S3-based storage implementation for AWS S3 and S3-compatible services.

Supports three provider modes:

• :aws — Standard AWS S3 (endpoint auto-constructed as s3.{region}.amazonaws.com)
• :qiniu — Qiniu S3-compatible API (endpoint auto-constructed as s3.{region}.qiniucs.com)
• :custom — Any S3-compatible service (MinIO, DigitalOcean Spaces, Cloudflare R2, etc.) Requires an explicit endpoint to be configured.

All storage operations go through ex_aws_s3.

File Transfer Operations

Use run/2 with an ExOss.StorageTask struct to perform uploads, copies, deletes, and content uploads:

# Upload from local file
ExOss.Storage.run(client, %ExOss.StorageTask{
  source: {:file, "/path/to/file.jpg"},
  target: {:cloud, "bucket", "uploads/file.jpg"}
})

# Upload from remote URL
ExOss.Storage.run(client, %ExOss.StorageTask{
  source: {:remote, "https://example.com/file.jpg"},
  target: {:cloud, "bucket", "uploads/file.jpg"}
})

# Cloud-to-cloud copy
ExOss.Storage.run(client, %ExOss.StorageTask{
  source: {:cloud, "source-bucket", "file.jpg"},
  target: {:cloud, "target-bucket", "copies/file.jpg"}
})

# Delete immediately
ExOss.Storage.run(client, %ExOss.StorageTask{
  source: {:cloud, "bucket", "file.jpg"},
  target: nil
})

# Delete after N days (via lifecycle tags)
ExOss.Storage.run(client, %ExOss.StorageTask{
  source: {:cloud, "bucket", "file.jpg"},
  target: nil,
  opts: [days: 30]
})

Presigned URLs

Generate temporary, direct-access URLs without CDN:

# Download URL (presigned GET)
ExOss.Storage.authorize_download_url(client, "bucket", "file.jpg", 3600)

# Upload URL (presigned PUT)
ExOss.Storage.upload_credential(client, "bucket", "file.jpg", 3600)

When a CDN is configured on the client, use ExOss.Runner instead — it automatically routes to the CDN adapter when cdn_download / cdn_upload are enabled.