CloudfrontSigner

Elixir implementation of Cloudfront's url signature algorithm. Supports expiration policies and runtime configurable distributions.

Installation

If available in Hex, the package can be installed by adding cloudfront_signer to your list of dependencies in mix.exs:

def deps do
  [
    {:cloudfront_signer, "~> 0.3.0"}
  ]
end

Configure a distribution with:

config :my_app, :my_distribution,
  domain: "https://some.cloudfront.domain",
  private_key: {:system, "ENV_VAR"}, # or {:file, "/path/to/key"}
  key_pair_id: {:system, "OTHER_ENV_VAR"}

Then simply do:

CloudfrontSigner.Distribution.from_config(:my_app, :my_distribution)
|> CloudfrontSigner.sign(path, [arg: "value"], expiry_in_seconds)

If you want to cache pem decodes (which is a wise choice), a registry of decoded distributions is available. Simply do:

CloudfrontSigner.DistributionRegistry.get_distribution(:my_app, :my_distribution)
|> CloudfrontSigner.sign(path, [arg: "value], expiry)

By default it uses Poison, but you can specify a different JSON processor such as Jason by setting this in your config.exs:

config :cloudfront_signer, :json_codec, Jason