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 before

path_info = Grape::Router.normalize_path(env[Rack::PATH_INFO])

return if path_info == '/'

[mount_path, Grape::Router.normalize_path(prefix)].each do |path|

path_info.delete_prefix!(path) if path.present? && path != '/' && path_info.start_with?(path)

end

slash_position = path_info.index('/', 1) # omit the first one

return unless slash_position

potential_version = path_info[1..slash_position - 1]

return unless potential_version.match?(pattern)

version_not_found! unless potential_version_match?(potential_version)

env[Grape::Env::API_VERSION] = potential_version

end

end

end

end