Godis

中文版

Godis is a simple implementation of Redis Server, which intents to provide an example of writing a high concurrent middleware using golang.

Please be advised, NEVER think about using this in production environment.

This repository implemented most features of redis, including 5 data structures, ttl, publish/subscribe, AOF persistence and server side cluster mode.

If you could read Chinese, you can find more details in My Blog.

Running

You can get runnable program in the releases of this repository, which supports Linux and Darwin system.

./godis-darwin

You could use redis-cli or other redis client to connect godis server, which listens on 127.0.0.1:6379 on default mode.

The program will try to read config file path from environment variable CONFIG.

If environment variable is not set, then the program try to read redis.conf in the working directory.

If there is no such file, then the program will run with default config.

cluster mode

Godis can work in cluster mode, please append following lines to redis.conf file

peers localhost:7379,localhost:7389 // other node in cluster
self  localhost:6399 // self address

We provide node1.conf and node2.conf for demonstration. use following command line to start a two-node-cluster:

CONFIG=node1.conf ./godis-darwin &
CONFIG=node2.conf ./godis-darwin &

The cluster is transparent to client. You can connect to any node in the cluster to access all data in the cluster:

redis-cli -p 6399

Commands

Supported Commands:

• Keys
  • del
  • expire
  • expireat
  • pexpire
  • pexpireat
  • ttl
  • pttl
  • persist
  • exists
  • type
  • rename
  • renamenx
• Server
  • flushdb
  • flushall
  • keys
  • bgrewriteaof
• String
  • set
  • setnx
  • setex
  • psetex
  • mset
  • mget
  • msetnx
  • get
  • getset
  • incr
  • incrby
  • incrbyfloat
  • decr
  • decrby
• List
  • lpush
  • lpushx
  • rpush
  • rpushx
  • lpop
  • rpop
  • rpoplpush
  • lrem
  • llen
  • lindex
  • lset
  • lrange
• Hash
  • hset
  • hsetnx
  • hget
  • hexists
  • hdel
  • hlen
  • hmget
  • hmset
  • hkeys
  • hvals
  • hgetall
  • hincrby
  • hincrbyfloat
• Set
  • sadd
  • sismember
  • srem
  • scard
  • smembers
  • sinter
  • sinterstore
  • sunion
  • sunionstore
  • sdiff
  • sdiffstore
  • srandmember
• SortedSet
  • zadd
  • zscore
  • zincrby
  • zrank
  • zcount
  • zrevrank
  • zcard
  • zrange
  • zrevrange
  • zrangebyscore
  • zrevrangebyscore
  • zrem
  • zremrangebyscore
  • zremrangebyrank
• Pub / Sub
  • publish
  • subscribe
  • unsubscribe

Read My Code

If you want to read my code in this repository, here is a simple guidance.

• cmd: only the entry point
• config: config parser
• interface: some interface definitions
• lib: some utils, such as logger, sync utils and wildcard

I suggest focusing on the following directories:

• tcp: the tcp server
• redis: the redis protocol parser
• datastruct: the implements of data structures
  • dict: a concurrent hash map
  • list: a linked list
  • lock: it is used to lock keys to ensure thread safety
  • set: a hash set based on map
  • sortedset: a sorted set implements based on skiplist
• db: the implements of the redis db
  • db.go: the basement of database
  • router.go: it find handler for commands
  • keys.go: handlers for keys commands
  • string.go: handlers for string commands
  • list.go: handlers for list commands
  • hash.go: handlers for hash commands
  • set.go: handlers for set commands
  • sortedset.go: handlers for sorted set commands
  • pubsub.go: implements of publish / subscribe
  • aof.go: implements of AOF persistence and rewrite

License

This project is licensed under the GPL license.