overleaf/services/document-updater/app/coffee/RedisBackend.coffee
2016-06-08 16:41:58 +01:00

125 lines
No EOL
3.3 KiB
CoffeeScript

Settings = require "settings-sharelatex"
async = require "async"
_ = require "underscore"
logger = require "logger-sharelatex"
class Client
constructor: (@clients) ->
multi: () ->
return new MultiClient(
@clients.map (client) -> {
rclient: client.rclient.multi()
key_schema: client.key_schema
primary: client.primary
driver: client.driver
}
)
class MultiClient
constructor: (@clients) ->
exec: (callback) ->
jobs = @clients.map (client) ->
(cb) ->
client.rclient.exec (error, result) ->
if client.driver == "ioredis"
# ioredis returns an results like:
# [ [null, 42], [null, "foo"] ]
# where the first entries in each 2-tuple are
# presumably errors for each individual command,
# and the second entry is the result. We need to transform
# this into the same result as the old redis driver:
# [ 42, "foo" ]
filtered_result = []
for entry in result or []
if entry[0]?
return cb(entry[0])
else
filtered_result.push entry[1]
result = filtered_result
if client.primary
# Return this result as the actual result
callback(error, result)
# Send the rest through for comparison
cb(error, result)
async.parallel jobs, (error, results) ->
if error?
logger.error {err: error}, "error in redis backend"
else
compareResults(results)
COMMANDS = {
"get": 0,
"smembers": 0,
"set": 0,
"srem": 0,
"sadd": 0,
"del": 0,
"lrange": 0,
"llen": 0,
"rpush": 0,
"expire": 0,
"ltrim": 0,
"incr": 0,
"eval": 2
}
for command, key_pos of COMMANDS
do (command, key_pos) ->
Client.prototype[command] = (args..., callback) ->
jobs = @clients.map (client) ->
(cb) ->
key_builder = args[key_pos]
key = key_builder(client.key_schema)
args_with_key = args.slice(0)
args_with_key[key_pos] = key
client.rclient[command] args_with_key..., (error, result...) ->
if client.primary
# Return this result as the actual result
callback(error, result...)
# Send the rest through for comparison
cb(error, result...)
async.parallel jobs, (error, results) ->
if error?
logger.error {err: error}, "error in redis backend"
else
compareResults(results)
MultiClient.prototype[command] = (args...) ->
for client in @clients
key_builder = args[key_pos]
key = key_builder(client.key_schema)
args_with_key = args.slice(0)
args_with_key[key_pos] = key
client.rclient[command] args_with_key...
compareResults = (results) ->
return if results.length < 2
first = results[0]
for result in results.slice(1)
if not _.isEqual(first, result)
logger.warn { results }, "redis return values do not match"
module.exports =
createClient: () ->
client_configs = Settings.redis.documentupdater
unless client_configs instanceof Array
client_configs.primary = true
client_configs = [client_configs]
clients = client_configs.map (config) ->
if config.cluster?
Redis = require("ioredis")
rclient = new Redis.Cluster(config.cluster)
driver = "ioredis"
else
{host, port, password} = config
rclient = require("redis-sharelatex").createClient({host, port, password})
driver = "redis"
return {
rclient: rclient
key_schema: config.key_schema
primary: config.primary
driver: driver
}
return new Client(clients)