discourse/lib/discourse_redis.rb

287 lines
5.2 KiB
Ruby

# frozen_string_literal: true
#
# A wrapper around redis that namespaces keys with the current site id
#
class DiscourseRedis
def self.raw_connection(config = nil)
config ||= self.config
Redis.new(config)
end
def self.config
GlobalSetting.redis_config
end
def initialize(config = nil, namespace: true, raw_redis: nil)
@config = config || DiscourseRedis.config
@redis = raw_redis || DiscourseRedis.raw_connection(@config.dup)
@namespace = namespace
end
def without_namespace
# Only use this if you want to store and fetch data that's shared between sites
@redis
end
def self.ignore_readonly
yield
rescue Redis::CommandError => ex
if ex.message =~ /READONLY/
Discourse.received_redis_readonly!
nil
else
raise ex
end
end
# prefix the key with the namespace
def method_missing(meth, *args, **kwargs, &block)
if @redis.respond_to?(meth)
DiscourseRedis.ignore_readonly { @redis.public_send(meth, *args, **kwargs, &block) }
else
super
end
end
# Proxy key methods through, but prefix the keys with the namespace
%i[
append
blpop
brpop
brpoplpush
decr
decrby
expire
expireat
get
getbit
getrange
getset
hdel
hexists
hget
hgetall
hincrby
hincrbyfloat
hkeys
hlen
hmget
hmset
hset
hsetnx
hvals
incr
incrby
incrbyfloat
lindex
linsert
llen
lpop
lpush
lpushx
lrange
lrem
lset
ltrim
mapped_hmset
mapped_hmget
mapped_mget
mapped_mset
mapped_msetnx
move
mset
msetnx
persist
pexpire
pexpireat
psetex
pttl
rename
renamenx
rpop
rpoplpush
rpush
rpushx
sadd
sadd?
scard
sdiff
set
setbit
setex
setnx
setrange
sinter
sismember
smembers
sort
spop
srandmember
srem
srem?
strlen
sunion
ttl
type
watch
zadd
zcard
zcount
zincrby
zrange
zrangebyscore
zrank
zrem
zremrangebyrank
zremrangebyscore
zrevrange
zrevrangebyscore
zrevrank
zrangebyscore
dump
restore
].each do |m|
define_method m do |*args, **kwargs|
args[0] = "#{namespace}:#{args[0]}" if @namespace
DiscourseRedis.ignore_readonly { @redis.public_send(m, *args, **kwargs) }
end
end
def exists(*args)
args.map! { |a| "#{namespace}:#{a}" } if @namespace
DiscourseRedis.ignore_readonly { @redis.exists(*args) }
end
def exists?(*args)
args.map! { |a| "#{namespace}:#{a}" } if @namespace
DiscourseRedis.ignore_readonly { @redis.exists?(*args) }
end
def mget(*args)
args.map! { |a| "#{namespace}:#{a}" } if @namespace
DiscourseRedis.ignore_readonly { @redis.mget(*args) }
end
def del(*keys)
DiscourseRedis.ignore_readonly do
keys = keys.flatten(1)
keys.map! { |k| "#{namespace}:#{k}" } if @namespace
@redis.del(*keys)
end
end
def scan_each(options = {}, &block)
DiscourseRedis.ignore_readonly do
match = options[:match].presence || "*"
options[:match] = if @namespace
"#{namespace}:#{match}"
else
match
end
if block
@redis.scan_each(**options) do |key|
key = remove_namespace(key) if @namespace
block.call(key)
end
else
@redis
.scan_each(**options)
.map do |key|
key = remove_namespace(key) if @namespace
key
end
end
end
end
def keys(pattern = nil)
DiscourseRedis.ignore_readonly do
pattern = pattern || "*"
pattern = "#{namespace}:#{pattern}" if @namespace
keys = @redis.keys(pattern)
if @namespace
len = namespace.length + 1
keys.map! { |k| k[len..-1] }
end
keys
end
end
def delete_prefixed(prefix)
DiscourseRedis.ignore_readonly { keys("#{prefix}*").each { |k| Discourse.redis.del(k) } }
end
def reconnect
@redis._client.reconnect
end
def namespace_key(key)
if @namespace
"#{namespace}:#{key}"
else
key
end
end
def namespace
RailsMultisite::ConnectionManagement.current_db
end
def self.new_redis_store
Cache.new
end
def multi
DiscourseRedis.ignore_readonly do
if block_given?
@redis.multi do |transaction|
yield DiscourseRedis.new(@config, namespace: @namespace, raw_redis: transaction)
end
else
@redis.multi
end
end
end
def pipelined
DiscourseRedis.ignore_readonly do
if block_given?
@redis.pipelined do |transaction|
yield DiscourseRedis.new(@config, namespace: @namespace, raw_redis: transaction)
end
else
@redis.pipelined
end
end
end
private
def remove_namespace(key)
key[(namespace.length + 1)..-1]
end
class EvalHelper
def initialize(script)
@script = script
@sha1 = Digest::SHA1.hexdigest(script)
end
def eval(redis, *args, **kwargs)
redis.evalsha @sha1, *args, **kwargs
rescue ::Redis::CommandError => e
if e.to_s =~ /^NOSCRIPT/
redis.eval @script, *args, **kwargs
else
raise
end
end
end
end