使用jetty和mongodb做个简易文件系统

2024-09-08 07:48
文章标签 使用 mongodb 文件系统 简易 做个 jetty

本文主要是介绍使用jetty和mongodb做个简易文件系统，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

使用jetty和mongodb做个简易文件系统 - ciaos

时间 2014-03-09 21:21:00   博客园-所有随笔区
原文   http://www.cnblogs.com/ciaos/p/3590662.html
主题  MongoDB  Jetty  文件系统

依赖库：

1，jetty（提供http方式接口）

2，mongodb的java驱动（访问mongodb存取文件）

3，thumbnailator包，进行缩略图生成

4，commons-fileupload包及commons-io包用于处理文件上传

入口代码如下：

package com.ciaos.vfs;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.servlet.ServletContextHandler;
import org.eclipse.jetty.servlet.ServletHolder;public class VfsServer {public static void main(String[] args) throws Exception {
   Server server = new Server(8080);     ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS);
   context.setContextPath("/");     server.setHandler(context);     context.addServlet(new ServletHolder(new VfsFileServlet()), "/file");   server.start();
   server.join();}
}

业务代码如下：

package com.ciaos.vfs;import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.UnknownHostException;
import java.util.List;import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;  
import javax.servlet.http.HttpServletRequest;  
import javax.servlet.http.HttpServletResponse;  import net.coobird.thumbnailator.Thumbnails;import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.bson.types.ObjectId;import com.mongodb.DB;
import com.mongodb.Mongo;
import com.mongodb.gridfs.GridFS;
import com.mongodb.gridfs.GridFSDBFile;
import com.mongodb.gridfs.GridFSInputFile;public class VfsFileServlet extends HttpServlet {  /**
   * 
   */
  private static final long serialVersionUID = 5586455171943232770L;
  
  private String tempPath = null;
  private Mongo mongo = null;
  
  final private String MongoDbIp = "192.168.1.106";
  final private Integer MongoDbPort = 27017;
  
  final private String MongoDbName = "chat";
  
  @Override
  public void init() throws ServletException {
    // TODO Auto-generated method stub
    
    tempPath = "uploads/";
    try {
      mongo=new Mongo(MongoDbIp, MongoDbPort);
    } catch (UnknownHostException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
      System.exit(-1);
    }
    super.init();
  }  @Override
  protected void doDelete(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, IOException {
    // TODO Auto-generated method stub
    String fileId = req.getParameter("id");  
    DB db=mongo.getDB(MongoDbName);
    GridFS gridFS=new GridFS(db);
    try{
      gridFS.remove(new ObjectId(fileId));
    }
    catch(IllegalArgumentException ex){
      resp.sendError(404,"file not found");
      return;
    }
  }  @Override
  protected void doGet(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, IOException {
    // TODO Auto-generated method stub
    String fileId = req.getParameter("id");
    
    DB db=mongo.getDB(MongoDbName);
    GridFS gridFS=new GridFS(db);
    
    GridFSDBFile mongofile = null;
    try{
      mongofile = gridFS.find(new ObjectId(fileId));
    }
    catch(IllegalArgumentException ex){
      resp.sendError(404,"file not found");
    }
    
    if(mongofile!=null){
      resp.setHeader("Content-type", "application/octet-stream");
      resp.setHeader("Content-Disposition", "attachment; filename= "+mongofile.getFilename());
      mongofile.put("viewtimes", (Integer)mongofile.get("viewtimes")+1);
      ServletOutputStream out = resp.getOutputStream();
            String dtype = req.getParameter("type");
      if(dtype!=null && dtype.equals("preview")){
        Integer width = 0, height = 0;
        try{
          width = Integer.parseInt(req.getParameter("w"));
          height = Integer.parseInt(req.getParameter("h"));
          Thumbnails.of(mongofile.getInputStream())   
              .size(width, height)  
              .toOutputStream(out);
        }
        catch(NumberFormatException ex){
          resp.sendError(400,"bad request");
          return;
        }
      }else{
        InputStream input = mongofile.getInputStream();
        byte[] buffer = new byte[64*1024];
        for(;;)
        {
          int count = input.read(buffer);
          if (count < 0)
            break;
          out.write(buffer,0,count);
        }
      }      out.flush();
      out.close();
      mongofile.save();
    }else{
      resp.sendError(500,"internal server error");
    }
  }  @Override
  protected void doPost(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, IOException {
    // TODO Auto-generated method stub
    doPut(req, resp);
  }  @Override
  protected void doPut(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, IOException {
    // TODO Auto-generated method stub
    req.setCharacterEncoding("utf-8");
    DiskFileItemFactory factory = new DiskFileItemFactory();
    factory.setRepository(new File(tempPath));
    factory.setSizeThreshold(1024 * 1024);
    ServletFileUpload upload = new ServletFileUpload(factory);
    try {
      List<FileItem> list = (List<FileItem>) upload.parseRequest(req);
      for (FileItem item : list) {
        if (item.isFormField()) {
        } else {
          String value = item.getName();
          int start = value.lastIndexOf("\\");
          String filename = value.substring(start + 1);	
          
          DB db=mongo.getDB(MongoDbName);
          GridFS gridFS=new GridFS(db);
          
          GridFSInputFile  mongofile=gridFS.createFile(item.getInputStream());
          mongofile.put("viewtimes",0);
          
          mongofile.put("filename", filename);
          mongofile.save();
          
          resp.getWriter().println(mongofile);  
          resp.getWriter().flush();  
        }
      }
    } catch (Exception e) {
      e.printStackTrace();
      resp.sendError(500,"internal server error");
    }
  }
}

运行方法（eclipse很简单不用介绍，linux命令行下面不用创建uploads文件夹也可使用）：

javac -cp .:../libs/* com/speakbang/vfs/*.java -Xlint:deprecation
java -cp .:../libs/* com/speakbang/vfs/VfsServer

测试方法：

上传：curl -F "action=upload" -F "Filedata=@a.png" -v "http://127.0.0.1:8080/file"
{ "_id" : { "$oid" : "531c5fe6744e22f4c22eeef5"} , "chunkSize" : 262144 , "length" : 1033834 , "md5" : "04bc7c0988ecc04f93cfa96f239dda99" , "filename" : "a.png" , "contentType" :  null  , "viewtimes" : 0 , "uploadDate" : { "$date" : "2014-03-09T12:34:46.347Z"} , "aliases" :  null }
下载：curl -o /dev/null -v http://127.0.0.1:8080/file?id=531c5fe6744e22f4c22eeef5&type=preview&w=200&h=200

删除:curl -X DELETE -v "http://127.0.0.1:8080/file?id=531c5fe6744e22f4c22eeef5"




第二个类似的参考文档：
使用jetty和mongodb实现简易网盘接口
依赖库：
1，jetty（提供http方式接口）
2，mongodb的java驱动（访问mongodb存取文件）
3，thumbnailator包，进行缩略图生成
4，commons-fileupload包及commons-io包用于处理文件上传
架构图：
入口代码如下：
复制代码
package com.ciaos.vfs;
import org.eclipse.jetty.server.Connector;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.server.nio.SelectChannelConnector;
import org.eclipse.jetty.servlet.ServletContextHandler;
import org.eclipse.jetty.servlet.ServletHolder;
import org.eclipse.jetty.util.thread.QueuedThreadPool;public class VfsServer {public static void main(String[] args) throws Exception {SelectChannelConnector connector = new SelectChannelConnector();connector.setHost("127.0.0.1");connector.setPort(8080);connector.setThreadPool(new QueuedThreadPool(200));Server server = new Server();  server.setConnectors(new Connector[]{connector}); ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS);context.setContextPath("/");  server.setHandler(context);  context.addServlet(new ServletHolder(new VfsFileServlet()), "/file");server.start();server.join();}
}
复制代码
业务代码如下：
复制代码
package com.ciaos.vfs;import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.UnknownHostException;
import java.util.List;import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;  
import javax.servlet.http.HttpServletRequest;  
import javax.servlet.http.HttpServletResponse;  import net.coobird.thumbnailator.Thumbnails;import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.bson.types.ObjectId;import com.mongodb.DB;
import com.mongodb.Mongo;
import com.mongodb.gridfs.GridFS;
import com.mongodb.gridfs.GridFSDBFile;
import com.mongodb.gridfs.GridFSInputFile;public class VfsFileServlet extends HttpServlet {/*** */private static final long serialVersionUID = 5586455171943232770L;private String tempPath = null;private Mongo mongo = null;final private String MongoDbIp = "127.0.0.1";final private Integer MongoDbPort = 27017;@Overridepublic void init() throws ServletException {// TODO Auto-generated method stub
        tempPath = "/tmp/";try {mongo=new Mongo(MongoDbIp, MongoDbPort);} catch (UnknownHostException e) {// TODO Auto-generated catch block
            e.printStackTrace();System.exit(-1);}super.init();}@Overrideprotected void doDelete(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {// TODO Auto-generated method stubString fileId = req.getParameter("id");String MongoDbName = req.getParameter("type");if(fileId == null || MongoDbName == null){resp.sendError(400,"bad request");return;}DB db=mongo.getDB(MongoDbName);GridFS gridFS=new GridFS(db);try{gridFS.remove(new ObjectId(fileId));}catch(IllegalArgumentException ex){resp.sendError(404,"file not found");return;}}@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {// TODO Auto-generated method stubString fileId = req.getParameter("id");String MongoDbName = req.getParameter("type");if(fileId == null || MongoDbName == null){resp.sendError(400,"bad request");return;}DB db=mongo.getDB(MongoDbName);GridFS gridFS=new GridFS(db);GridFSDBFile mongofile = null;try{mongofile = gridFS.find(new ObjectId(fileId));}catch(IllegalArgumentException ex){resp.sendError(404,"file not found");return;}if(mongofile!=null){resp.setHeader("Content-type", mongofile.getContentType());resp.setHeader("Content-Disposition", "attachment; filename= "+mongofile.getFilename());mongofile.put("viewtimes", (Integer)mongofile.get("viewtimes")+1);ServletOutputStream out = resp.getOutputStream();String dtype = req.getParameter("act");if(dtype!=null && dtype.equals("preview")){Integer width = 0, height = 0;try{width = Integer.parseInt(req.getParameter("w"));height = Integer.parseInt(req.getParameter("h"));BufferedImage image = ImageIO.read(mongofile.getInputStream());width = Math.min(width,image.getWidth());height = Math.min(height,image.getHeight());Thumbnails.of(mongofile.getInputStream())   .size(width, height)  .toOutputStream(out);}catch(NumberFormatException ex){resp.sendError(400,"bad request");return;}}else{InputStream input = mongofile.getInputStream();byte[] buffer = new byte[64*1024];for(;;){int count = input.read(buffer);if (count < 0)break;out.write(buffer,0,count);}}out.flush();out.close();mongofile.save();}else{resp.sendError(500,"internal server error");}}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {// TODO Auto-generated method stub
        doPut(req, resp);}@Overrideprotected void doPut(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {// TODO Auto-generated method stubreq.setCharacterEncoding("utf-8");DiskFileItemFactory factory = new DiskFileItemFactory();factory.setRepository(new File(tempPath));factory.setSizeThreshold(8 * 1024 * 1024);ServletFileUpload upload = new ServletFileUpload(factory);try {List<FileItem> list = (List<FileItem>) upload.parseRequest(req);for (FileItem item : list) {if (item.isFormField()) {} else {String value = item.getName();int start = value.lastIndexOf("\\");String filename = value.substring(start + 1);    String MongoDbName = req.getParameter("type");if(MongoDbName == null){resp.sendError(400,"bad request");return;}DB db=mongo.getDB(MongoDbName);GridFS gridFS=new GridFS(db);GridFSInputFile  mongofile=gridFS.createFile(item.getInputStream());mongofile.put("viewtimes",0);mongofile.setContentType(item.getContentType());mongofile.put("filename", filename);mongofile.save();resp.getWriter().println(mongofile);  resp.getWriter().flush();  }}} catch (Exception e) {e.printStackTrace();resp.sendError(500,"internal server error");}}
}
复制代码
运行方法一（eclipse很简单不用介绍，linux命令行运行方法，大于8M文件通过/tmp/目录缓存）：
javac -cp .:../libs/* com/speakbang/vfs/*.java -Xlint:deprecation
java -cp .:../libs/* com/speakbang/vfs/VfsServer
运行方法二（只需要VfsFileServlet.java，集成到jetty配置文件）
复制代码
root:~/jetty/webapps # ls -R *
ROOT:WEB-INFclassescom/ciaos/vfs/VfsFileServlet.classlibcommons-fileupload-1.3.1.jar  commons-io-2.4.jar  mongo-java-driver-2.11.4.jar  thumbnailator-0.4.7.jarsrccom/ciaos/vfs/VfsFileServlet.javaweb.xml
复制代码
web.xml
复制代码
<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"version="2.5"><servlet><servlet-name>VfsServlet</servlet-name><servlet-class>com.ciaos.vfs.VfsFileServlet</servlet-class><load-on-startup>0</load-on-startup></servlet><servlet-mapping><servlet-name>VfsServlet</servlet-name><url-pattern>/file</url-pattern></servlet-mapping>
</web-app>
复制代码
cd webapps/ROOT/WEB-INF/src/
javac -cp .:../lib/*:../../../../lib/* com/ciaos/vfs/VfsFileServlet.java -Xlint:deprecation
mv com/ciaos/vfs/VfsFileServlet.class ../classes/com/ciaos/vfs/
cd ../../../../
java -jar start.jar -Xms128m -Xmx256m
(bin/jetty.sh start|restart|stop)
运行方法三（将class文件打成jar包，放到lib目录下，可以不用放置src和classes目录及源码了）
复制代码
cd classes/
jar cvf vfs.jar com
cd ..
mv classes/vfs.jar lib/
rm -rf classes src
cd ../../
java -jar start.jar
复制代码
注意文件不能直接操作db.fs.files.remove()删除，fs.chunks这个collection里面才是包含文件内容的，正确的删除方法使用如下脚本或者调用DELETE接口，删除完毕后用db.repairDatabase()释放磁盘空间：
复制代码
var year=2014
var month=3
var day=15use testvar items = db.fs.files.find({uploadDate:{$lte:new Date(year+"/"+month+"/"+day)}})
items.forEach(function(item) {db.fs.chunks.remove({files_id: item._id})db.fs.files.remove({_id:item._id})print(item._id + " deleted")
})//运行方法： bin/mongo < tool/delete.js
//root:~/mongodb$ bin/mongo < tool/delete.js
//MongoDB shell version: 2.4.9
//connecting to: test
//switched to db test
//532259170cf2c0bcb68e1e72 deleted
//532259190cf2c0bcb68e1e76 deleted
//5322591a0cf2c0bcb68e1e7a deleted
//bye
复制代码
使用方法：
 
上传：curl -F "action=upload" -F "Filedata=@a.png;type=image/png" -v "http://127.0.0.1:8080/file?type=test"
{ "_id" : { "$oid" : "531c5fe6744e22f4c22eeef5"} , "chunkSize" : 262144 , "length" : 1033834 , "md5" : "04bc7c0988ecc04f93cfa96f239dda99" , "filename" : "a.png" , "contentType" :  null  , "viewtimes" : 0 , "uploadDate" : { "$date" : "2014-03-09T12:34:46.347Z"} , "aliases" :  null }
下载：curl -o /dev/null -v http://127.0.0.1:8080/file?type=test&id=531c5fe6744e22f4c22eeef5&act=preview&w=200&h=200
删除:curl -X DELETE -v "http://127.0.0.1:8080/file?type=test&id=531c5fe6744e22f4c22eeef5"
 
Java代码上传方法（支持多文件上传）
复制代码
package com.test;import java.io.BufferedReader;import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.List;/*** This utility class provides an abstraction layer for sending multipart HTTP* POST requests to a web server.* @author www.codejava.net**/
public class MultipartUtility {private final String boundary;private static final String LINE_FEED = "\r\n";private HttpURLConnection httpConn;private String charset;private OutputStream outputStream;private PrintWriter writer;/*** This constructor initializes a new HTTP POST request with content type* is set to multipart/form-data* @param requestURL* @param charset* @throws IOException*/public MultipartUtility(String requestURL, String charset)throws IOException {this.charset = charset;// creates a unique boundary based on time stampboundary = "===" + System.currentTimeMillis() + "===";URL url = new URL(requestURL);httpConn = (HttpURLConnection) url.openConnection();httpConn.setUseCaches(false);httpConn.setDoOutput(true); // indicates POST methodhttpConn.setDoInput(true);httpConn.setRequestProperty("Content-Type","multipart/form-data; boundary=" + boundary);outputStream = httpConn.getOutputStream();writer = new PrintWriter(new OutputStreamWriter(outputStream, charset),true);}/*** Adds a form field to the request* @param name field name* @param value field value*/public void addFormField(String name, String value) {writer.append("--" + boundary).append(LINE_FEED);writer.append("Content-Disposition: form-data; name=\"" + name + "\"").append(LINE_FEED);writer.append("Content-Type: text/plain; charset=" + charset).append(LINE_FEED);writer.append(LINE_FEED);writer.append(value).append(LINE_FEED);writer.flush();}/*** Adds a upload file section to the request* @param fieldName name attribute in <input type="file" name="..." />* @param uploadFile a File to be uploaded* @throws IOException*/public void addFilePart(String fieldName, File uploadFile)throws IOException {String fileName = uploadFile.getName();writer.append("--" + boundary).append(LINE_FEED);writer.append("Content-Disposition: form-data; name=\"" + fieldName+ "\"; filename=\"" + fileName + "\"").append(LINE_FEED);writer.append("Content-Type: "+ URLConnection.guessContentTypeFromName(fileName)).append(LINE_FEED);writer.append("Content-Transfer-Encoding: binary").append(LINE_FEED);writer.append(LINE_FEED);writer.flush();FileInputStream inputStream = new FileInputStream(uploadFile);byte[] buffer = new byte[4096];int bytesRead = -1;while ((bytesRead = inputStream.read(buffer)) != -1) {outputStream.write(buffer, 0, bytesRead);}outputStream.flush();inputStream.close();writer.append(LINE_FEED);writer.flush();    }/*** Adds a header field to the request.* @param name - name of the header field* @param value - value of the header field*/public void addHeaderField(String name, String value) {writer.append(name + ": " + value).append(LINE_FEED);writer.flush();}/*** Completes the request and receives response from the server.* @return a list of Strings as response in case the server returned* status OK, otherwise an exception is thrown.* @throws IOException*/public List<String> finish() throws IOException {List<String> response = new ArrayList<String>();writer.append(LINE_FEED).flush();writer.append("--" + boundary + "--").append(LINE_FEED);writer.close();// checks server's status code firstint status = httpConn.getResponseCode();if (status == HttpURLConnection.HTTP_OK) {BufferedReader reader = new BufferedReader(new InputStreamReader(httpConn.getInputStream()));String line = null;while ((line = reader.readLine()) != null) {response.add(line);}reader.close();httpConn.disconnect();} else {throw new IOException("Server returned non-OK status: " + status);}return response;}public static void main(String[] args) {String charset = "UTF-8";File uploadFile1 = new File("c:/1.jpg");File uploadFile2 = new File("c:/2.jpg");String requestURL = "http://localhost:8080/file?type=test";try {MultipartUtility multipart = new MultipartUtility(requestURL, charset);
/*             multipart.addHeaderField("User-Agent", "CodeJava");multipart.addHeaderField("Test-Header", "Header-Value");multipart.addFormField("description", "Cool Pictures");multipart.addFormField("keywords", "Java,upload,Spring");
*/             multipart.addFilePart("fileUpload", uploadFile1);multipart.addFilePart("fileUpload", uploadFile2);List<String> response = multipart.finish();for (String line : response) {System.out.println(line);}//output//533e27560cf2f5c3e3d77748//533e27560cf2f5c3e3d7774a
            } catch (IOException ex) {System.err.println(ex);}}
}
复制代码


1.http://www.tuicool.com/articles/YBZj2i
2.http://www.cnblogs.com/ciaos/p/3590662.html


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