If you deal with some kind of database, you should know by now that Redis is TEH AWESOME.

As part of the provided tools, the redis-cli binary is an invaluable tool to connect to a Redis database, via a TCP port or a UNIX socket (my preferred way).

Once connected to a Redis server via redis-cli you can send the MONITOR command. The clients then stops listening to regular inputs and starts to log every command received by the server, with a timestamp (seconds and microseconds).

Here is an output sample :

1353711173.069255 "MONITOR"
1353711204.631496 "SET" "users:1:login" "alfred"
1353711224.119123 "SET" "users:2:login" "tom"
1353711281.926336 "SADD" "users" "1" "2"
1353711297.878012 "SMEMBERS" "users"

The problem is that there doesn’t seem to be a built-in way to filter or save the command logs.

Redis being a good UNIX citizen acts like any other command regarding to input, outputs and pipes.

Let’s assume that the server is reachable on the default TCP port,

• To simply print a command log
  echo "MONITOR" | redis-cli
• To print a filtered command log (only “add to Sets”)
  echo "MONITOR" | redis-cli | grep -i 'SADD'
• To save a command log to a file
  echo "MONITOR" | redis-cli > redis.log
• To save a filtered command log to a file
  echo "MONITOR" | redis-cli | grep -i 'SADD' > redis.log

NB : Redis is case insensitive for the commands it accepts.