discourse/lib/cache.rb
Sam Saffron 30990006a9 DEV: enable frozen string literal on all files
This reduces chances of errors where consumers of strings mutate inputs
and reduces memory usage of the app.

Test suite passes now, but there may be some stuff left, so we will run
a few sites on a branch prior to merging
2019-05-13 09:31:32 +08:00

63 lines
1.2 KiB
Ruby

# frozen_string_literal: true
# Discourse specific cache, enforces 1 day expiry
class Cache < ActiveSupport::Cache::Store
# nothing is cached for longer than 1 day EVER
# there is no reason to have data older than this clogging redis
# it is dangerous cause if we rename keys we will be stuck with
# pointless data
MAX_CACHE_AGE = 1.day unless defined? MAX_CACHE_AGE
def initialize(opts = {})
@namespace = opts[:namespace] || "_CACHE_"
super(opts)
end
def redis
$redis
end
def reconnect
redis.reconnect
end
def keys(pattern = "*")
redis.scan_each(match: "#{@namespace}:#{pattern}").to_a
end
def clear
keys.each do |k|
redis.del(k)
end
end
def normalize_key(key, opts = nil)
"#{@namespace}:#{key}"
end
protected
def read_entry(key, options)
if data = redis.get(key)
data = Marshal.load(data)
ActiveSupport::Cache::Entry.new data
end
rescue
# corrupt cache, fail silently for now, remove rescue later
end
def write_entry(key, entry, options)
dumped = Marshal.dump(entry.value)
expiry = options[:expires_in] || MAX_CACHE_AGE
redis.setex(key, expiry, dumped)
true
end
def delete_entry(key, options)
redis.del key
end
end