module Middleware

module Versioner

# This middleware sets various version related rack environment variables

# based on the uri path and removes the version substring from the uri

# path. If the version substring does not match any potential initialized

# versions, a 404 error is thrown.

#

# Example: For a uri path

# /v1/resource

#

# The following rack env variables are set and path is rewritten to

# '/resource':

#

# env['api.version'] => 'v1'

#

class Path < Base

def default_options

{

pattern: /.*/i

}

end

def before

path = env['PATH_INFO'].dup

if prefix && path.index(prefix) == 0

path.sub!(prefix, '')

path = Rack::Mount::Utils.normalize_path(path)

end

pieces = path.split('/')

potential_version = pieces[1]

if potential_version =~ options[:pattern]

if options[:versions] && !options[:versions].find { |v| v.to_s == potential_version }

throw :error, status: 404, message: "404 API Version Not Found"

end

env['api.version'] = potential_version

end

end

private

def prefix

Rack::Mount::Utils.normalize_path(options[:prefix].to_s) if options[:prefix]

end

end

end

end