Redis is a key-value store that can also be used as a publish-subscribe server. It features high speed, data persistence, transactions, replication, and supports common data types like strings, hashes, lists, sets, sorted sets. It has many client libraries and can be used for caching, sessions, storing unrelated data, collecting statistics, communication between processes, and building simple graphs.

1. маленький помощник
больших приложений
Андрей Савченко
Aejis

2. Что такое Redis?
Key-value хранилище
Publish-subscribe сервер

3. Особенности
Высокая скорость
Персистентность данных
Транзакции, репликация

4. Типы данных
Строка (String)
Хеш (Hash)
Список (List)
Множество (Set)
Упорядоченное множество (Sorted set)

5. Клиенты
ActionScript, C, C#, C++, Clojure,
Common Lisp, Erlang, Go, Haskell,
haXe, Io, Java, Lua, Node.js,
Objective-C, Perl, PHP, Python,
Ruby, Scala, Smalltalk, Tcl

6. Cтроки
SET testkey “Hello”
GET testkey
MSET key1 “Hello” key2 “world”
SET counter 1
INCR counter
GET counter #=> “2”

7. Xеши
HSET test key1 “Hello”
HSET test key2 “World”
HGET test key2 #=> “World”
HGETALL test #=> “key1” “Hello” “key2” “World”

8. Списки
RPUSH test “zero”
RPUSH test “one”
RPUSH test “two”
LRANGE test 1 2 #=> “one” “two”

9. Множества
SADD users “andrey”
SADD users “dima”
SCARD users #=> 2
SISMEMBER users “andrey” #=> 1
SISMEMBER users “gleb” #=> 0

10. Практическое
применение

11. Кеши, сессии
Инвалидация по времени
SET a18f045 “cache content”
EXPIRE a18f045 100

12. Кеши, сессии
Инвалидация по признаку
SET a18b045 “cache content”
SET d98f0c9 “cache content”
SADD cond1 a18b045
SADD cond1 d98f0c9
SMEMBERS cond1
DEL {result of smembers}

13. Хранение несвязанных
(малосвязанных)
данных
{user_id = 1}
HSET settings:1 receive_emails “1”
HSET settings:1 records_per_page “20”
HSET settings:1 preffered_syntax “markdown”
HGETALL settings:1

14. Сбор статистики
{post_id=42}
INCR posts:42
GET posts:42 # How many views/votes?
ZINCRBY posts 1 42
ZSCORE posts 42 # How many views/votes?
ZREVRANGE posts O 9 # TOP-10 posts
ZREVRANGE posts O 9 WITHSCORES # TOP-10 with
views/votes quantity

15. Связь между демонами
Websocket
server
Web-application
Async jobs
server

16. Связь между демонами
# Websocket server:
SUBSCRIBE messages
# Async jobs server:
SUBSCRIBE jobs
# Web-application:
PUBLISH jobs “videos:12:mpeg:ogg”
PUBLISH messages “Video encoding #12 started”
# Async jobs server:
PUBLISH messages “Video encoding #12 finished”

17. Построение простых
графов
# User 1 adds user 5 to friends
SADD users:1:friends 5
SADD users:5:friend_of 1
...
# Get user 5 friends
SMEMBERS users:5:friends
# Get user 5 mutual friends
SCARD users:5:friends users:5:friend_of
# Get common friens of user 5 and 7
SCARD users:5:friends users:7:friends
# Are user 7 friend of user 5?
SISMEMBER users:5:friends 7

18. Вопросы?
redis.io/commands
andrey@aejis.eu
twitter.com/ptico