canvas-lms/app/models/notification_endpoint.rb

98 lines
2.8 KiB
Ruby

#
# Copyright (C) 2015 Instructure, Inc.
#
# This file is part of Canvas.
#
# Canvas is free software: you can redistribute it and/or modify it under
# the terms of the GNU Affero General Public License as published by the Free
# Software Foundation, version 3 of the License.
#
# Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
# details.
#
# You should have received a copy of the GNU Affero General Public License along
# with this program. If not, see <http://www.gnu.org/licenses/>.
#
require 'aws-sdk'
class NotificationEndpoint < ActiveRecord::Base
attr_accessible :token, :arn
belongs_to :access_token
validates_presence_of :token, :access_token
before_create :create_platform_endpoint
after_destroy :delete_platform_endpoint
def push_json(json)
return false unless endpoint_exists? && own_endpoint? && endpoint_enabled? && !token_changed?
sns_client.publish(target_arn: self.arn, message: json, message_structure: 'json')
end
private
DIFFERENT_ATTRIBUTES_ERROR_REGEX = %r{^Invalid parameter: Token Reason: Endpoint (.*) already exists with the same Token, but different attributes.$}
def sns_client
DeveloperKey.sns.client
end
def endpoint_attributes
@endpoint_attributes ||= begin
response = sns_client.get_endpoint_attributes(endpoint_arn: self.arn)
response[:attributes]
end
end
def endpoint_exists?
begin
endpoint_attributes
true
rescue AWS::SNS::Errors::NotFound
false
end
end
def own_endpoint?
endpoint_attributes['CustomUserData'] == access_token.global_id.to_s
end
def endpoint_enabled?
endpoint_attributes['Enabled'] == 'true'
end
def token_changed?
self.token != endpoint_attributes['Token']
end
def create_platform_endpoint
# try to create new or find existing with our access_token
begin
response = sns_client.create_platform_endpoint(
platform_application_arn: access_token.developer_key.sns_arn,
token: self.token,
custom_user_data: access_token.global_id.to_s
)
self.arn = response[:endpoint_arn]
rescue AWS::SNS::Errors::InvalidParameter => e
# parse already existing with different access_token from the response message
raise unless DIFFERENT_ATTRIBUTES_ERROR_REGEX.match(e.message)
self.arn = $1
# steal the endpoint by setting the access token
sns_client.set_endpoint_attributes(
endpoint_arn: self.arn,
attributes: {'CustomUserData' => access_token.global_id.to_s}
)
end
end
def delete_platform_endpoint
return unless endpoint_exists? && own_endpoint?
sns_client.delete_endpoint(endpoint_arn: self.arn)
end
end