Mongodb GridFS中对文件的上传、下载、删除
写在前面
因为公司之前电商系统的图片存储用的是mongodb，所以昨天讨论后把原定的fastfds改用为mongodb的gridfs。 mongodb的分片机制也是高可用，高可扩展的。
原文章地址
mongoDb3.2 api地址
示例
maven 依赖
<dependency>
<groupId>org.mongodbgroupId>
<artifactId>mongo-java-driverartifactId>
<version>3.2.2version>
dependency>
代码示例
- 工具类
package com.yjy.dg.app.log.mongo;
import com.mongodb.MongoClient;
import com.mongodb.MongoClientOptions;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.MongoDatabase;
import com.mongodb.client.gridfs.GridFSBucket;
import com.mongodb.client.gridfs.GridFSBuckets;
import com.mongodb.client.gridfs.GridFSDownloadStream;
import com.mongodb.client.gridfs.model.GridFSFile;
import com.yjy.dg.app.log.utils.CommonUtil;
import org.bson.types.ObjectId;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.*;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import java.util.UUID;
import java.util.regex.Pattern;
/**
* MongoDbUtil use mongo-java-driver-3.2.2 gridfs
* @author littlehow * @time 2016-07-19 9:18
*/
public class MongoDbUtil {
private MongoDbUtil(){}
private final static Properties properties = new Properties();
private static Logger log = LoggerFactory.getLogger(MongoDbUtil.class);
static {
try {
URL url = MongoDbUtil.class.getClassLoader().getResource("mongo_db.properties");
if (url != null) {
log.info("Found 'mongo_db.properties' file in local classpath");
InputStream in = url.openStream();
try {
properties.load(in);
} finally {
in.close();
}
}
} catch (IOException e) {
log.info("Could not load 'mongo_db.properties' file from local classpath: " + e);
}
}
/** * config file info */
private static class Config {
//mongodb connection properties
public static String ip = null;
public static int port = 27017;//default port is 27017
public static String database = null; //mongodb connection pool properties public static int connectionsPerHost = 10;
public static int maxWaitTime = 120000;
public static int connectTimeout = 0;
public static MongoClientOptions options = null; //author public static List credential = new ArrayList<>();
static {
ip = properties.getProperty("mongo_ip");
database = properties.getProperty("mongo_database");
int _port = CommonUtil.getIntValue(properties.getProperty("mongo_port"));
if (_port != -1) port = _port;
int _conn = CommonUtil.getIntValue(properties.getProperty("connections_per_host"));
if (_conn != -1) connectionsPerHost = _conn;
int _waittime = CommonUtil.getIntValue(properties.getProperty("max_wait_time"));
if (_waittime != -1) maxWaitTime = _waittime;
int _timeout = CommonUtil.getIntValue(properties.getProperty("connect_timeout"));
if (_timeout != -1) connectTimeout = _timeout;
options = MongoClientOptions.builder()
.connectTimeout(connectTimeout)
.maxWaitTime(maxWaitTime)
.connectionsPerHost(connectionsPerHost).build();
MongoCredential credential1 = MongoCredential.createCredential(properties.getProperty("mongo_user"), database, properties.getProperty("mongo_pass").toCharArray());
credential.add(credential1);
}
}
private static final class MongoInstance {
public final static MongoClient client;
static {
client = new MongoClient(new ServerAddress(Config.ip, Config.port), Config.credential, Config.options);
}
}
/**
* destroy pool
*/
public static final void destroy() {
MongoInstance.client.close();
}
/**
* get a MongoDatabase
* @return
*/
public static MongoDatabase getDatabase() {
return MongoInstance.client.getDatabase(Config.database);
}
/**
* get a MongoDatabase by Name
* @param databaseName
* @return
*/
public static MongoDatabase getDatabase(String databaseName) {
return MongoInstance.client.getDatabase(databaseName);
}
/**
* upload file to mongo
* @param filename
* @param in
* @return
*/
public static String uploadFileToGridFS(String filename, InputStream in) {
//default bucket name is fs
GridFSBucket bucket = GridFSBuckets.create(getDatabase());
ObjectId fileId = bucket.uploadFromStream(filename, in);
return fileId.toHexString();
}
/**
* upload file to mongo, if close is true then close the inputstream
* @param filename
* @param in
* @param close
* @return
*/
public static String uploadFileToGridFS(String filename, InputStream in, boolean close) {
String returnId = null;
try {
returnId = uploadFileToGridFS(filename, in);
} finally {
if (close) {
try {
in.close();
} catch (IOException e) {
log.info("close inputstream fail:" + e);
}
}
}
return returnId;
}
/**
* upload file to mongo
* @param fileName
* @param file
* @return
*/
public static String uploadFileToGridFs(String fileName, File file) {
InputStream in = null;
try {
in = new FileInputStream(file);
String returnId = uploadFileToGridFS(fileName, in, true);
return returnId;
} catch (IOException e) {
log.info("upload fail:" + e);
}
return null;
}
/**
* set filename = file name
* @param file
* @return
*/
public static String uploadFileToGridFs(File file) {
return uploadFileToGridFs(file.getName(), file);
}
/**
* set filename = uuid
* @param file
* @return
*/
public static String uploadFileToGridFSByUUID(File file) {
return uploadFileToGridFs(UUID.randomUUID().toString(), file);
}
/**
* download file for gridfs by objectid
* @param objectId
* @param out
*/
public static void downloadFile(String objectId, OutputStream out) {
GridFSBucket bucket = GridFSBuckets.create(getDatabase());
bucket.downloadToStream(new ObjectId(objectId), out);
}
/**
* download file for gridfs by objectid
* @param objectId
* @param file
*/
public static void downloadFile(String objectId, File file) {
OutputStream os = null;
try {
os = new FileOutputStream(file);
downloadFile(objectId, os);
} catch (IOException e) {
log.info("download fail:" + e);
} finally {
if (os != null) {
try { os.close();
} catch (IOException e) {
log.info("close outputstream fail:" + e);
}
}
}
}
/**
* download file for gridfs by objectid
* @param objectId
* @param filename
*/
public static void downloadFile(String objectId, String filename) {
File file = new File(filename);
downloadFile(objectId, file);
}
/**
* download file for gridfs by filename
* @param filename
* @param out
*/
public static void downloadFileByName(String filename, OutputStream out) {
GridFSBucket bucket = GridFSBuckets.create(getDatabase());
bucket.downloadToStreamByName(filename, out);
}
/**
* download file for gridfs use stream
* 如果一次性读取所有字节，大于chunk size的可能会出现乱序，导致文件损坏
* @param objectId
* @param out
*/
public static void downloadFileUseStream(String objectId, OutputStream out) {
GridFSBucket bucket = GridFSBuckets.create(getDatabase());
GridFSDownloadStream stream = null;
try {
stream = bucket.openDownloadStream(new ObjectId(objectId));
/** gridfs file */
GridFSFile file = stream.getGridFSFile();
/** chunk size */
int size = file.getChunkSize();
int len = (int)file.getLength();
/** loop time */
int cnt = len / size + (len % size == 0 ? 0 : 1);
byte[] bts = new byte[Math.min(len, size)];
try {
while (cnt-- > 0) {
int tmp = stream.read(bts);
out.write(bts, 0, tmp);
}
out.flush();
} catch (IOException e) {
log.info("download fail:");
}
} finally {
if (stream != null) stream.close();
}
}
/**
* download file for gridfs use stream
* @param objectId
* @param fileName
*/
public static void downloadFileUseStream(String objectId, String fileName) {
File file = new File(fileName);
downloadFileUseStream(objectId, file);
}
/**
* download file for gridfs use stream
* @param objectId
* @param file
*/
public static void downloadFileUseStream(String objectId, File file) {
OutputStream os = null;
try {
os = new FileOutputStream(file);
downloadFileUseStream(objectId, os);
} catch (IOException e) {
log.info("download fail:" + e);
} finally {
if (os != null) {
try {
os.close();
} catch (IOException e) {
// skip
}
}
}
}
/**
* 将mongo gridfs的文件下载到内存
* @param objectId
* @return
*/
public static byte[] downloadFileUseStream(String objectId) {
GridFSBucket bucket = GridFSBuckets.create(getDatabase());
GridFSDownloadStream stream = null;
try {
stream = bucket.openDownloadStream(new ObjectId(objectId));
/** gridfs file */
GridFSFile file = stream.getGridFSFile();
/** chunk size */
int size = file.getChunkSize();
int len = (int)file.getLength();
int readSize = Math.min(len, size);
byte[] returnBts = new byte[len];
/** offset num */
int offset = 0; while (len > 0) {
int tmp;
if (len > readSize) {
tmp = stream.read(returnBts, offset, readSize);
offset += tmp;
} else {
tmp = stream.read(returnBts, offset, len);
} len -= tmp;
}
return returnBts;
} finally {
if (stream != null) stream.close();
}
}
/**
* delete file from gridfs by objectId
* @param objectId
*/
public static void deleteByObjectId(String objectId) {
GridFSBucket bucket = GridFSBuckets.create(getDatabase());
bucket.delete(new ObjectId(objectId));
}
}
- 调用示例
package littlehow.test;
import littlehow.utils.MongoDbUtil;
import java.io.File;
/**
* MongoDbTest
*
* @author littlehow
* @time 2016-07-19 15:13
*/
public class MongoDbTest {
public static void main(String[] args) {
// upload();
// download();
delete();
}
/**
* 先上传
*/
public static void upload() {
File file = new File("E:\\before\\myself.zip");
String objectId = MongoDbUtil.uploadFileToGridFSByUUID(file);
System.out.println(objectId);//578dccf8b585d81928e6ba62
}
/**
* 再测试下载
*/
public static void download() {
File file = new File("C:\\Users\\Administrator\\Desktop\\linshi\\new.zip");
MongoDbUtil.downloadFile("578dccf8b585d81928e6ba62", file);
}
/**
* 最后将上传的信息删除
*/
public static void delete() {
MongoDbUtil.deleteByObjectId("578dccf8b585d81928e6ba62");
}
}