Deploy kkfileviewer with Docker and Integrate MinIO in Spring Boot

1. Install kkfileviewer container

1.1 Download files

Use kkfileviewer 4.4.0‑beta; clone the repository from the provided URL.

git clone https://codeup.aliyun.com/6254dee9a923b68581caaf50/kkfileviewer.git
cd kkfileviewer
docker build -t kkfileview:v4.4.0 .

1.3 Start kkfileviewer

docker run -d -p 8012:8012 --name kkfileview kkfileview:v4.4.0

1.4 Test access

Open http://your-ip:8012 in a browser to verify the service.

2. Spring Boot integration with MinIO

2.1 Add Maven dependency

<dependency>
    <groupId>io.minio</groupId>
    <artifactId>minio</artifactId>
    <version>8.5.11</version>
</dependency>

2.2 Configuration

# minio file storage configuration
minio:
  endpoint: http://xxxxx:9000
  accessKey: xxxx
  secretKey: xxxxx
  bucketName: test

2.3 MinIO configuration class

package com.sunny.config;

import io.minio.MinioClient;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MinioConfig {
    @Value("${minio.endpoint}") private String endPoint;
    @Value("${minio.accessKey}") private String accessKey;
    @Value("${minio.secretKey}") private String secretKey;
    @Value("${minio.bucketName}") private String bucketName;

    @Bean
    protected MinioClient minioClient() {
        return MinioClient.builder()
            .endpoint(endPoint)
            .credentials(accessKey, secretKey)
            .build();
    }
}

2.4 MinIO utility class

package com.sunny.utils;

import com.sunny.entity.common.ApiResult;
import com.sunny.exception.AppException;
import io.minio.GetPresignedObjectUrlArgs;
import io.minio.MinioClient;
import io.minio.PutObjectArgs;
import io.minio.http.Method;
import jakarta.annotation.Resource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.web.multipart.MultipartFile;
import java.io.InputStream;

@Component
public class MinioUtils {
    @Value("${minio.bucketName}") private String bucketName;
    @Resource private MinioClient minioClient;

    public ApiResult uploadFile(MultipartFile file) throws AppException {
        String fileName = System.currentTimeMillis() + file.getOriginalFilename();
        try (InputStream fi = file.getInputStream()) {
            PutObjectArgs putObjectArgs = PutObjectArgs.builder()
                .bucket(bucketName)
                .contentType(file.getContentType())
                .object(fileName)
                .stream(fi, fi.available(), -1)
                .build();
            minioClient.putObject(putObjectArgs);
        } catch (Exception e) {
            throw new AppException("文件上传失败" + e.getMessage());
        }
        return ApiResult.ok(fileName);
    }

    public ApiResult getPreviewUrl(String objectName) throws AppException {
        try {
            GetPresignedObjectUrlArgs urlArgs = GetPresignedObjectUrlArgs.builder()
                .bucket(bucketName)
                .object(objectName)
                .method(Method.GET)
                .build();
            return ApiResult.ok(minioClient.getPresignedObjectUrl(urlArgs));
        } catch (Exception e) {
            throw new AppException("获取预览链接失败" + e.getMessage());
        }
    }
}

2.5 Controller

package com.sunny.controller;

import com.sunny.entity.common.ApiResult;
import com.sunny.exception.AppException;
import com.sunny.utils.MinioUtils;
import jakarta.annotation.Resource;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

@RestController
@RequestMapping("/file")
public class FileOperationController {
    @Resource private MinioUtils minioUtils;

    @PostMapping("/upload")
    public ApiResult upload(MultipartFile file) throws AppException {
        return minioUtils.uploadFile(file);
    }

    @GetMapping("/getPreviewUrl")
    public ApiResult getPreviewUrl(String fileName) throws AppException {
        return minioUtils.getPreviewUrl(fileName);
    }
}

3. Testing

3.1 Upload file

Send a POST request to /file/upload with a file; the response returns a unique filename stored in MinIO.

3.2 Get preview URL

Call /file/getPreviewUrl with the returned filename to obtain a signed URL for preview.

3.3 File preview

Paste the signed URL into the kkfileviewer interface to view the uploaded document directly in the browser.