Ensure 3rd-party s3 compatible storage works

[c-nv-s]

Is your feature request related to a problem? Please describe.
This will need some investigating, but static backend should allow developers to use their own preferred s3-compatible storage and not just be limited to AWS.

example s3 compatible alternatives:
https://github.com/minio/minio
https://www.backblaze.com/b2/docs/s3_compatible_api.html
https://wasabi.com/s3-compatible-cloud-storage/
https://www.scaleway.com/en/object-storage/

[dstpierre]

I wonder if the current AWS SDK can also be used directly for compatible alternative.

At this moment, there's still an hard-coded value in the s3 implementation that should not be hard-coded:

core/storage/s3.go

Line 17 in 18e8620

sess, err := session.NewSession(&aws.Config{Region: aws.String("ca-central-1")})

If it's possible to use these "compatible" providers with the AWS SDK / current code in the s3 implementation once this hard-coded value is in the config package, I guess it's just a matter of configuring the AWS environment variables that matches with the provider:

AWS_ACCESS_KEY_ID=your-aws-key
AWS_SECRET_ACCESS_KEY=your-aws-secret
AWS_SECRET_KEY=your-aws-key
AWS_SES_ENDPOINT=https://email.us-east-1.amazonaws.com
AWS_REGION=us-east-1
AWS_S3_BUCKET=your.bucketname.here
AWS_CDN_URL=https://your.cdnurlhere.com

If someone is interested in testing this. I believe updating the code in the storage/s3.go implementation to use the AWS_REGION instead of the hard-coded one and configuring those value to match a provider and tests would be how I'd do that one.