func acquire(c *etcd.Client, key, value string, ttl uint64) (uint64, error) {
resp, err := c.Create(key, value, ttl)
if err != nil {
return 0, err
}
return resp.EtcdIndex, nil
}
// acquireOrRenewLease either races to acquire a new master lease, or update the existing master's lease
// returns true if we have the lease, and an error if one occurs.
// TODO: use the master election utility once it is merged in.
func (c *Config) acquireOrRenewLease(etcdClient *etcd.Client) (bool, error) {
result, err := etcdClient.Get(c.key, false, false)
if err != nil {
if tools.IsEtcdNotFound(err) {
// there is no current master, try to become master, create will fail if the key already exists
_, err := etcdClient.Create(c.key, c.whoami, c.ttl)
if err != nil {
return false, err
}
c.lastLease = time.Now()
return true, nil
}
return false, err
}
if result.Node.Value == c.whoami {
glog.Infof("key already exists, we are the master (%s)", result.Node.Value)
// we extend our lease @ 1/2 of the existing TTL, this ensures the master doesn't flap around
if result.Node.Expiration.Sub(time.Now()) < time.Duration(c.ttl/2)*time.Second {
_, err := etcdClient.CompareAndSwap(c.key, c.whoami, c.ttl, c.whoami, result.Node.ModifiedIndex)
if err != nil {
return false, err
}
}
c.lastLease = time.Now()
return true, nil
}
glog.Infof("key already exists, the master is %s, sleeping.", result.Node.Value)
return false, nil
}
func MustCreate(c *etcd.Client, logger *log.Logger, key, value string, ttl uint64) *etcd.Response {
resp, err := c.Create(key, value, ttl)
if err != nil {
logger.Panicf("Create failed. Key: %s, err: %v", key, err)
}
return resp
}
// makeCommandFunc executes the "make" command.
func makeCommandFunc(cmd *cobra.Command, args []string, client *etcd.Client) (*etcd.Response, error) {
if len(args) == 0 {
return nil, errors.New("Key required")
}
key := args[0]
value, err := argOrStdin(args, os.Stdin, 1)
if err != nil {
return nil, errors.New("Value required")
}
ttl := mkTtlFlag
return client.Create(key, value, uint64(ttl))
}
func TryOccupyTask(client *etcd.Client, name string, taskID uint64, connection string) (bool, error) {
_, err := client.Create(TaskHealthyPath(name, taskID), "health", 3)
if err != nil {
if strings.Contains(err.Error(), "Key already exists") {
return false, nil
}
return false, err
}
idStr := strconv.FormatUint(taskID, 10)
client.Delete(FreeTaskPath(name, idStr), false)
_, err = client.Set(TaskMasterPath(name, taskID), connection, 0)
if err != nil {
return false, err
}
return true, nil
}
// Send etcd Data and output.
func setETCD(client *etcd.Client, full_key, value string) {
log.Printf("Setting %s => %s \n", full_key, value)
client.Create(full_key, value, 0)
}