[VOL-2193] Create mocks for Kafka Client and Etcd
This commit consists of:
1) A kafka client mock that implements the kafka client interface
under voltha-lib-go/pkg/kafka/client.go
2) An embedded Etcd server that runs in-process and represents an
Etcd server.
Change-Id: I52a36132568e08c596bb4136918bebcb654a3b99
diff --git a/vendor/go.etcd.io/etcd/etcdserver/api/v2store/node.go b/vendor/go.etcd.io/etcd/etcdserver/api/v2store/node.go
new file mode 100644
index 0000000..38a6984
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/etcdserver/api/v2store/node.go
@@ -0,0 +1,396 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package v2store
+
+import (
+ "path"
+ "sort"
+ "time"
+
+ "go.etcd.io/etcd/etcdserver/api/v2error"
+
+ "github.com/jonboulle/clockwork"
+)
+
+// explanations of Compare function result
+const (
+ CompareMatch = iota
+ CompareIndexNotMatch
+ CompareValueNotMatch
+ CompareNotMatch
+)
+
+var Permanent time.Time
+
+// 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
+
+ CreatedIndex uint64
+ ModifiedIndex uint64
+
+ Parent *node `json:"-"` // should not encode this field! avoid circular dependency.
+
+ ExpireTime time.Time
+ Value string // for key-value pair
+ Children map[string]*node // for directory
+
+ // A reference to the store this node is attached to.
+ store *store
+}
+
+// newKV creates a Key-Value pair
+func newKV(store *store, nodePath string, value string, createdIndex uint64, parent *node, expireTime time.Time) *node {
+ return &node{
+ Path: nodePath,
+ CreatedIndex: createdIndex,
+ ModifiedIndex: createdIndex,
+ Parent: parent,
+ store: store,
+ ExpireTime: expireTime,
+ Value: value,
+ }
+}
+
+// newDir creates a directory
+func newDir(store *store, nodePath string, createdIndex uint64, parent *node, expireTime time.Time) *node {
+ return &node{
+ Path: nodePath,
+ CreatedIndex: createdIndex,
+ ModifiedIndex: createdIndex,
+ Parent: parent,
+ ExpireTime: expireTime,
+ Children: make(map[string]*node),
+ store: 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] == '_'
+}
+
+// IsPermanent function checks if the node is a permanent one.
+func (n *node) IsPermanent() bool {
+ // we use a uninitialized time.Time to indicate the node is a
+ // permanent one.
+ // the uninitialized time.Time should equal zero.
+ return n.ExpireTime.IsZero()
+}
+
+// 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
+}
+
+// Read function gets the value of the node.
+// If the receiver node is not a key-value pair, a "Not A File" error will be returned.
+func (n *node) Read() (string, *v2error.Error) {
+ if n.IsDir() {
+ return "", v2error.NewError(v2error.EcodeNotFile, "", n.store.CurrentIndex)
+ }
+
+ return n.Value, nil
+}
+
+// Write function set the value of the node to the given value.
+// If the receiver node is a directory, a "Not A File" error will be returned.
+func (n *node) Write(value string, index uint64) *v2error.Error {
+ if n.IsDir() {
+ return v2error.NewError(v2error.EcodeNotFile, "", n.store.CurrentIndex)
+ }
+
+ n.Value = value
+ n.ModifiedIndex = index
+
+ return nil
+}
+
+func (n *node) expirationAndTTL(clock clockwork.Clock) (*time.Time, int64) {
+ if !n.IsPermanent() {
+ /* compute ttl as:
+ ceiling( (expireTime - timeNow) / nanosecondsPerSecond )
+ which ranges from 1..n
+ rather than as:
+ ( (expireTime - timeNow) / nanosecondsPerSecond ) + 1
+ which ranges 1..n+1
+ */
+ ttlN := n.ExpireTime.Sub(clock.Now())
+ ttl := ttlN / time.Second
+ if (ttlN % time.Second) > 0 {
+ ttl++
+ }
+ t := n.ExpireTime.UTC()
+ return &t, int64(ttl)
+ }
+ return nil, 0
+}
+
+// List function return a slice of nodes under the receiver node.
+// If the receiver node is not a directory, a "Not A Directory" error will be returned.
+func (n *node) List() ([]*node, *v2error.Error) {
+ if !n.IsDir() {
+ return nil, v2error.NewError(v2error.EcodeNotDir, "", n.store.CurrentIndex)
+ }
+
+ nodes := make([]*node, len(n.Children))
+
+ i := 0
+ for _, node := range n.Children {
+ nodes[i] = node
+ i++
+ }
+
+ return nodes, nil
+}
+
+// GetChild function returns the child node under the directory node.
+// On success, it returns the file node
+func (n *node) GetChild(name string) (*node, *v2error.Error) {
+ if !n.IsDir() {
+ return nil, v2error.NewError(v2error.EcodeNotDir, n.Path, n.store.CurrentIndex)
+ }
+
+ child, ok := n.Children[name]
+
+ if ok {
+ return child, nil
+ }
+
+ return nil, nil
+}
+
+// Add function adds a node to the receiver node.
+// If the receiver is not a directory, a "Not A Directory" error will be returned.
+// If there is an existing node with the same name under the directory, a "Already Exist"
+// error will be returned
+func (n *node) Add(child *node) *v2error.Error {
+ if !n.IsDir() {
+ return v2error.NewError(v2error.EcodeNotDir, "", n.store.CurrentIndex)
+ }
+
+ _, name := path.Split(child.Path)
+
+ if _, ok := n.Children[name]; ok {
+ return v2error.NewError(v2error.EcodeNodeExist, "", n.store.CurrentIndex)
+ }
+
+ n.Children[name] = child
+
+ return nil
+}
+
+// Remove function remove the node.
+func (n *node) Remove(dir, recursive bool, callback func(path string)) *v2error.Error {
+ 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 {
+ delete(n.Parent.Children, name)
+ }
+
+ if callback != nil {
+ callback(n.Path)
+ }
+
+ if !n.IsPermanent() {
+ n.store.ttlKeyHeap.remove(n)
+ }
+
+ return nil
+ }
+
+ if !dir {
+ // cannot delete a directory without dir set to true
+ return v2error.NewError(v2error.EcodeNotFile, n.Path, n.store.CurrentIndex)
+ }
+
+ if len(n.Children) != 0 && !recursive {
+ // cannot delete a directory if it is not empty and the operation
+ // is not recursive
+ return v2error.NewError(v2error.EcodeDirNotEmpty, n.Path, n.store.CurrentIndex)
+ }
+
+ for _, child := range n.Children { // delete all children
+ child.Remove(true, true, callback)
+ }
+
+ // delete self
+ _, name := path.Split(n.Path)
+ if n.Parent != nil && n.Parent.Children[name] == n {
+ delete(n.Parent.Children, name)
+
+ if callback != nil {
+ callback(n.Path)
+ }
+
+ if !n.IsPermanent() {
+ n.store.ttlKeyHeap.remove(n)
+ }
+ }
+
+ return nil
+}
+
+func (n *node) Repr(recursive, sorted bool, clock clockwork.Clock) *NodeExtern {
+ if n.IsDir() {
+ node := &NodeExtern{
+ Key: n.Path,
+ Dir: true,
+ ModifiedIndex: n.ModifiedIndex,
+ CreatedIndex: n.CreatedIndex,
+ }
+ node.Expiration, node.TTL = n.expirationAndTTL(clock)
+
+ if !recursive {
+ return node
+ }
+
+ children, _ := n.List()
+ node.Nodes = make(NodeExterns, len(children))
+
+ // we do not use the index in the children slice directly
+ // we need to skip the hidden one
+ i := 0
+
+ for _, child := range children {
+
+ if child.IsHidden() { // get will not list hidden node
+ continue
+ }
+
+ node.Nodes[i] = child.Repr(recursive, sorted, clock)
+
+ i++
+ }
+
+ // eliminate hidden nodes
+ node.Nodes = node.Nodes[:i]
+ if sorted {
+ sort.Sort(node.Nodes)
+ }
+
+ return node
+ }
+
+ // since n.Value could be changed later, so we need to copy the value out
+ value := n.Value
+ node := &NodeExtern{
+ Key: n.Path,
+ Value: &value,
+ ModifiedIndex: n.ModifiedIndex,
+ CreatedIndex: n.CreatedIndex,
+ }
+ node.Expiration, node.TTL = n.expirationAndTTL(clock)
+ return node
+}
+
+func (n *node) UpdateTTL(expireTime time.Time) {
+ if !n.IsPermanent() {
+ if expireTime.IsZero() {
+ // from ttl to permanent
+ n.ExpireTime = expireTime
+ // remove from ttl heap
+ n.store.ttlKeyHeap.remove(n)
+ return
+ }
+
+ // update ttl
+ n.ExpireTime = expireTime
+ // update ttl heap
+ n.store.ttlKeyHeap.update(n)
+ return
+ }
+
+ if expireTime.IsZero() {
+ return
+ }
+
+ // from permanent to ttl
+ n.ExpireTime = expireTime
+ // push into ttl heap
+ n.store.ttlKeyHeap.push(n)
+}
+
+// Compare function compares node index and value with provided ones.
+// second result value explains result and equals to one of Compare.. constants
+func (n *node) Compare(prevValue string, prevIndex uint64) (ok bool, which int) {
+ indexMatch := prevIndex == 0 || n.ModifiedIndex == prevIndex
+ valueMatch := prevValue == "" || n.Value == prevValue
+ ok = valueMatch && indexMatch
+ switch {
+ case valueMatch && indexMatch:
+ which = CompareMatch
+ case indexMatch && !valueMatch:
+ which = CompareValueNotMatch
+ case valueMatch && !indexMatch:
+ which = CompareIndexNotMatch
+ default:
+ which = CompareNotMatch
+ }
+ return ok, which
+}
+
+// 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() {
+ newkv := newKV(n.store, n.Path, n.Value, n.CreatedIndex, n.Parent, n.ExpireTime)
+ newkv.ModifiedIndex = n.ModifiedIndex
+ return newkv
+ }
+
+ clone := newDir(n.store, n.Path, n.CreatedIndex, n.Parent, n.ExpireTime)
+ clone.ModifiedIndex = n.ModifiedIndex
+
+ for key, child := range n.Children {
+ clone.Children[key] = child.Clone()
+ }
+
+ return clone
+}
+
+// recoverAndclean function help to do recovery.
+// Two things need to be done: 1. recovery structure; 2. delete expired nodes
+//
+// If the node is a directory, it will help recover children's parent pointer and recursively
+// call this function on its children.
+// We check the expire last since we need to recover the whole structure first and add all the
+// notifications into the event history.
+func (n *node) recoverAndclean() {
+ if n.IsDir() {
+ for _, child := range n.Children {
+ child.Parent = n
+ child.store = n.store
+ child.recoverAndclean()
+ }
+ }
+
+ if !n.ExpireTime.IsZero() {
+ n.store.ttlKeyHeap.push(n)
+ }
+}