本期简介
文件上传是非常常见的功能,本期要实现的功能是将文件存储到阿里云分布式对象存储OSS中,这样做的好处是随便哪里都可以方便的展示出该图片,并且图片以链接形式在客户端浏览器渲染,流量不会经过后台,降低后台压力,但若对文件有限制性的操作,还是要通过后台返回文件
- 本期要点:
- 配置阿里云OSS密钥
- 编写OSS上传的简单类
- Springboot集成OSS
- 后端开发上传接口
- 前端开发Vue+Iview+Uploader组件
- 前端渲染上传后的图片
一、配置阿里云OSS密钥及桶
1、购买链接
如果没有云存储,可访问阿里云官网,搜索对象存储或者访问下方链接,按需购买
https://common-buy.aliyun.com/?spm=5176.7933691.J_5253785160.2.64e62c47OY978E&commodityCode=oss_rc_dp_cn
2、创建桶
对象存储是以桶来进行文件管理,文件都存在一个个的桶里,每个桶可以存放目录和文件,即可以按照文件进行分类存储,可以创建多个桶。
从下图可以看到,一个桶里面可以存储多个文件夹,文件夹里可以存多个文件,桶里面也可以直接存文件
二、配置密钥
要想将文件上传到OSS中,用的是AK/SK的方式进行认证授权,所以需要先在阿里云OSS中配置安全密钥,
-
点击头像打开访问控制页面
-
创建用户
-
创建访问AccessKey
需要注意的是,创建的时候AppSecret及时复制出来保存,关闭弹窗后,无法再从阿里云页面找到,若不慎丢失,需重新生成
至此,云存储已经具备了,访问的AK/SK也有了,接下来编写客户端上传下载的逻辑。
三、编写OSS上传的简单类
1、将AK、SK配置到环境变量
2、添加maven依赖
<dependency><groupId>com.aliyun.oss</groupId><artifactId>aliyun-sdk-oss</artifactId><version>3.15.1</version></dependency>
3、初始化OSS配置
- 配置类
public class OssConfig {private String accessKeyId;private String secretAccessKey;private String endpoint;private String bucketName;
}
- 初始化OSS
private final DefaultCredentialProvider credentialsProvider;private final OssConfig ossConfig;@SneakyThrowspublic OssHelper(@Autowired OssConfig ossConfig) {// 从环境变量中获取访问凭证。运行本代码示例之前,请先配置环境变量。if (ossConfig == null) {throw new ServerException("初始化对象存储工具失败,配置信息未读取到");}this.ossConfig = ossConfig;this.credentialsProvider = CredentialsProviderFactory.newDefaultCredentialProvider(ossConfig.getAccessKeyId(), ossConfig.getSecretAccessKey());}
3、上传方法
OSS支持上传的类型非常多,这里例举几类
- 上传本地二进制文件
public Optional<String> upload(File file, String ossDir, String ossFileName) {try {return this.uploadToOss(file, ossDir, ossFileName);} catch (Exception exception) {log.error("上传字符串前异常:{}", exception.getMessage());}return Optional.empty();}
- 上传文本
public Optional<String> upload(String content, String ossDir, String ossFileName) {try {InputStream inputStream = new ByteArrayInputStream(content.getBytes(StandardCharsets.UTF_8));return this.uploadToOss(inputStream, ossDir, ossFileName);} catch (Exception exception) {log.error("上传字符串前异常:{}", exception.getMessage());}return Optional.empty();}
- 上传字节类
public Optional<String> upload(byte[] content, String ossDir, String ossFileName) {try {InputStream inputStream = new ByteArrayInputStream(content);return this.uploadToOss(inputStream, ossDir, ossFileName);} catch (Exception exception) {log.error("上传字符串前异常:{}", exception.getMessage());}return Optional.empty();}
- 上传网络资源
public Optional<String> upload(URL url, String ossDir, String ossFileName) {try {if (url == null) {return Optional.empty();}InputStream inputStream = url.openStream();return this.uploadToOss(inputStream, ossDir, ossFileName);} catch (Exception exception) {log.error("上传字符串前异常:{}", exception.getMessage());}return Optional.empty();}
- 上传核心业务逻辑
private Optional<String> uploadToOss(Object object, String ossDir, String ossFileName) {// 填写Object完整路径,例如exampledir/exampleobject.txt。Object完整路径中不能包含Bucket名称。OSS ossClient = new OSSClientBuilder().build(ossConfig.getEndpoint(), credentialsProvider);try {String objectName = getObjectName(ossDir, ossFileName);PutObjectRequest putObjectRequest = null;if (object instanceof InputStream) {putObjectRequest = new PutObjectRequest(ossConfig.getBucketName(), objectName, (InputStream) object);}if (object instanceof File) {putObjectRequest = new PutObjectRequest(ossConfig.getBucketName(), objectName, (InputStream) object);}if (putObjectRequest == null) {return Optional.empty();}PutObjectResult result = ossClient.putObject(putObjectRequest);// 设置签名URL过期时间,单位为毫秒。本示例以设置过期时间为50年为例。Date expiration = new Date(new Date().getTime() + 50 * 365 * 24 * 3600 * 1000L);// 生成以GET方法访问的签名URL,访客可以直接通过浏览器访问相关内容。URL url = ossClient.generatePresignedUrl(ossConfig.getBucketName(), objectName, expiration);if (url != null) {return Optional.of(url.toString());}return Optional.empty();} catch (OSSException oe) {log.error("Caught an OSSException, which means your request made it to OSS, "+ "but was rejected with an error response for some reason.");log.error("Error Message:" + oe.getErrorMessage());log.error("Error Code:" + oe.getErrorCode());log.error("Request ID:" + oe.getRequestId());log.error("Host ID:" + oe.getHostId());} catch (ClientException ce) {log.error("Caught an ClientException, which means the client encountered "+ "a serious internal problem while trying to communicate with OSS, "+ "such as not being able to access the network.");log.error("Error Message:" + ce.getMessage());} finally {if (ossClient != null) {ossClient.shutdown();}}return Optional.empty();}
4、测试上传与验证
从下图可以看到,成功把字符串hello world
上传到了OSS的certificate目录下,文件名为test.txt
查看OSS桶的对应文件内容,与上传一致
5、下载方法
public void download(String ossDir, String ossFileName) {String objectName = getObjectName(ossDir, ossFileName);// 创建OSSClient实例。OSS ossClient = new OSSClientBuilder().build(ossConfig.getEndpoint(), credentialsProvider);try {// 调用ossClient.getObject返回一个OSSObject实例,该实例包含文件内容及文件元信息。OSSObject ossObject = ossClient.getObject(ossConfig.getBucketName(), objectName);// 调用ossObject.getObjectContent获取文件输入流,可读取此输入流获取其内容。InputStream content = ossObject.getObjectContent();if (content != null) {BufferedReader reader = new BufferedReader(new InputStreamReader(content));while (true) {String line = reader.readLine();if (line == null) {break;}System.out.println("\n" + line);}// 数据读取完成后,获取的流必须关闭,否则会造成连接泄漏,导致请求无连接可用,程序无法正常工作。content.close();}} catch (OSSException oe) {System.out.println("Caught an OSSException, which means your request made it to OSS, "+ "but was rejected with an error response for some reason.");System.out.println("Error Message:" + oe.getErrorMessage());System.out.println("Error Code:" + oe.getErrorCode());System.out.println("Request ID:" + oe.getRequestId());System.out.println("Host ID:" + oe.getHostId());} catch (ClientException ce) {System.out.println("Caught an ClientException, which means the client encountered "+ "a serious internal problem while trying to communicate with OSS, "+ "such as not being able to access the network.");System.out.println("Error Message:" + ce.getMessage());} finally {if (ossClient != null) {ossClient.shutdown();}}}
6、测试下载与验证
从OSS中将前面上传的test.txt下载下来打印出内容,与上传时的一致
四、springboot集成OSS
到了这一步,上传、下载等功能已经具备了,只需要将其与Springboot集成起来,即可在各个业务中使用,为了使用单例模式,这里将其注册为Spring Bean
1、配置类
@Data
@Configuration
@ConfigurationProperties(prefix = "aliyun.oss")
public class OssConfig {private String accessKeyId;private String secretAccessKey;private String endpoint;private String bucketName;
}
2、application.yml配置
3、OSS核心类
@Slf4j
@Component
public class OssHelper {private final DefaultCredentialProvider credentialsProvider;private final OssConfig ossConfig;@SneakyThrowspublic OssHelper(@Autowired OssConfig ossConfig) {// 从环境变量中获取访问凭证。运行本代码示例之前,请先配置环境变量。if (ossConfig == null) {throw new ServerException("初始化对象存储工具失败,配置信息未读取到");}this.ossConfig = ossConfig;this.credentialsProvider = CredentialsProviderFactory.newDefaultCredentialProvider(ossConfig.getAccessKeyId(), ossConfig.getSecretAccessKey());}public Optional<String> upload(File file, String ossDir, String ossFileName) {.........}public Optional<String> upload(String content, String ossDir, String ossFileName) {...........}public Optional<String> upload(byte[] content, String ossDir, String ossFileName) {............}public Optional<String> upload(URL url, String ossDir, String ossFileName) {............}private Optional<String> uploadToOss(Object object, String ossDir, String ossFileName) {............}public void download(String ossDir, String ossFileName) {............}
}
五、后端开发上传逻辑
1、编写接口,入参只有一个MultipartFile
2、上传逻辑
这里是直接获取到MultipartFile的字节数组,将其上传到OSStest/cover
目录下,文件名是通过雪花算法生成的id
至此,后端已经具备文件上传的完整功能,接下来编写前端的上传功能
六、前端开发Vue+Iview+Uploader组件
1、使用Iview Uploader
该组件可以支持拖拽和选择上传,功能方便,实现简单
<FormItem label="封面" prop="coverId"><Uploadref="upload":show-upload-list="false":format="['zip','png','jpg','jpeg','pdf','doc','docx','ppt','pptx','xls','xlsx']":max-size="5120":on-success="handleUploadSuccess":on-error="handleUploadFailed":on-format-error="handleFormatError":on-exceeded-size="handleMaxSize":before-upload="handleBeforeUpload"style="width: 210px;height:50px;"type="drag":action="albumCoverAction":headers="uploadHeader"><div><Icon type="ios-cloud-upload" size="30" style="color: #3399ff"></Icon><p>点击上传或将图片拖拽到这里</p></div></Upload><RadioGroup v-model="formData.coverId"><Row style="margin-top: 40px;margin-left: 0px;"><Col span="4"><div><Card dis-hover style="height:auto;width:210px;"><p slot="title">自定义封面</p><Row><Col span="24"><Radio :label="customCover.id"><div :class="selectedCover===customCover.id?'album-cover-selected':'album-cover'"@click="changeCover(customCover)"style="margin-right: 10px;"><img :src="customCover.coverUrl"/></div></Radio></Col></Row></Card></div></Col><Col span="19" offset="1"><Card dis-hover style="height:auto"><p slot="title">系统默认封面</p><Row><Col span="24"><Radio v-for="(item, index) in $store.state.defaultAlbumCovers" class="cover-default":key="index":label="item.id"><div :class="selectedCover===item.id?'album-cover-selected':'album-cover'"@click="changeCover(item)"style="margin-right: 5px;"><img :src="item.coverUrl"/></div></Radio></Col></Row></Card></Col></Row></RadioGroup></FormItem>
2、上传地址和鉴权
上面的上传组件中的文件往哪里上传,以及怎么通过后端的用户登录认证,是通过如下2个值来决定的