Springboot Communication with S3 bucket - amazon-web-services

Question

i have got a problem i can't resolve for some hours, so i decide to post it with the hope someone can help me there.
So basically i'm trying to connect my springboot to an s3 bucket i created on the AWS console manager and store some images i supply.
Here is my code java :
#Service
public class AmazonClient {
private AmazonS3 s3client;
#Value("${amazonProperties.endpointUrl}")
private String endpointUrl;
#Value("${amazonProperties.bucketName}")
private String bucketName;
#Value("${amazonProperties.accessKey}")
private String accessKey;
#Value("${amazonProperties.secretKey}")
private String secretKey;
#Value("${amazonProperties.region}")
private String region;
#PostConstruct
private void initializeAmazon() {
System.out.println(this.accessKey+'\n'+this.secretKey+'\n'+Regions.fromName(this.region));
BasicAWSCredentials credentials = new BasicAWSCredentials(this.accessKey, this.secretKey);
AmazonS3 amazonS3Client = AmazonS3ClientBuilder.standard()
.withRegion(Regions.fromName(region))
.withCredentials(new AWSStaticCredentialsProvider(credentials))
.build();
this.s3client = amazonS3Client;
System.out.println(this.s3client);
}
private void uploadFileTos3bucket(String fileName, File file) {
s3client.putObject(new PutObjectRequest(bucketName, fileName, file)
.withCannedAcl(CannedAccessControlList.PublicRead));
}
public String uploadFile(MultipartFile multipartFile) {
String fileUrl = "";
try {
File file = convertMultiPartToFile(multipartFile);
String fileName = generateFileName(multipartFile);
fileUrl = endpointUrl + "/" + bucketName + "/" + fileName;
uploadFileTos3bucket(fileName, file);
file.delete();
} catch (Exception e) {
e.printStackTrace();
}
return fileUrl;
}
}
Getting com.amazonaws.services.s3.model.AmazonS3Exception: The AWS Access Key Id you provided does not exist in our records. (Service: Amazon S3; Status Code: 403; Error Code: InvalidAccessKeyId; Request ID: TDH3Q44GGPGGY2DD; S3 Extended Request ID: oQOOA9bu3bhoHNudJEOFkto1aXEjxKVfblnFWAJ2eJmFTG6mnKSHycHeQpbLP4kYITG9pQxNx9o=; Proxy: null), S3 Extended Request ID: oQOOA9bu3bhoHNudJEOFkto1aXEjxKVfblnFWAJ2eJmFTG6mnKSHycHeQpbLP4kYITG9pQxNx9o=
error when i call the upload method throught postman post request intercepted by controler...
The thing is i can't create an IAM user because i got a restricted AWS free 100$ account given by my school to work on. The permissions S3fullaccess is given to a predifined role assigned to current user. Consequently, aws CLI command aws s3 ls well list the bucket with accurate credential configuration. However, cant put any object in the bucket ....
I'm driving crazy because it seems like everything is working on the springboot part : the println(accesskey, secretkey and region are well fetched from my application.yml following:
amazonProperties:
endpointUrl: https://s3.amazonaws.com
accessKey: XXXXXX
secretKey: XXXXXX
bucketName: image-bucket-cpe
region: us-east-1
).
If someone can help me, i will be forever beholden to him.
Thanks in advance