微信JS-SDK实现上传图片功能

时间：2017-09-13 13:03:35 收藏：0 阅读：1690

　　最近在项目开放中，有一个在微信WEB项目中上传图片的需求，一开始使用了传统的<input type="file">的方式去实现，但是后面发现在使用这种传统模式时会由于手机系统的差异而导致一系列的问题，后改用微信JSSDK的方式来实现。

　　总的来说，利用JSSDK来实现该功能一共分为四步。

　　1. 调用wx.config()，初始化jssdk的配置，并在jsApiList中配置上传图片需要的四个api(‘chooseImage‘,‘previewImage‘,‘uploadImage‘,‘downloadImage‘)

wx.config({
    debug : false,
    appId : data.appId,
    timestamp : data.timestamp,
    nonceStr : data.nonceStr,
    signature : data.signature,
    jsApiList : [
        ‘chooseImage‘,
        ‘previewImage‘,
        ‘uploadImage‘,
        ‘downloadImage‘ 
    ]
});

　　2.点击图片时，调用wx.chooseImage()，让用户去选择图片或拍照

 1 function wxChooseImage() {
 2     wx.chooseImage({
 3         count: 1,
 4         sizeType: [‘original‘, ‘compressed‘],
 5         sourceType: [‘album‘, ‘camera‘],
 6         success: function (data) {  
 7             var localIds = data.localIds[0].toString();
 8             wxuploadImage(localIds);  
 9         }
10     });
11 }

　　3.选择完图片后调用wx.chooseImage()，将图片上传到微信服务器

 1 function wxuploadImage(e) {
 2     layer.load(1);
 3     wx.uploadImage({  
 4         localId: e,
 5         isShowProgressTips: 0,
 6         success: function (res) {
 7             fileUpload(res.serverId);
 8         }
 9     });  
10 }

　　4.利用mediaId将图片从微信服务器下载到本地或项目的图片服务器路径下，并展示图片

 1 function fileUpload(mediaId) {
 2     $.ajax({ 
 3         url: KY.basePath + "/image/upload.htm",
 4         dataType: ‘json‘,
 5         data: {
 6             "mi": mediaId
 7         },
 8         type: "post",
 9         success: function(result) { 
10             $("#imghead").attr("src", KY.imageServer + result.path);
11         }
12     }); 
13 }

附：服务端从微信服务器下载图片的代码，在此处，我是将图片从微信服务器下载后调用另一个专门负责上传图片的项目去进行的上传操作，大家也可以在第73行代码获取到流之后下载到本地。

  1 package com.hyde.carelink2.wechat.utils;
  2 
  3 import java.io.ByteArrayOutputStream;
  4 import java.io.IOException;
  5 import java.io.InputStream;
  6 import java.net.HttpURLConnection;
  7 import java.net.URL;
  8 import java.util.ArrayList;
  9 import java.util.HashMap;
 10 import java.util.List;
 11 import java.util.Map;
 12 
 13 import org.apache.commons.httpclient.NameValuePair;
 14 import org.apache.http.entity.ContentType;
 15 import org.apache.http.entity.mime.content.ByteArrayBody;
 16 import org.slf4j.Logger;
 17 import org.slf4j.LoggerFactory;
 18 
 19 import com.fasterxml.jackson.databind.ObjectMapper;
 20 import com.hyde.carelink2.wechat.domain.upload.UploadImagResponse;
 21 import com.hyde.carelink2.wechat.service.wechat.WechatServerCenter;
 22 import com.hyde.common.StatusCode;
 23 import com.hyde.common.enums.ImageToken;
 24 import com.hyde.common.enums.ProjectType;
 25 import com.hyde.common.utils.HttpUtil;
 26 import com.hyde.config.enums.ConfigType;
 27 import com.hyde.config.impl.CommonConfig;
 28 
 29 /**
 30  * @author WangHuijie
 31  */
 32 public class DownloadImageUtil {
 33 
 34     private final static Logger LOGGER = LoggerFactory.getLogger(DownloadImageUtil.class);
 35     
 36     private static ObjectMapper objectMapper = new ObjectMapper();
 37 
 38     /**
 39      * 从微信服务器获取媒体文件
 40      * 
 41      * @param param
 42      * @param mediaId
 43      * @param request
 44      * @return
 45      */
 46     public static Map<String, String> getImageFromWechat(String mediaId) {
 47 
 48         Map<String, String> map = new HashMap<String, String>();
 49         String accessToken = ""; // 接口访问凭证
 50         try {
 51             accessToken = WechatServerCenter.getAccessToken();
 52         } catch (Exception e) {
 53             LOGGER.error(e.getMessage(), e);
 54         }
 55         String filePath = "";
 56         // 拼接请求地址
 57         String requestUrl = "http://file.api.weixin.qq.com/cgi-bin/media/get?access_token=" + accessToken + "&media_id=" + mediaId;
 58         try {
 59             URL url = new URL(requestUrl);
 60             HttpURLConnection conn = (HttpURLConnection) url.openConnection();
 61             conn.setDoInput(true);
 62             conn.setDoOutput(true);
 63             conn.setRequestMethod("GET");
 64             conn.setRequestProperty("Content-Type", "application/form-data");
 65             InputStream inputStream = conn.getInputStream();
 66 
 67             if (inputStream != null) {
 68                 HttpURLConnection conn1 = (HttpURLConnection) url.openConnection();
 69                 conn1.setDoInput(true);
 70                 conn1.setDoOutput(true);
 71                 conn1.setRequestMethod("GET");
 72                 conn1.setRequestProperty("Content-Type", "application/form-data");
 73                 InputStream inputStream1 = conn1.getInputStream();
 74 
 75                 if (inputStream1 != null) {
 76                     // 根据内容类型获取扩展名
 77                     String contentType = conn1.getHeaderField("Content-Type");
 78                     String expandName = getFileexpandedName(contentType);
 79                     String fileName = mediaId + expandName;
 80                     filePath = getUploadServerPath(inputStream1, contentType, fileName);
 81                     map.put("path", filePath);
 82                     map.put("code", String.valueOf(StatusCode.SUCCESS.getIndex()));
 83                     map.put("msg", StatusCode.SUCCESS.getMessage());
 84                 } else {
 85                     map.put("code", String.valueOf(StatusCode.ERROR.getIndex()));
 86                     map.put("msg", StatusCode.ERROR.getMessage());
 87                 }
 88             } else {
 89                 map.put("code", String.valueOf(StatusCode.ERROR.getIndex()));
 90                 map.put("msg", StatusCode.ERROR.getMessage());
 91             }
 92             inputStream.close();
 93             conn.disconnect();
 94         } catch (Exception e) {
 95             LOGGER.error(e.getMessage(), e);
 96         }
 97         return map;
 98     }
 99 
100     public static String getUploadServerPath(InputStream inputStream, String contentType, String fileName) {
101         
102         String filePath = null;
103         byte[] bytes = new byte[0];
104         try {
105             bytes = toByteArray(inputStream);
106         } catch (IOException e) {
107             LOGGER.error(e.getMessage(), e);
108         }
109         String token = "DM5344d93e19c41adb5e0f5531bdd0336";
110         ProjectType projectType = ProjectType.CARELINK2;
111         ImageToken type = ImageToken.CARELINK2_USER_PORTRAIT;
112         UploadImagResponse response = uploadImage(bytes, token, contentType, fileName, projectType, type);
113         if (response != null) {
114             filePath = response.getFilePath();
115         }
116         return filePath;
117     }
118 
119     /**
120      * 执行文件上传到图片服务器
121      * 
122      * @param bytes
123      * @param token
124      * @param contentType
125      * @param fileName
126      * @param param
127      * @return
128      */
129     protected static UploadImagResponse uploadImage(byte[] bytes, String token, String contentType, String fileName, ProjectType projectType, ImageToken type) {
130         
131         try {
132             ByteArrayBody arrayBody = new ByteArrayBody(bytes, ContentType.create(contentType), fileName);
133             List<NameValuePair> pairs = new ArrayList<NameValuePair>();
134             NameValuePair projectTypePair = new NameValuePair("p", String.valueOf(projectType.getIndex()));
135             pairs.add(projectTypePair);
136             NameValuePair typePair = new NameValuePair("type", String.valueOf(type.getIndex()));
137             pairs.add(typePair);
138             String url = CommonConfig.getConfig(ConfigType.UPLOAD_SERVICE_URL, String.class);
139             String status = HttpUtil.postFile(url, arrayBody, token, pairs);
140             UploadImagResponse response = objectMapper.readValue(status, UploadImagResponse.class);
141             return response;
142         } catch (Exception e) {
143             LOGGER.error(e.getMessage(), e);
144         }
145         return null;
146     }
147 
148     /**
149      * 将输入流转为byte数组
150      * @param input
151      * @return
152      * @throws IOException
153      */
154     public static byte[] toByteArray(InputStream input) throws IOException {
155         ByteArrayOutputStream output = new ByteArrayOutputStream();
156         byte[] buffer = new byte[4096];
157         int n = 0;
158         while (-1 != (n = input.read(buffer))) {
159             output.write(buffer, 0, n);
160         }
161         return output.toByteArray();
162     }
163     
164     /**
165      * 根据内容类型判断文件扩展名
166      * @param contentType 内容类型
167      * @return
168      */
169     public static String getFileexpandedName(String contentType) {
170         
171         String fileEndWitsh = "";
172         if ("image/jpeg".equals(contentType)) {
173             fileEndWitsh = ".jpg";
174         } else if ("audio/mpeg".equals(contentType)) {
175             fileEndWitsh = ".mp3";
176         } else if ("audio/amr".equals(contentType)) {
177             fileEndWitsh = ".amr";
178         } else if ("video/mp4".equals(contentType)) {
179             fileEndWitsh = ".mp4";
180         } else if ("video/mpeg4".equals(contentType)) {
181             fileEndWitsh = ".mp4";
182         }
183         return fileEndWitsh;
184     }
185 
186 }