debian-mirror-gitlab/lib/mattermost/session.rb
2020-11-24 15:15:51 +05:30

188 lines
4.6 KiB
Ruby

# frozen_string_literal: true
module Mattermost
class NoSessionError < Mattermost::Error
def message
'No session could be set up, is Mattermost configured with Single Sign On?'
end
end
ConnectionError = Class.new(Mattermost::Error)
# This class' prime objective is to obtain a session token on a Mattermost
# instance with SSO configured where this GitLab instance is the provider.
#
# The process depends on OAuth, but skips a step in the authentication cycle.
# For example, usually a user would click the 'login in GitLab' button on
# Mattermost, which would yield a 302 status code and redirects you to GitLab
# to approve the use of your account on Mattermost. Which would trigger a
# callback so Mattermost knows this request is approved and gets the required
# data to create the user account etc.
#
# This class however skips the button click, and also the approval phase to
# speed up the process and keep it without manual action and get a session
# going.
class Session
include Doorkeeper::Helpers::Controller
LEASE_TIMEOUT = 60
attr_accessor :current_resource_owner, :token, :base_uri
def initialize(current_user)
@current_resource_owner = current_user
@base_uri = Settings.mattermost.host
end
def with_session
with_lease do
create
begin
yield self
rescue Errno::ECONNREFUSED => e
Gitlab::AppLogger.error(e.message + "\n" + e.backtrace.join("\n"))
raise Mattermost::NoSessionError
ensure
destroy
end
end
end
# Next methods are needed for Doorkeeper
def pre_auth
@pre_auth ||= Doorkeeper::OAuth::PreAuthorization.new(
Doorkeeper.configuration, params)
end
def authorization
@authorization ||= strategy.request
end
def strategy
@strategy ||= server.authorization_request(pre_auth.response_type)
end
def request
@request ||= OpenStruct.new(parameters: params)
end
def params
Rack::Utils.parse_query(oauth_uri.query).symbolize_keys
end
def get(path, options = {})
handle_exceptions do
Gitlab::HTTP.get(path, build_options(options))
end
end
def post(path, options = {})
handle_exceptions do
Gitlab::HTTP.post(path, build_options(options))
end
end
def delete(path, options = {})
handle_exceptions do
Gitlab::HTTP.delete(path, build_options(options))
end
end
private
def build_options(options)
options.tap do |hash|
hash[:headers] = @headers
hash[:allow_local_requests] = true
hash[:base_uri] = base_uri if base_uri.presence
end
end
def create
raise Mattermost::NoSessionError unless oauth_uri
raise Mattermost::NoSessionError unless token_uri
@token = request_token
raise Mattermost::NoSessionError unless @token
@headers = {
Authorization: "Bearer #{@token}"
}
@token
end
def destroy
post('/api/v4/users/logout')
end
def oauth_uri
return @oauth_uri if defined?(@oauth_uri)
@oauth_uri = nil
response = get('/oauth/gitlab/login', follow_redirects: false)
return unless (300...400) === response.code
redirect_uri = response.headers['location']
return unless redirect_uri
oauth_cookie = parse_cookie(response)
@headers = {
Cookie: oauth_cookie.to_cookie_string
}
@oauth_uri = URI.parse(redirect_uri)
end
def token_uri
@token_uri ||=
if oauth_uri
authorization.authorize.redirect_uri if pre_auth.authorizable?
end
end
def request_token
response = get(token_uri, follow_redirects: false)
if (200...400) === response.code
response.headers['token']
end
end
def with_lease
lease_uuid = lease_try_obtain
raise NoSessionError unless lease_uuid
begin
yield
ensure
Gitlab::ExclusiveLease.cancel(lease_key, lease_uuid)
end
end
def lease_key
"mattermost:session"
end
def lease_try_obtain
lease = ::Gitlab::ExclusiveLease.new(lease_key, timeout: LEASE_TIMEOUT)
lease.try_obtain
end
def handle_exceptions
yield
rescue Gitlab::HTTP::Error => e
raise Mattermost::ConnectionError.new(e.message)
rescue Errno::ECONNREFUSED => e
raise Mattermost::ConnectionError.new(e.message)
end
def parse_cookie(response)
cookie_hash = Gitlab::HTTP::CookieHash.new
response.get_fields('Set-Cookie').each { |c| cookie_hash.add_cookies(c) }
cookie_hash
end
end
end