytes):
            log.info("recv rrpc message from {} : {}".format(
                topic, str(payload)))

        register_callback(callback, rrpc_callback)
        i = 0
        # 周期上报消息
        while True:
            relayStatus = ("on", "off")[i % 2 == 0]
            payload = {
                "timestamp": time.time(),
                'RelayStatus': relayStatus
            }

            byts = json.dumps(payload).encode('utf-8')

            publish(topic, byts)

            log.info("upload {} : {}".format(topic, str(byts)))

            time.sleep(uploadPeriod)
            i = i+1
            if (i > 1000):
                i = 1

    except Exception as e:
        log.error('load app config error: {}'.format(str(e)))
        exit(1)