2023新版Onenet+AndroidStudio(GET获取数据,Onenet安全鉴权)

概要

最近做了个大作业,是用AndroidStudio获取Onenet上面数据的。
本文介绍两个方法,GET()和POST()。用的是java语言,kotlin语言可以直接搜kotlin,get方法,和java的没什么区别。

整体架构流程

首先要引入依赖和库,比如联网的,Okhttp的库
然后是核心的GET和POST代码,这里要注意的是鉴权,我找了好久才在官网找到安全鉴权的方式。(这里吐槽一下Onenet的开发者文档的可查询性实在是太弱了)
最后是获取到返回数据。
所有文件

技术名词解释

1,Okhttp:OkHttp是一个开源的Java库,用于处理HTTP请求。它是Square公司开发的,设计简单而灵活,是Android开发中广泛使用的HTTP客户端。
示例代码:

import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

public class OkHttpExample {
    public static void main(String[] args) throws Exception {
        OkHttpClient client = new OkHttpClient();

        Request request = new Request.Builder()
                .url("https://www.baidu.com")
                .build();

        try (Response response = client.newCall(request).execute()) {
            System.out.println(response.body().string());
        }
    }
}

2,安全鉴权:在OkHttp中,.header 方法用于设置HTTP请求头。通过这个方法,你可以添加自定义的请求头信息。以下是一个简单的示例,演示如何在OkHttp中使用.header方法:

import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

public class OkHttpHeaderExample {
    public static void main(String[] args) throws Exception {
        OkHttpClient client = new OkHttpClient();

        // 构建请求时使用 .header 方法添加自定义的请求头
        Request request = new Request.Builder()
                .url("https://www.example.com")
                .header("Authorization", "Bearer your_access_token") // 添加 Authorization 请求头
                .build();

        try (Response response = client.newCall(request).execute()) {
            System.out.println(response.body().string());
        }
    }
}

两个类的声明

第一个是JsonRootBean.java文件(这个文件和MainActivity平行)

package com.example.myapplication;

import java.util.List;

public class JsonRootBean {//Json转换
    int code;
List<Data> data;
    String msg;
    String request_id;

}

第二个是data.java

package com.example.myapplication;
import androidx.annotation.VisibleForTesting;

import java.util.List;
public class Data {//用list存放获取的数据流
    String identifier;
    String time;
    String value;
    String data_type;
    String access_mode;
    String name;
    String description;
}

鉴权生成(Token)

Onenet的鉴权介绍网址:安全鉴权
鉴权码生成代码:API鉴权
我贴一下我的代码token.java

package com.example.myapplication;

import android.os.Build;

import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.util.Base64;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;

public class Token {
    public static String TOKEN = "默认值";

    public static void setMyString(String newValue) {
        TOKEN = newValue;
    }
    public static String assembleToken(String version, String resourceName, String expirationTime, String signatureMethod, String accessKey)
            throws UnsupportedEncodingException, NoSuchAlgorithmException, InvalidKeyException {
        StringBuilder sb = new StringBuilder();
        String res = URLEncoder.encode(resourceName, "UTF-8");
        String sig = URLEncoder.encode(generatorSignature(version, resourceName, expirationTime, accessKey, signatureMethod), "UTF-8");
        sb.append("version=")
                .append(version)
                .append("&res=")
                .append(res)
                .append("&et=")
                .append(expirationTime)
                .append("&method=")
                .append(signatureMethod)
                .append("&sign=")
                .append(sig);
        return sb.toString();
    }

    public static String generatorSignature(String version, String resourceName, String expirationTime, String accessKey, String signatureMethod)
            throws NoSuchAlgorithmException, InvalidKeyException {
        String encryptText = expirationTime + "n" + signatureMethod + "n" + resourceName + "n" + version;
        String signature = null;
        byte[] bytes = HmacEncrypt(encryptText, accessKey, signatureMethod);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            signature = Base64.getEncoder().encodeToString(bytes);
        }
        return signature;
    }

    public static byte[] HmacEncrypt(String data, String key, String signatureMethod)
            throws NoSuchAlgorithmException, InvalidKeyException {
        //根据给定的字节数组构造一个密钥,第二参数指定一个密钥算法的名称
        SecretKeySpec signinKey = null;
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            signinKey = new SecretKeySpec(Base64.getDecoder().decode(key),
                    "Hmac" + signatureMethod.toUpperCase());
        }

        //生成一个指定 Mac 算法 的 Mac 对象
        Mac mac = null;
        mac = Mac.getInstance("Hmac" + signatureMethod.toUpperCase());

        //用给定密钥初始化 Mac 对象
        mac.init(signinKey);

        //完成 Mac 操作
        return mac.doFinal(data.getBytes());
    }

    public enum SignatureMethod {
        SHA1, MD5, SHA256;
    }

    public static void main(String args) throws UnsupportedEncodingException, NoSuchAlgorithmException, InvalidKeyException {
        String version = "2022-05-01";
        String resourceName = "userid/这里写你的用户id";
        String expirationTime = System.currentTimeMillis() / 1000 + 100 * 24 * 60 * 60 + "";
        String signatureMethod = SignatureMethod.SHA1.name().toLowerCase();
        String accessKey = "这里放你的AccessKey(在Onenet官网的账户信息里面)";
        String token = assembleToken(version, resourceName, expirationTime, signatureMethod, accessKey);
        setMyString(token);
    }
}

MainActivity代码(Java)

 public class MainActivity extends AppCompatActivity {
 String token="鉴权参数";
 protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);//UI的基本布局
        try {
            Token.main("拿鉴权码,这里参数无所谓的");
        } catch (UnsupportedEncodingException | NoSuchAlgorithmException | InvalidKeyException e) {
            throw new RuntimeException(e);
        }
        token=Token.TOKEN;//赋值Token,把鉴权信息拿到
`        requestPermissions(new String[]{"android.permission.INTERNET"}, 1);
        Get();}
        

如图上面是主函数代码,获取网络请求后直接GET就好了。

public void Get(){
         new Thread(new Runnable() {
                    @Override
                    public void run() {
               		while (true) {
                    try {
                        OkHttpClient client = new OkHttpClient();
                        //http(s)://iot-api.heclouds.com/thingmodel/query-device-property?product_id=w50WLDzGBb&device_name=light
                        //http://iot-api.heclouds.com/thingmodel/query-thing-model?product_id=w50WLDzGBb
                        Request request = new Request.Builder().url("http://iot-api.heclouds.com/thingmodel/query-device-property?product_id=这里输入你的产品id&device_name=你的设备名称")
                                .header("Authorization",token)
                                .build();
                        Response response = client.newCall(request).execute();
                        String responseData = response.body().string();
                          JsonRootBean app = new Gson().fromJson(responseData, JsonRootBean.class);

                       value=app.data.get(0).value.toString();//获得亮度
                        brightnessDisplay.post(new Runnable() {
                            @Override
                            public void run() {
                                brightnessDisplay.setText(String.format("BrightnessRightNow:%s", value));
                            }
                        });
                    } catch (IOException e) {
                        e.printStackTrace();}
                   try {
                       Thread.sleep(1000);
                   } catch (InterruptedException e) {
                       throw new RuntimeException(e);
                   }//延时一秒获取一次亮度
               }
            }
        }).start();

在.header后面这个token,就是我们要的鉴权码。
上面代码中的jsonRootbean是我自己的一个类,我GET获取的数据是一段json格式的数组

{"code":0,
"data":[{"identifier":"bright","time":1700127636130,"value":"0.600000","data_type":"float","access_mode":"读写","name":"bright"},
{"identifier":"setbright","data_type":"int32","access_mode":"读写","name":"setbright"},
{"identifier":"state","time":1698234341316,"value":"2","data_type":"enum","access_mode":"读写","name":"state","description":"工作模式"},
{"identifier":"time","data_type":"date","access_mode":"读写","name":"time"}],
"msg":"succ",
"request_id":"f97096fb25a94f2884a043c510821485"}

ONENET官网关于GET方法的返回数组
可以看到有4个大参数,code,data,msg,request_id
data是一个数组,在数组的每一个项里面又包含4个小参数(如下图),identifier,data_type,access_mode,name
所以我们核心的是获取到data里面的这个value值,因此GET获取到数据后,采用了下面这个方式提取到value

 Response response = client.newCall(request).execute();
                        String responseData = response.body().string();
                          JsonRootBean app = new Gson().fromJson(responseData, JsonRootBean.class);

                       value=app.data.get(0).value.toString();//获得亮度

小结

搞定鉴权就简单了很多很多。有问题私信问

本图文内容来源于网友网络收集整理提供,作为学习参考使用,版权属于原作者。
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