`class Assets`

Represents an HTTP middleware for serving static assets.

This middleware serves static files from a configured root directory with appropriate content type headers and caching controls. It supports a wide range of web file formats including HTML, CSS, JavaScript, images, fonts, audio, video, and WebAssembly files.

Definitions

`def initialize(delegate, root: PUBLIC_ROOT, content_types: DEFAULT_CONTENT_TYPES, cache_control: DEFAULT_CACHE_CONTROL)`

Initialize a new assets middleware instance.

Signature

parameter　delegate　Protocol::HTTP::Middleware: The next middleware in the chain.
parameter　root　String: The root directory path for serving assets.
parameter　content_types　Hash: Mapping of file extensions to MIME types.
parameter　cache_control　String: Cache control header value for responses.

Implementation

def initialize(delegate, root: PUBLIC_ROOT, content_types: DEFAULT_CONTENT_TYPES, cache_control: DEFAULT_CACHE_CONTROL)
	super(delegate)
	
	@root = File.expand_path(root)
	
	@content_types = content_types
	@cache_control = cache_control
end

`attr :root`

Signature

attribute　String: The absolute path to the root directory for serving assets.

`attr :content_types`

Signature

attribute　Hash: Mapping of file extensions to content types.

`attr :cache_control`

Signature

attribute　String: Cache control header value for asset responses.

`def freeze`

Freeze this middleware instance and all its configuration.

Signature

returns　Assets: Returns self for method chaining.

Implementation

def freeze
	return self if frozen?
	
	@root.freeze
	@content_types.freeze
	@cache_control.freeze
	
	super
end

`def response_for(path)`

Generate an HTTP response for the given file path.

Signature

parameter　path　String: The absolute file path to serve.
returns　Protocol::HTTP::Response: HTTP response with file content or error.

Implementation

def response_for(path)
	extension = File.extname(path)
	
	if content_type = @content_types[extension]
		headers = [
			["content-type", content_type],
			["cache-control", @cache_control],
		]
		
		return Protocol::HTTP::Response[200, headers, Protocol::HTTP::Body::File.open(path)]
	else
		Console.warn(self, "Unsupported media type!", path: path)
		return Protocol::HTTP::Response[415, [["content-type", "text/plain"]], "Unsupported media type: #{extension.inspect}!"]
	end
end

`def expand_path(path)`

Expand a relative path to an absolute path within the asset root.

Signature

parameter　path　String: The relative path to expand.
returns　String | Nil: The absolute path if valid, nil if the file doesn't exist.

Implementation

def expand_path(path)
	path = path.split("/").map(&URI.method(:decode_uri_component))
	
	root = File.realpath(@root)
	path = File.realpath(File.join(@root, path))
	
	if path.start_with?(root) && File.file?(path)
		return path
	end
rescue Errno::ENOENT
	nil
end

`def call(request)`

Handle an incoming HTTP request.

Signature

parameter　request　Protocol::HTTP::Request: The incoming HTTP request.
returns　Protocol::HTTP::Response: The HTTP response for the asset or delegates to next middleware.

Implementation

def call(request)
	if path = expand_path(request.path)
		return response_for(path)
	end
	
	super
end