微信公众号开发之获得素材列表

对于获得公众号的素材列表首先需要阅读微信开发者手册

开发准备工具

测试公众号

内网穿透HTTP地址（微信对本地服务的通信对一些，公众号信息的获取不需要）

具体参考：

https://developers.weixin.qq.com/doc/offiaccount/Getting_Started/Overview.html

[外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-QgOcoCTL-1625189967278)(C:\Users\wang\AppData\Roaming\Typora\typora-user-images\image-20210630113832423.png)]

微信获得素材列表接口：https://api.weixin.qq.com/cgi-bin/material/batchget_material?access_token=ACCESS_TOKEN

需要同过post方法去向微信接口发送下列数据

{
    
    "type":TYPE,
    "offset":OFFSET,
    "count":COUNT
}

其中最为重要的是微信Access_Token的获得

access_token是微信公众号的全局权限令牌因为它两小时刷新一次所以我们只能将其存储（数据库，缓存并且设置时间戳）

access_token封装实体类

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.ToString;
import java.util.Date;

@Data
@ToString
@NoArgsConstructor
@AllArgsConstructor
public class Token {
    
    private Date date;//获得时间
    private String accessToken;//令牌
    private int expiresIn;//微信设置的access_token有效时间
}

access_token调用工具类

import com.alibaba.fastjson.JSONObject;
import com.test.weixindemo.Pojo.Token;

import com.test.weixindemo.Pojo.Url;
import com.test.weixindemo.mapper.TokenMapper;
import com.test.weixindemo.mapper.UrlMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
@Component
public class TokenUtil {
    

    @Autowired
    private TokenMapper ats;

    private static TokenMapper accessTokenService;
    @Resource
    private UrlMapper urlMapper;
    private static UrlMapper urlService;
    @PostConstruct
    public void init(){
    
        accessTokenService = ats;
        urlService=urlMapper;
    }

    public static String getToken() throws ParseException {
    
        Token accessToken = accessTokenService.checkDate(7200);
        //上次创建的时间
        Date creatTime = accessToken.getDate();
        //格式化时间
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH-mm-ss");
        String date = sdf.format(creatTime);
        //将时间转换成毫秒值
        long lastTime = sdf.parse(date).getTime();
        //获取到现在的毫秒值
        long nowTime = System.currentTimeMillis();
        //如果时差大于2小时则重新获取access_token
        if (nowTime - lastTime > 60*60*1000) {
    
            Url urls= urlService.getUrl("access_token");
             String  url=  urls.getUrl();
            JSONObject jsonObject = CommonUtil.httpRequest(url,"GET",null);
            String access_token = (String) jsonObject.get("access_token");
            Integer ei = (Integer) jsonObject.get("expires_in");
            if (access_token != null) {
    
                Token token = new Token();
                Date d = new Date();
                token.setDate(d);
                token.setAccessToken(access_token);
                token.setExpiresIn(ei);
                accessTokenService.updateToken(token);
            }
        }
        return accessTokenService.getToken();
    }
}

http交互工具类

import com.alibaba.fastjson.JSONObject;
import javax.net.ssl.HttpsURLConnection;
import java.io.*;
import java.net.URL;
import java.nio.charset.StandardCharsets;
public class CommonUtil {
    
    public synchronized static JSONObject httpRequest(String requestUrl ,String requestMethod,String outputStr) {
    
        JSONObject jsonObject = null;
        StringBuilder buffer = new StringBuilder();
        try {
    

            URL url = new URL(requestUrl);
            HttpsURLConnection httpUrlConn = (HttpsURLConnection) 		        url.openConnection();
            httpUrlConn.setDoOutput(true);
            httpUrlConn.setDoInput(true);
            httpUrlConn.setUseCaches(false);
            httpUrlConn.setRequestMethod(requestMethod);
            if (null != outputStr) {
    
                OutputStream outputStream = httpUrlConn.getOutputStream();
                // 注意编码格式
                outputStream.write(outputStr.getBytes(StandardCharsets.UTF_8));
                outputStream.close();
                           }
            // 将返回的输入流转换成字符串
            InputStream inputStream = httpUrlConn.getInputStream();
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream, StandardCharsets.UTF_8);
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
            String str = null;
            while ((str = bufferedReader.readLine()) != null) {
    
                buffer.append(str);
            }
            bufferedReader.close();
            inputStreamReader.close();
            // 释放资源
            inputStream.close();
            inputStream = null;
            httpUrlConn.disconnect();
            jsonObject = JSONObject.parseObject(buffer.toString());
        } catch (Exception e) {
    
            e.printStackTrace();
        }
        return jsonObject;
    }


}

获得素材列表类

import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
import com.test.weixindemo.Pojo.Material;
import com.test.weixindemo.Pojo.MaterialParam;
import com.test.weixindemo.mapper.UrlMapper;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.util.ArrayList;
import java.util.List;


@Component

public class GetMaterial {
    


    @Resource
    private UrlMapper urlMapper;
    private static UrlMapper urlService;
    @PostConstruct
    public void init(){
    
        urlService=urlMapper;
    }

    public static List<Material> getMaterial(String accessToken,String type, int offset, int count) {
    
         String MATERIAL =urlService.getUrl("Material").getUrl() ;
        List<Material> list = new ArrayList<Material>();//定义实体集合
        String outputStr = "";
        String requestUrl = MATERIAL.replace("ACCESS_TOKEN", accessToken);
        MaterialParam materialParam = new MaterialParam();
        materialParam.setCount(count);
        materialParam.setOffset(offset);
        materialParam.setType(type);
        JSONObject jsonObject = new JSONObject();
        jsonObject = (JSONObject) JSONObject.toJSON(materialParam);
        outputStr = jsonObject.toJSONString();
        jsonObject = CommonUtil.httpRequest(requestUrl, "POST", outputStr);
        if (null != jsonObject) {
    
            JSONArray jsonArray = jsonObject.getJSONArray("item");
            for (int i = 0; i < jsonArray.size(); i++) {
    
                JSONObject json = (JSONObject) jsonArray.get(i);
                json = json.getJSONObject("content");
                JSONArray arr = json.getJSONArray("news_item");
                json = (JSONObject) arr.get(0);
                Material material = new Material();
                String title = json.getString("title");
                String author = json.getString("author");
                String digest = json.getString("digest");
                String thumb_media_id = json.getString("thumb_media_id");
                String url = json.getString("url");
                String content = json.getString("content");
                material.setTitle(title);
                material.setAuthor(author);
                material.setDigest(digest);
                material.setThumb_media_id(thumb_media_id);
                material.setUrl(url);
                material.setContent(content);
                material.setShow_cover_pic(1);
                list.add(material);
            }
        }
        return list;
    }
}

);
material.setUrl(url);
material.setContent(content);
material.setShow_cover_pic(1);
list.add(material);
}
}
return list;
}
}

在本次测试中所有接口均写入数据方便调用，修改。