Glock is used to achieve consensus between different hosts using a persistent stores.
The cassandra implementation is based on the article here: https://www.datastax.com/dev/blog/consensus-on-cassandra
CREATE KEYSPACE test WITH REPLICATION = { 'class' : 'SimpleStrategy', 'replication_factor': 1};
CREATE TABLE test.lock (id text, owner text, PRIMARY KEY (id)) WITH default_time_to_live = 5;import (
"github.com/gocql/gocql"
"github.com/yehohanan7/glock"
)
session := //initialize a cassandra session using gocql
config := glock.Config{
"host1",
time.NewTicker(2 * time.Second),
glock.NewCassandraStore(session),
notifyCh,
stopCh,
}
go glock.Start(config)
for {
select {
case state := <-notifyCh:
if state == "master" {
fmt.Println("became master")
}
if state == "slave" {
fmt.Println("became slave")
}
}
}