ExOss

A unified S3-compatible and Alibaba Cloud OSS object storage library for Elixir with multi-CDN support.

Features

• Native Alibaba Cloud OSS — OSS V4 signing, STS credentials, multipart uploads, and Aliyun CDN
• S3 unified storage — AWS S3, Qiniu S3, MinIO, DigitalOcean Spaces, Cloudflare R2, or any S3-compatible service
• Multi-CDN — CloudFront, Qiniu CDN, Aliyun CDN, and extensible via ExOss.CDN.Behaviour
• Multi-client — configure multiple storage backends and CDNs side by side
• File transfer — upload from file, content, remote URL, or cloud-to-cloud copy
• Presigned URLs — temporary direct-access upload/download without exposing credentials

Installation

Add ex_oss to your dependencies:

def deps do
  [
    {:ex_oss, "~> 1.2"}
  ]
end

Quick Start

# 1. Define a storage module
defmodule MyApp.Storage do
  use ExOss, otp_app: :my_app
end

# 2. Add configuration
config :my_app, MyApp.Storage,
  provider: :aws,
  access_key_id: "your-access-key",
  secret_access_key: "your-secret-key",
  region: "us-east-1"

# 3. Use it
MyApp.Storage.upload_credential("bucket", "path/file.jpg", 3600)
MyApp.Storage.authorize_download_url("bucket", "path/file.jpg", 3600)

See the getting started guide for details.

Alibaba Cloud and upload headers

See the Aliyun OSS guide and Aliyun CDN guide for native configuration.

Both server uploads and presigned PUT credentials accept raw opts[:headers]. Both opts[:content_type] and opts["content_type"] populate the "content-type" header for all storage providers; an explicit Content-Type header wins. Send the returned headers unchanged when uploading with a credential:

credential = MyApp.Storage.upload_credential("bucket", "photo.png", 3600,
  headers: %{"content-type" => "image/png", "cache-control" => "max-age=3600"}
)
Req.put!(credential.presigned_url, body: file_content, headers: credential.headers)

Existing calls without options still work. Provider-specific headers are passed through without translation; consult the provider's API for supported values.

License

MIT