仓颉应用开发之——网络访问(20)

一 概述

• 应用隐私保护
• ohos.net.http网络请求介绍
• ohos.net.http网络访问示例

二 应用隐私保护

2.1 应用隐私说明

• 同Android、iOS手机类型，涉及隐私权限访问时要实现声明并争得用户同意
• 仓颉应用的隐私权限声明位于module.json5的module下的"requestPermissions":[]
• 该权限包含name(权限名)、reason(原因)、usedScene(场景)、when(何时)组成的json，name必须，其他可省略

2.2 示例(相机权限)

// module.json5
{
  "module" : {
    ...
    "requestPermissions":[
      {
        "name" : "ohos.permission.CAMERA",
        "reason": "$string:camera_reason",
        "usedScene": {
          "abilities": [
            "EntryAbility"
          ],
          "when":"inuse"
        }
      },...
    ]
  }
}

三 ohos.net.http网络请求介绍

3.1 网络请求过程

1. 导入网络请求模块import ohos.net.http.*
2. 创建httpRequest，执行HTTP请求任务
3. httpRequest.onHeadersReceive({header: })设置HTTP响应头
4. HttpRequestOptions(method:RequestMethod.POST,header)设置请求Option
5. httpRequest.request()发送网络请求并解析

3.2 常见类或方法

No	类或方法	说明
1	func createHttp()	创建一个HTTP请求
2	class HttpRequest	执行HTTP请求任务
3	destroy()	中断请求任务

四 ohos.net.http网络访问示例

API接口：https://wanandroid.com/popular/column/json

4.1 module.json5添加访问权限

"requestPermissions": [
      {
        "name": "ohos.permission.INTERNET"
      }
 ]

4.2 实体类封装(PopularBean)

package ohos_app_cangjie_entry.bean
import serialization.serialization.*
import std.math.*
import encoding.json.*
import std.collection.*

public class PopularBean  <:Serializable<PopularBean> {


    public var errorCode:Int64 = 0
    public var errorMsg:String = ""
    public var data: Option<Array<PopularData>>  = Option<Array<PopularData>>.None

    public func serialize(): DataModel {
        return DataModelStruct()
        .add(field<Option<Array<PopularData>>>("data", data))
        .add(field<Int64>("errorCode", errorCode))
        .add(field<String>("errorMsg", errorMsg))
    }

    public static func deserialize(dm: DataModel): PopularBean {
        var dms = match (dm) {
            case data: DataModelStruct => data
            case _ => throw Exception("this data is not DataModelStruct")
        }
        var result = PopularBean()
        result.data = Option<Array<PopularData>>.deserialize(dms.get("data"))
        result.errorCode = Int64.deserialize(dms.get("errorCode"))
        result.errorMsg = String.deserialize(dms.get("errorMsg"))

        return result
    }


}
public class PopularData <:Serializable<PopularData> {

    public var chapterId:Int64 = 0
    public var chapterName:String = ""
    public var columnId:Int64 = 0
    public var id:Int64 = 0
    public var name: String = ""
    public var subChapterId:Int64 = 0
    public var subChapterName:String = ""
    public var url:String = ""
    public var userId:Int64 = 0

     public func serialize(): DataModel {
        return DataModelStruct()
        .add(field<Int64>("chapterId", chapterId))
        .add(field<String>("chapterName", chapterName))
        .add(field<Int64>("columnId", columnId))
        .add(field<Int64>("id", id))
        .add(field<String>("name", name))
        .add(field<Int64>("subChapterId", subChapterId))
        .add(field<String>("subChapterName", subChapterName))
        .add(field<String>("url", url))
        .add(field<Int64>("userId", userId))

    }

    public static func deserialize(dm: DataModel): PopularData {
        var dms = match (dm) {
            case data: DataModelStruct => data
            case _ => throw Exception("this data is not DataModelStruct")
        }
        var result = PopularData()
        result.chapterId = Int64.deserialize(dms.get("chapterId"))
        result.chapterName = String.deserialize(dms.get("chapterName"))
        result.columnId = Int64.deserialize(dms.get("columnId"))
        result.id = Int64.deserialize(dms.get("id"))
        result.name = String.deserialize(dms.get("name"))
        result.subChapterId = Int64.deserialize(dms.get("subChapterId"))
        result.subChapterName = String.deserialize(dms.get("subChapterName"))
        result.url = String.deserialize(dms.get("url"))
        result.userId = Int64.deserialize(dms.get("userId"))
        return result
    }
}

4.3 API接口

package ohos_app_cangjie_entry.api
import ohos.net.http.*
import ohos.base.*
import std.collection.*
import ohos_app_cangjie_entry.bean.*
import ohos.hilog.*
import std.time.*
import std.sync.*
import ohos.state_manage.*
let mtx = ReentrantMutex()

public class APiRequest {
    let baseURL = 'https://www.wanandroid.com/'
    let httpRequest = createHttp();
    var responseResult = ResponseResult()
    var isRequestFinish = AtomicBool(false)

    public func request():ResponseResult{
        let option = HttpRequestOptions(
            method: RequestMethod.GET, // 可选，默认为http.RequestMethod.GET
            expectDataType: HttpDataType.STRING, // 可选，指定返回数据的类型
            usingCache: true, // 可选，默认为true
            priority: 1, // 可选，默认为1
            // 开发者根据自身业务需要添加header字段
            header: HashMap<String, String>([("content-type", "application/json")]),
            readTimeout: 60000, // 可选，默认为60000ms
            connectTimeout: 60000, // 可选，默认为60000ms
            usingProtocol: HttpProtocol.HTTP1_1, // 可选，协议类型默认值由系统自动指定
            usingProxy: UsingProxy.USE_DEFAULT, //可选，默认不使用网络代理，自API 10开始支持该属性
            )

        try {
             // Hilog.info(0, "test", "resp===: 开始请求")
              //https://wanandroid.com/harmony/index/json
             //https://wanandroid.com/popular/column/json
              httpRequest.request('https://wanandroid.com/popular/column/json', {err, resp =>
              if (let Some(e) <- err) {
                  Hilog.error(0, "test","exception: ${e.message}")
                  this.responseResult.errorCode = 400
                  this.responseResult.errorMsg = e.message
                  this.responseResult.data = ""
             }
              if (let Some(r) <- resp) {
                  Hilog.info(0, "test", "resp===: ${r.result}")
                  //r.responseCode
                  this.responseResult.errorCode = 200
                  this.responseResult.errorMsg = "请求成功"
                  this.responseResult.data = r.result.toString()

              } else {
                  Hilog.error(0, "test", "response is none")
                  this.responseResult.errorCode = 400
                  this.responseResult.errorMsg = "response is none"
                  this.responseResult.data = ""
              }}, options: option)
             sleep(Duration.second * 1)
             //Hilog.info(0, "test", "resp===: 结束请求")
             return responseResult
        }catch (exception:Exception) {
              this.responseResult.errorCode = 400
              this.responseResult.errorMsg = "${exception.message}"
              this.responseResult.data = "出错了"
              return responseResult
        }finally {
            //sleep(Duration.second * 1)
            //return responseResult
        }
    }
}

4.4 UI中调用接口

protected override func onPageShow() {

       var requestResult = APiRequest().request()
       Hilog.printInfo("printInfo","${requestResult.data}")

       var jve:JsonValue = JsonValue.fromStr(requestResult.data)
       var dml = DataModel.fromJson(jve)
       Hilog.printInfo("printInfo","harmony=${dml.toJson()}")
       var popularData:PopularBean = PopularBean.deserialize(dml)

  }

五 参考

• HarmonyOS NEXT Beta1-应用隐私保护
• HarmonyOS NEXT Beta1-ohos.net.http