Mirroristas/etcd
2
0
Fork 0
mirror of https://github.com/etcd-io/etcd.git synced 2024-09-27 06:25:44 +00:00
Code Issues Packages Projects Releases Wiki Activity

refactor node.go; use once

Browse Source
This commit is contained in:
Xiang Li
2013-10-07 23:12:13 -07:00
parent a71838a59b
commit a07802a347
2 changed files with 124 additions and 100 deletions
Download Patch File Download Diff File Expand all files Collapse all files

222
store/node.go
View File

@@ -3,6 +3,7 @@ package store
import (
"path"
"sort"
"sync"
"time"
etcdErr "github.com/coreos/etcd/error"
@@ -17,22 +18,37 @@ const (
removed
)
// Node is the basic element in the store system.
// A key-value pair will have a string value
// A directory will have a children map
type Node struct {
Path string
Path string
CreateIndex uint64
CreateTerm uint64
ModifiedIndex uint64
ModifiedTerm uint64
Parent *Node `json:"-"`
ExpireTime time.Time
ACL string
Value string // for key-value pair
Children map[string]*Node // for directory
status int
stopExpire chan bool // stop expire routine channel
Parent *Node `json:"-"` // should not encode this field! avoid cyclical dependency.
ExpireTime time.Time
ACL string
Value string // for key-value pair
Children map[string]*Node // for directory
// a ttl node will have an expire routine associated with it.
// we need a channel to stop that routine when the expiration changes.
stopExpire chan bool
// ensure we only delete the node once
// expire and remove may try to delete a node twice
once sync.Once
}
func newFile(nodePath string, value string, createIndex uint64, createTerm uint64, parent *Node, ACL string, expireTime time.Time) *Node {
// newKV creates a Key-Value pair
func newKV(nodePath string, value string, createIndex uint64,
createTerm uint64, parent *Node, ACL string, expireTime time.Time) *Node {
return &Node{
Path: nodePath,
CreateIndex: createIndex,
@@ -47,7 +63,10 @@ func newFile(nodePath string, value string, createIndex uint64, createTerm uint6
}
}
func newDir(nodePath string, createIndex uint64, createTerm uint64, parent *Node, ACL string, expireTime time.Time) *Node {
// newDir creates a directory
func newDir(nodePath string, createIndex uint64, createTerm uint64,
parent *Node, ACL string, expireTime time.Time) *Node {
return &Node{
Path: nodePath,
CreateIndex: createIndex,
@@ -60,36 +79,79 @@ func newDir(nodePath string, createIndex uint64, createTerm uint64, parent *Node
}
}
// Remove function remove the node.
// If the node is a directory and recursive is true, the function will recursively remove
// add nodes under the receiver node.
func (n *Node) Remove(recursive bool, callback func(path string)) *etcdErr.Error {
if n.status == removed { // check race between remove and expire
return nil
// IsHidden function checks if the node is a hidden node. A hidden node
// will begin with '_'
// A hidden node will not be shown via get command under a directory
// For example if we have /foo/_hidden and /foo/notHidden, get "/foo"
// will only return /foo/notHidden
func (n *Node) IsHidden() bool {
_, name := path.Split(n.Path)
return name[0] == '_'
}
// IsPermanent function checks if the node is a permanent one.
func (n *Node) IsPermanent() bool {
return n.ExpireTime.Sub(Permanent) == 0
}
// IsExpired function checks if the node has been expired.
func (n *Node) IsExpired() (bool, time.Duration) {
if n.IsPermanent() {
return false, 0
}
if !n.IsDir() { // file node: key-value pair
duration := n.ExpireTime.Sub(time.Now())
if duration <= 0 {
return true, 0
}
return false, duration
}
// IsDir function checks whether the node is a directory.
// If the node is a directory, the function will return true.
// Otherwise the function will return false.
func (n *Node) IsDir() bool {
return !(n.Children == nil)
}
// Remove function remove the node.
func (n *Node) Remove(recursive bool, callback func(path string)) *etcdErr.Error {
if n.IsDir() && !recursive {
// cannot delete a directory without set recursive to true
return etcdErr.NewError(etcdErr.EcodeNotFile, "", UndefIndex, UndefTerm)
}
onceBody := func() {
n.internalRemove(recursive, callback)
}
// this function might be entered multiple times by expire and delete
// every node will only be deleted once.
n.once.Do(onceBody)
return nil
}
// internalRemove function will be called by remove()
func (n *Node) internalRemove(recursive bool, callback func(path string)) {
if !n.IsDir() { // key-value pair
_, name := path.Split(n.Path)
// find its parent and remove the node from the map
if n.Parent != nil && n.Parent.Children[name] == n {
// This is the only pointer to Node object
// Handled by garbage collector
delete(n.Parent.Children, name)
if callback != nil {
callback(n.Path)
}
n.stopExpire <- true
n.status = removed
}
return nil
}
if callback != nil {
callback(n.Path)
}
if !recursive {
return etcdErr.NewError(etcdErr.EcodeNotFile, "", UndefIndex, UndefTerm)
// the stop channel has a buffer. just send to it!
n.stopExpire <- true
return
}
for _, child := range n.Children { // delete all children
@@ -106,10 +168,7 @@ func (n *Node) Remove(recursive bool, callback func(path string)) *etcdErr.Error
}
n.stopExpire <- true
n.status = removed
}
return nil
}
// Read function gets the value of the node.
@@ -192,36 +251,6 @@ func (n *Node) Add(child *Node) *etcdErr.Error {
return nil
}
// Clone function clone the node recursively and return the new node.
// If the node is a directory, it will clone all the content under this directory.
// If the node is a key-value pair, it will clone the pair.
func (n *Node) Clone() *Node {
if !n.IsDir() {
return newFile(n.Path, n.Value, n.CreateIndex, n.CreateTerm, n.Parent, n.ACL, n.ExpireTime)
}
clone := newDir(n.Path, n.CreateIndex, n.CreateTerm, n.Parent, n.ACL, n.ExpireTime)
for key, child := range n.Children {
clone.Children[key] = child.Clone()
}
return clone
}
func (n *Node) recoverAndclean(s *Store) {
if n.IsDir() {
for _, child := range n.Children {
child.Parent = n
child.recoverAndclean(s)
}
}
n.stopExpire = make(chan bool, 1)
n.Expire(s)
}
// Expire function will test if the node is expired.
// if the node is already expired, delete the node and return.
// if the node is permemant (this shouldn't happen), return at once.
@@ -268,41 +297,6 @@ func (n *Node) Expire(s *Store) {
}()
}
// IsHidden function checks if the node is a hidden node. A hidden node
// will begin with '_'
// A hidden node will not be shown via get command under a directory
// For example if we have /foo/_hidden and /foo/notHidden, get "/foo"
// will only return /foo/notHidden
func (n *Node) IsHidden() bool {
_, name := path.Split(n.Path)
return name[0] == '_'
}
func (n *Node) IsPermanent() bool {
return n.ExpireTime.Sub(Permanent) == 0
}
func (n *Node) IsExpired() (bool, time.Duration) {
if n.IsPermanent() {
return false, 0
}
duration := n.ExpireTime.Sub(time.Now())
if duration <= 0 {
return true, 0
}
return false, duration
}
// IsDir function checks whether the node is a directory.
// If the node is a directory, the function will return true.
// Otherwise the function will return false.
func (n *Node) IsDir() bool {
return !(n.Children == nil)
}
func (n *Node) Pair(recurisive, sorted bool) KeyValuePair {
if n.IsDir() {
pair := KeyValuePair{
@@ -364,3 +358,33 @@ func (n *Node) UpdateTTL(expireTime time.Time, s *Store) {
n.Expire(s)
}
}
// Clone function clone the node recursively and return the new node.
// If the node is a directory, it will clone all the content under this directory.
// If the node is a key-value pair, it will clone the pair.
func (n *Node) Clone() *Node {
if !n.IsDir() {
return newKV(n.Path, n.Value, n.CreateIndex, n.CreateTerm, n.Parent, n.ACL, n.ExpireTime)
}
clone := newDir(n.Path, n.CreateIndex, n.CreateTerm, n.Parent, n.ACL, n.ExpireTime)
for key, child := range n.Children {
clone.Children[key] = child.Clone()
}
return clone
}
func (n *Node) recoverAndclean(s *Store) {
if n.IsDir() {
for _, child := range n.Children {
child.Parent = n
child.recoverAndclean(s)
}
}
n.stopExpire = make(chan bool, 1)
n.Expire(s)
}

2
store/store.go
View File

@@ -344,7 +344,7 @@ func (s *Store) internalCreate(nodePath string, value string, incrementalSuffix
if len(value) != 0 { // create file
e.Value = value
n = newFile(nodePath, value, s.Index, s.Term, d, "", expireTime)
n = newKV(nodePath, value, s.Index, s.Term, d, "", expireTime)
} else { // create directory
e.Dir = true