Use AWS sdk ruby with custom AWS endpoints.json

I am deploying some services on a different cloud than the AWS cloud, but that exposes AWS compatible endpoints.

I was given an endpoints.json file that looks like this

{
  "partitions": [
    {
      "defaults": {
        "hostname": "{service}.{region}.{dnsSuffix}",
        "protocols": [
          "https"
        ],
        "signatureVersions": [
          "v4"
        ]
      },
      "dnsSuffix": "outscale.com",
      "partition": "osc",
      "partitionName": "Outscale",
      "regionRegex": "^(cloudgouv|us|eu|ap)\\-\\w+\\-\\d+$",
      "regions": {
        "eu-west-2": {
          "description": "EU (Paris)"
        },
        [...]
      },
      "services": {
        "ec2": {
          "endpoints": {
            "eu-west-2": {"hostname": "fcu.eu-west-2.outscale.com"},
            [...]
          }
        },

How can I easily import this in my AWS sdk v3 ? When looking at the doc there seems to be something quite similar available, but I'm not sure I understand how to load this config from my ruby code

I know I can do something like this

Aws.config.update(
  region: 'cloudgouv-eu-west-1'
)

But I'm not sure how to import the whole config (and especially the endpoints name, etc.) so they will automatically be used by underlying sdks without changing too much code

I ended up using AWS internal API to add partitions

# config/initializers/aws.rb
# Monkeypatch the list of AWS endpoints
new_partitions = JSON.parse(
  File.read(
    Rails.root.join('config', 'aws_endpoints_outscale.json')
  )
)
Aws::Partitions.add(new_partitions)

Aws.config.update(
  region: ENV['AWS_REGION'],
  endpoint: 'outscale.com',
)