explain ：

（1） The content of this blog ： In the project , Integrated use of Alibaba OSS;

Catalog

One ： stay 【imooc-news-dev-common】 In general engineering ,  Integrating Ali OSS;

1. stay 【imooc-news-dev-common】 In general engineering , Introducing Ali OSS rely on ;

2. stay 【files】 In the document subproject UploaderService Interface ： Define a 【 Based on Ali OSS, How to upload files 】;

additional 1. stay 【files】 Resource files for file services file-dev.properties and file-prod.properties in ： Definition 【 self-created bucket Of Endpoint】、【 self-created bucket The name of 】、【 The directory where you are going to store user avatars 】、【 Can point to this bucket Of url】;

additional 2. stay 【files】 The development of file service “ Get resource file information ” Configuration class ,FileResource Class ： from file-dev.properties or file-prod.properties in , Get attribute value ;

3. stay 【files】 In the document subproject UploaderServiceImpl In the implementation class ： To achieve 【 Based on Ali OSS, How to upload files 】;

4. stay 【files】 Document subproject FileUploaderController Class , To modify 【 Upload files , Interface 】;

5. effect ;

One ： stay 【imooc-news-dev-common】 In general engineering ,  Integrating Ali OSS;

and 【19： The third chapter ： Developing a pass service ：2： In the program , Get through Alibaba cloud SMS service ; Preliminary development 【 Send a text message , Interface 】;】 equally , For the content of the tool nature of this third-party service , We define it in 【common】 In general engineering ;

PS： To use OSS;JDK The version needs to be 1.7 And above ;

1. stay 【imooc-news-dev-common】 In general engineering , Introducing Ali OSS rely on ;

<dependency>
    <groupId>com.aliyun.oss</groupId>
    <artifactId>aliyun-sdk-oss</artifactId>
    <version>3.10.2</version>
</dependency>

（1） For our specific business scenarios ; The way we upload , choice 【 Stream upload , The way 】, Instead of 【 Upload files , The way 】; then , I will choose 【 Streaming upload , How to upload network stream 】;

（2） namely , In our business here , When users upload pictures on the page , You'll get one MultipartFile; obtain MultipartFile after , We can go through MultipartFile Get one InputStream; then , You can use 【 Streaming upload , How to upload network stream 】 Go upload ;

2. stay 【files】 In the document subproject UploaderService Interface ： Define a 【 Based on Ali OSS, How to upload files 】;

    /**
     *  How to upload files （ Based on Ali OSS）
     * @param file： Files from the front end ; then ,Controller When receiving documents , It's using MultipartFile To receive ;
     * @param userId: user id;
     * @param fileExtName： Extension of the file ;
     * @return
     * @throws Exception
     */
    public String uploadOSS(MultipartFile file, String userId, String fileExtName)
            throws Exception;

explain ：

（1） Method definition description ;

additional 1. stay 【files】 Resource files for file services file-dev.properties and file-prod.properties in ： Definition 【 self-created bucket Of Endpoint】、【 self-created bucket The name of 】、【 The directory where you are going to store user avatars 】、【 Can point to this bucket Of url】;

#  Ali OSS in , self-created 【imooc-news-dev-wgy】 This bucket Of endpoint
file.endpoint=oss-cn-shanghai.aliyuncs.com
#  The use of bucket Name ：imooc-news-dev-wgy
file.bucketName=imooc-news-dev-wgy
#  When uploading files , The path of resources ;( Quite so in bucket in , Create different directory structures ; such as , We created image/face This directory , It is used to store user avatars )
file.objectName=image/face
#  Own Ali OSS in ：【 The one I created Bucket Of , name 】+【Endpoint】 The path of ; Through this path , The only Alibaba that can determine itself in the whole network OSS Of Bucket;
file.ossHost=https://imooc-news-dev-wgy.oss-cn-shanghai.aliyuncs.com/

explain ：

（1）Endpoint： self-created bucket Of Endpoint;

          ●  A little like this ： Ali OSS There are servers in many regions ; I'm creating Bucket When , I chose Shanghai , therefore Bucket Of Endpoint Namely 【oss-cn-shanghai.aliyuncs.com】; If you choose Hangzhou ,Bucket Of Endpoint Namely 【oss-cn-hangzhou.aliyuncs.com】;

          ●  therefore , This Endpoint, There are different Alibaba OSS The role of ;

（2）bucketName： self-created bucket Name ;

          ●  I'm creating Bucket When , Its Bucket There is a warning of duplicate names ; therefore , In giving Bucket When you name it , Be careful not to have the same name as others ;

          ●  therefore , Guess blindly ; In the same area （ such as , I chose Shanghai ）, Its Bucket You can't duplicate names ;

          ●  then ,【Endpoint】+【Bucket  name 】 A combination of the two , can （ In Ali OSS in ） The only one to be sure of Bucket;

          ● PS： Ali OSS Medium Bucket, It's the equivalent of Redis One of the Libraries ; Or say , Like the logical space in the database ;

（3）objectName; The reason , To define a objectName, The logic is as follows ：

          ●  We created one Bucket; then , When we upload files later , Will upload to this Bucket in ;

          ●  The files we will upload later include ： The avatars , Article cover, etc ;

          ●  In order to better distinguish these files , Make the classification of these documents clearer ; We want to put different documents , Stored in different folders ;

          ●  therefore , Here we create 【file.objectName=image/face】; namely , The user avatar we uploaded , Will be stored in a 【 Belong to oss-cn-shanghai.aliyuncs.com This Endpoint Of 】、【imooc-news-dev-wgy This Bucket Medium 】、【/image/face】 Under the table of contents ;

（4）ossHost; The reason , To define a ossHost, The logic is as follows ：

          ●  We upload the file to Alibaba OSS after ; This image needs to be accessible elsewhere ; natural , You need the full path of this file ;

          ●  We define here 【file.ossHost=https://imooc-news-dev-wgy.oss-cn-shanghai.aliyuncs.com/】; It is the first half of the full path of the future file ; You can see in this path , In fact, that is 【https】+【Bucket  name 】+【Endpoint】;

additional 2. stay 【files】 The development of file service “ Get resource file information ” Configuration class ,FileResource Class ： from file-dev.properties or file-prod.properties in , Get attribute value ;

3. stay 【files】 In the document subproject UploaderServiceImpl In the implementation class ： To achieve 【 Based on Ali OSS, How to upload files 】;

    /**
     *  How to upload files （ Based on Ali OSS）
     * @param file： Files from the front end ; then ,Controller When receiving documents , It's using MultipartFile To receive ;
     * @param userId: user id;
     * @param fileExtName： Extension of the file ;
     * @return
     * @throws Exception
     */
    @Override
    public String uploadOSS(MultipartFile file, String userId, String fileExtName) throws Exception {

        /**
         * 1.  structure ossClient; The three parameters in turn are ：【 Ali OSS, Created bucket Of Endpoint】、【 Personal Alibaba account Access Key Secret key id】、
         * 【 Personal Alibaba account Access Key The secret key value of the secret key 】;
         */
        OSS ossClient = new OSSClientBuilder()
                .build(fileResource.getEndpoint(),
                        aliyunResource.getAccessKeyId(),
                        aliyunResource.getAccessKeySecret());

        //2.  according to Controller From here MultipartFile（ natural , This MultipartFile, It's from the front end to Controller Layer of ）, obtain InputStream flow ;
        InputStream inputStream = file.getInputStream();

        //3.  utilize 【 front , We generate users id Of , Snowflake algorithm tool class 】, To generate a random string ; As the file name （ Part of ）;
        String fileName = sid.nextShort();
        
        /**
         * 4.  Pieced together resource file path ;
         *  What we put together here is 【image/face/ The user of the currently logged in user id/ File name generated based on snowflake Algorithm . File extension 】;
         *  This means ： We're going back OSS When uploading files , Want to upload the file to Bucket Of image/face/ The user of the currently logged in user id/ Under the table of contents ;
         */
        String myObjectName = fileResource.getObjectName() + "/" + userId + "/"
                + fileName + "." + fileExtName;
        
        /**
         * 5.  Upload files ;
         *  Upload stream ; The three parameters in turn are ：【 Ali OSS, Created bucket Name 】、【 Path to resource file 】、【 File stream 】;
         */
        ossClient.putObject(fileResource.getBucketName(), myObjectName, inputStream);

        // 6.  After uploading , close ossClient;
        ossClient.shutdown();

        // 7.  Put our spliced resource file path , Return to Controller;Controller When you get it , Will continue to splice this path , Get the full path of the file , And then it goes back to the front end ;
        return myObjectName;
    }

explain ：

（1） First , To be in UploaderServiceImpl In the implementation class , Inject three objects ：FileResource、AliyunResource、Sid;

（2） Read notes ;

4. stay 【files】 Document subproject FileUploaderController Class , To modify 【 Upload files , Interface 】;

5. effect ;

（1） First, the whole situation install Look at the whole project ;

（2） then , start-up 【user】 Customer service 、【files】 File service ;

（3） Remember to use SwitchHost Open the virtual domain name mapping 、 start-up Tomcat Run the front-end project ;;

……………………………………………………

（4） then , visit "http://writer.imoocnews.com:8080/imooc-news/writer/accountInfo.html", User information improvement page ; Upload a file with a size no larger than 500kb User's Avatar of ;

        ●  On the front-end browser interface OK Of ;

then , Click on 【 determine 】 after , It also loads new pictures ;

        ●  Back end console , We also printed out the expected log information ;

        ●  then , Look at the front end , Its file path , It's also in line with our expectations ;

        ●  then , Look at Ali OSS; namely , In the future, if there are multiple users , Will be in /image/face/ Under the table of contents , According to different users id, Create different folders , To store the avatar files of different users ;