Hedis

Hedis stands for "Hyper Redis". It can retrieve data from ANY database directly and stores to itself.

What is Hedis?

Traditionally, application server retrieves hot data from in-memory database (like Redis) to reduce unnecessary paths. If in-memory database doesn't have specific data, application server gets back to retrieve data from original database.

Hedis can retrieve data from ANY database directly. Application server retrieves hot data from Hedis server, If Hedis server doesn't have specific data, Hedis retrieves data from original database via ANY connector.

Hedis configuration file

cdh1: # connector name (required)
  type: hbase # connector type (required)
  zookeeper: localhost:2181 # other configuration (depends on its type)
mysqltest:
  type: mysql
  username: root
  password: MY_PASSWORD
  host: localhost
  database: hedistest
otherdb:
  type: gooddb

Connectors

• hedis-connector-template
• hedis-connector-hbase
• hedis-connector-mysql

How to run

First all

Sets environment variables on various connectors

# HBase environment variables

export CLASSPATH=/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/async-1.4.0.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/asynchbase-1.5.0-libhbase-20140311.193218-1.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/commons-configuration-1.6.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/commons-lang-2.5.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/commons-logging-1.1.1.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/hadoop-core-1.0.4.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/hbase-0.94.17.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/libhbase-1.0-SNAPSHOT.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/log4j-1.2.17.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/netty-3.8.0.Final.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/protobuf-java-2.5.0.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/slf4j-api-1.7.5.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/slf4j-log4j12-1.7.5.jar:/home/kewang/git/libhbase/target/libhbase-1.0-SNAPSHOT/lib/zookeeper-3.4.5.jar
export HBASE_LIB_DIR=/home/kewang/hbase/lib
export HBASE_CONF_DIR=/home/kewang/hbase/conf
export LD_LIBRARY_PATH=/usr/lib/jvm/java-7-oracle/jre/lib/amd64/server

# MySQL environment variables

export LD_LIBRARY_PATH=/usr/lib/x86_64-linux-gnu

Run it

redis --hedis hedis.yml

Commands

GET

GET [connector-name]://[connector-command]

Example

# HBase example:
#
# get "kewang" rowkey at "user" table on "cdh1" connector
GET "cdh1://user:kewang"

# MySQL example:
#
# Query one record at "user" table on "mysqltest" connector
GET "mysqltest://select * from user limit 1"

SCAN, and so on.

TODO

Related with Redis

This is a modified version of Redis, maintaining by Kewang now.