Minio WebUI

Using S3 libraries with Minio mock server


In the continuation of my previous S3 article,

I present you, how to write a S3 Java Sample program that is using a mock S3 server to develop the functionalities.

In this article, I will be using :

First step : running our mock S3 server

We will use Minio as our fake S3 server.

You need to have Docker installed on your machine. Once Docker installed. type the following commands in your terminal :

docker pull /minio
docker run -p 9000:9000 minio/minio server /data


Your terminal should show you something similar to this screenshot :

Minio launching using Docker
Minio launching using Docker

The following informations are important :

  • Your access key
  • Your secret token
  • And the endpoint

With your browser, you can open an UI on Minio and browse your buckets and objects :


I modified my Java example to pass all the informations (link) :

public  AmazonS3Example {

    private static final Logger LOGGER = LoggerFactory.getLogger(AmazonS3Example.class);

    public static void main(final String[] args) {

	final AmazonArgs amazonArgs = new AmazonArgs();


My is doing these basic tasks :

  • Creating a bucket
  • Get the list of buckets on the server
  • Checking for the existence of this newly created bucket
  • Creating a folder inside this bucket
  • Uploading a file in the folder of this bucket (creates a new object)
  • Reading the object content
  • Deleting the folder
  • Deleting the bucket

Feedback : When writing my example, I had some issues with the Amazon s3 client (especially the v2 methods to detect the presence of an object, a cluster) and with the RegionName of the Amazon client that is guessing the region based on the source endpoint. You should rather store this information as a configuration , accessible by all your objects.

Next to read  Code generation and data generator : the best use cases

Using Minio and a S3 code seems to be easy, for most of the S3 basic operations.

Have you tried it ? What is your opinion about Minio ?


Sylvain Leroy

Senior Software Quality Manager and Solution Architect in Switzerland, I have previously created my own company, Tocea, in Software Quality Assurance. Now I am offering my knowledge and services in a small IT Consulting company : Byoskill and a website www.byoskill.com Currently living in Lausanne (CH)

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