Springboot Upload and Download file(multiple format) from S3 - spring

Question

Im trying to expose simple rest controller to take multipart file as input and upload to S3 and download API to get file key as input and download the file from S3 and send to FE.
Here this Api should support all standard file formats.
Is there a generic implementation for this as this looks pretty standard feature . I could not find any implementation

Answer 1

Why don't you try Spring Content? It does exactly what you need.
Assuming maven, Spring Boot and Spring Data (let me know if you are using something else):-
pom.xml
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<!-- HSQL -->
<dependency>
<groupId>org.hsqldb</groupId>
<artifactId>hsqldb</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.hateoas</groupId>
<artifactId>spring-hateoas</artifactId>
</dependency>
<dependency>
<groupId>com.github.paulcwarren</groupId>
<artifactId>content-s3-spring-boot-starter</artifactId>
<version>${spring-content-version}</version>
</dependency>
<dependency>
<groupId>com.github.paulcwarren</groupId>
<artifactId>content-rest-spring-boot-starter</artifactId>
<version>${spring-content-version}</version>
</dependency>
...
<dependencies>
Update your entity with the managed Spring Content annotations.
Document.java
#Entity
public class Document {
...existing fields...
#ContentId
private String contentId;
#ContentLength
private Long contentLen;
#MimeType
private String mimeType;
...getters and setters...
}
Create a connection to your S3 store. The S3 Store has been implemented to use a SimpleStorageResourceLoader so this bean will ultimately be used by your store.
StoreConfig.java
#Configuration
#EnableS3Stores
public class S3Config {
#Autowired
private Environment env;
public Region region() {
return Region.getRegion(Regions.fromName(System.getenv("AWS_REGION")));
}
#Bean
public BasicAWSCredentials basicAWSCredentials() {
return new BasicAWSCredentials(env.getProperty("AWS_ACCESS_KEY_ID"), env.getProperty("AWS_SECRET_KEY"));
}
#Bean
public AmazonS3 client(AWSCredentials awsCredentials) {
AmazonS3Client amazonS3Client = new AmazonS3Client(awsCredentials);
amazonS3Client.setRegion(region());
return amazonS3Client;
}
#Bean
public SimpleStorageResourceLoader simpleStorageResourceLoader(AmazonS3 client) {
return new SimpleStorageResourceLoader(client);
}
}
Define a Store typed to Document - as that is what you are associating content with.
DocumentContentStore.java
#StoreRestResource
public interface DocumentStore extends ContentStore<Document, String> {
}
When you run this you also need to set the bucket for your store. This can be done by specifying spring.content.s3.bucket in application.properties/yaml or by setting the AWS_BUCKET environment variable.
This is enough to create a REST-based content service for storing content in S3 and associating that content with your Document entity. Spring Content will see the Store interface and the S3 dependencies. Assume you want to store content in S3 and inject an implementation of your interface for you. Meaning you dont have to implement it yourself. You will be able to store content by POSTing a multipart-form-data request to:
POST /documents/{documentId}/content
and fetching it again with:
GET /documents/{documentId}/content
(the service supports full CRUD BTW and video streaming in case that might be important).
You'll see that Spring Content associates content with your entity by managing the content related annotations for you.
This can be used with or without Spring Data. The dependencies and Store are a little different depending. I assume you have entities that you want to associate data with as you added a spring-data tag but let me know if not and I can adapt the answer.
There is a video of this here - the demo starts about half way through. It uses the Filesystem module not S3 but they are interchangeable. Just need to pick the right dependencies for the type of store you are using. S3 in your case.
HTH