gitlab-org--gitlab-foss/app/models/broadcast_message.rb
Stan Hu cde78f7f4e Avoid caching BroadcastMessage as an ActiveRecord object
When a Rails 4 host serializes a BroadcastMessage, it will serialize
`ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Integer`, which does
not exist in Rails 5. This will cause Error 500s on a Rails 5 reading
from this cache.

To make Rails 4 and 5 play well together, store the data as JSON and
construct the ActiveRecord objects from JSON.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/55034
2018-12-08 22:06:07 -08:00

108 lines
2.6 KiB
Ruby

# frozen_string_literal: true
class BroadcastMessage < ActiveRecord::Base
include CacheMarkdownField
include Sortable
cache_markdown_field :message, pipeline: :broadcast_message
validates :message, presence: true
validates :starts_at, presence: true
validates :ends_at, presence: true
validates :color, allow_blank: true, color: true
validates :font, allow_blank: true, color: true
default_value_for :color, '#E75E40'
default_value_for :font, '#FFFFFF'
CACHE_KEY = 'broadcast_message_current_json'.freeze
LEGACY_CACHE_KEY = 'broadcast_message_current'.freeze
after_commit :flush_redis_cache
def self.current
raw_messages = Rails.cache.fetch(CACHE_KEY, expires_in: cache_expires_in) do
remove_legacy_cache_key
current_and_future_messages.to_json
end
messages = decode_messages(raw_messages)
return [] unless messages&.present?
now_or_future = messages.select(&:now_or_future?)
# If there are cached entries but none are to be displayed we'll purge the
# cache so we don't keep running this code all the time.
Rails.cache.delete(CACHE_KEY) if now_or_future.empty?
now_or_future.select(&:now?)
end
def self.decode_messages(raw_messages)
return unless raw_messages&.present?
message_list = ActiveSupport::JSON.decode(raw_messages)
return unless message_list.is_a?(Array)
valid_attr = BroadcastMessage.attribute_names
message_list.map do |raw|
BroadcastMessage.new(raw) if valid_cache_entry?(raw, valid_attr)
end.compact
rescue ActiveSupport::JSON.parse_error
end
def self.valid_cache_entry?(raw, valid_attr)
return false unless raw.is_a?(Hash)
(raw.keys - valid_attr).empty?
end
def self.current_and_future_messages
where('ends_at > :now', now: Time.zone.now).order_id_asc
end
def self.cache_expires_in
nil
end
# This can be removed in GitLab 12.0+
# The old cache key had an indefinite lifetime, and in an HA
# environment a one-shot migration would not work because the cache
# would be repopulated by a node that has not been upgraded.
def self.remove_legacy_cache_key
Rails.cache.delete(LEGACY_CACHE_KEY)
end
def active?
started? && !ended?
end
def started?
Time.zone.now >= starts_at
end
def ended?
ends_at < Time.zone.now
end
def now?
(starts_at..ends_at).cover?(Time.zone.now)
end
def future?
starts_at > Time.zone.now
end
def now_or_future?
now? || future?
end
def flush_redis_cache
Rails.cache.delete(CACHE_KEY)
self.class.remove_legacy_cache_key
end
end