微信小程序通过url 上传远端图片 到微信小程序临时素材库 java

	微信小程序在实现客服功能时，有时候需要自动回复一张图片给用户，这时候，我们需要提前将图片上传到微信小程序的素材库。
	然后微信客服才能将图片回复给用户。在这儿，我想插句嘴，微信小程序目前只支持临时素材库，不支持永久素材库。
	小编在做素材上传时，在这儿被这个坑坑了许久。

import com.alibaba.fastjson.JSONObject;
import com.dftcmedia.tckk.microservice.sskx.microapp.config.ClientProperties;
import com.dftcmedia.tckk.microservice.sskx.microapp.enums.MicroServiceCodeEnum;
import com.dftcmedia.tckk.microservice.sskx.microapp.exception.MicroException;
import com.dftcmedia.tckk.microservice.sskx.microapp.service.SensitivewordsService;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.mime.HttpMultipartMode;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.springframework.stereotype.Component;
import javax.annotation.Resource;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;

@Component
@Slf4j
public class UploadMediaIdUtil {
    @Resource
    private SensitivewordsService sensitivewordsService;
    public String uploadMedia(){
        JSONObject jsonObject = uploadImage(“图片资源的URL”);
        if(jsonObject==null|| StringUtils.isBlank(jsonObject.getString("media_id"))){
            log.error("上传素材库"+jsonObject);
            throw new MicroException(MicroServiceCodeEnum.TARGET_NOT_EXIST);
        }
        return jsonObject.getString("media_id");
    }

    private  JSONObject uploadImage(String mediaUrl)  {
    //此处是获取微信小程序的AccessToken  前几篇文章对如何获取有专门说明，此处就不再赘述
        String accessToken = sensitivewordsService.getAccessToken();
        String url = "https://api.weixin.qq.com/cgi-bin/media/upload?access_token="+accessToken+"&type=image";
        try{
            byte[] file = getFile(mediaUrl);
            CloseableHttpClient httpclient = HttpClients.createDefault();
            CloseableHttpResponse response = null;
            HttpPost request = new HttpPost(url);
            MultipartEntityBuilder builder = MultipartEntityBuilder.create();
            builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);
            builder.addBinaryBody("media", file, ContentType.DEFAULT_BINARY, "1.jpg");
            HttpEntity entity = builder.build();
            request.setEntity(entity);
            HttpResponse resp = httpclient.execute(request);
            HttpEntity httpEntity = resp.getEntity();
            String result = EntityUtils.toString(httpEntity, "UTF-8");// 转成string
            JSONObject jso = JSONObject.parseObject(result);
            log.info("上传临时素材结果："+jso);
            return jso;
        }catch (Exception e){
            e.printStackTrace();
            return null;
        }
    }

    private static byte[] getFile(String url) throws IOException{
        URL urlConet = new URL(url);
        HttpURLConnection con = (HttpURLConnection)urlConet.openConnection();
        con.setRequestMethod("GET");
        con.setConnectTimeout(4 * 1000);
        InputStream inStream = con .getInputStream();    //通过输入流获取图片数据
        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
        byte[] buffer = new byte[2048];
        int len = 0;
        while( (len=inStream.read(buffer)) != -1 ){
            outStream.write(buffer, 0, len);
        }
        inStream.close();
        byte[] data =  outStream.toByteArray();
        return data;
    }
}