// Implements storage.Interface.
func (h *etcdHelper) List(key string, filter storage.FilterFunc, listObj runtime.Object) error {
trace := util.NewTrace("List " + getTypeName(listObj))
defer trace.LogIfLong(time.Second)
listPtr, err := runtime.GetItemsPtr(listObj)
if err != nil {
return err
}
key = h.prefixEtcdKey(key)
startTime := time.Now()
trace.Step("About to list etcd node")
nodes, index, err := h.listEtcdNode(key)
metrics.RecordEtcdRequestLatency("list", getTypeName(listPtr), startTime)
trace.Step("Etcd node listed")
if err != nil {
return err
}
if err := h.decodeNodeList(nodes, filter, listPtr); err != nil {
return err
}
trace.Step("Node list decoded")
if h.versioner != nil {
if err := h.versioner.UpdateList(listObj, index); err != nil {
return err
}
}
return nil
}
// Implements storage.Interface.
func (h *etcdHelper) Create(key string, obj, out runtime.Object, ttl uint64) error {
key = h.prefixEtcdKey(key)
data, err := h.codec.Encode(obj)
if err != nil {
return err
}
if h.versioner != nil {
if version, err := h.versioner.ObjectResourceVersion(obj); err == nil && version != 0 {
return errors.New("resourceVersion may not be set on objects to be created")
}
}
startTime := time.Now()
response, err := h.client.Create(key, string(data), ttl)
metrics.RecordEtcdRequestLatency("create", getTypeName(obj), startTime)
if err != nil {
return err
}
if out != nil {
if _, err := conversion.EnforcePtr(out); err != nil {
panic("unable to convert output object to pointer")
}
_, _, err = h.extractObj(response, err, out, false, false)
}
return err
}
// Implements storage.Interface.
func (h *etcdHelper) GetToList(key string, filter storage.FilterFunc, listObj runtime.Object) error {
trace := util.NewTrace("GetToList " + getTypeName(listObj))
listPtr, err := runtime.GetItemsPtr(listObj)
if err != nil {
return err
}
key = h.prefixEtcdKey(key)
startTime := time.Now()
trace.Step("About to read etcd node")
response, err := h.client.Get(key, false, false)
metrics.RecordEtcdRequestLatency("get", getTypeName(listPtr), startTime)
trace.Step("Etcd node read")
if err != nil {
if IsEtcdNotFound(err) {
return nil
}
return err
}
nodes := make([]*etcd.Node, 0)
nodes = append(nodes, response.Node)
if err := h.decodeNodeList(nodes, filter, listPtr); err != nil {
return err
}
trace.Step("Object decoded")
if h.versioner != nil {
if err := h.versioner.UpdateList(listObj, response.EtcdIndex); err != nil {
return err
}
}
return nil
}
// Implements storage.Interface.
func (h *etcdHelper) Set(ctx context.Context, key string, obj, out runtime.Object, ttl uint64) error {
if ctx == nil {
glog.Errorf("Context is nil")
}
var response *etcd.Response
data, err := h.codec.Encode(obj)
if err != nil {
return err
}
key = h.prefixEtcdKey(key)
create := true
if h.versioner != nil {
if version, err := h.versioner.ObjectResourceVersion(obj); err == nil && version != 0 {
create = false
startTime := time.Now()
response, err = h.client.CompareAndSwap(key, string(data), ttl, "", version)
metrics.RecordEtcdRequestLatency("compareAndSwap", getTypeName(obj), startTime)
if err != nil {
return err
}
}
}
if create {
// Create will fail if a key already exists.
startTime := time.Now()
response, err = h.client.Create(key, string(data), ttl)
metrics.RecordEtcdRequestLatency("create", getTypeName(obj), startTime)
}
if err != nil {
return err
}
if out != nil {
if _, err := conversion.EnforcePtr(out); err != nil {
panic("unable to convert output object to pointer")
}
_, _, err = h.extractObj(response, err, out, false, false)
}
return err
}
// bodyAndExtractObj performs the normal Get path to etcd, returning the parsed node and response for additional information
// about the response, like the current etcd index and the ttl.
func (h *etcdHelper) bodyAndExtractObj(key string, objPtr runtime.Object, ignoreNotFound bool) (body string, node *etcd.Node, res *etcd.Response, err error) {
startTime := time.Now()
response, err := h.client.Get(key, false, false)
metrics.RecordEtcdRequestLatency("get", getTypeName(objPtr), startTime)
if err != nil && !IsEtcdNotFound(err) {
return "", nil, nil, err
}
body, node, err = h.extractObj(response, err, objPtr, ignoreNotFound, false)
return body, node, response, err
}
// Implements storage.Interface.
func (h *etcdHelper) Delete(key string, out runtime.Object) error {
key = h.prefixEtcdKey(key)
if _, err := conversion.EnforcePtr(out); err != nil {
panic("unable to convert output object to pointer")
}
startTime := time.Now()
response, err := h.client.Delete(key, false)
metrics.RecordEtcdRequestLatency("delete", getTypeName(out), startTime)
if !IsEtcdNotFound(err) {
// if the object that existed prior to the delete is returned by etcd, update out.
if err != nil || response.PrevNode != nil {
_, _, err = h.extractObj(response, err, out, false, true)
}
}
return err
}
// Implements storage.Interface.
func (h *etcdHelper) GuaranteedUpdate(key string, ptrToType runtime.Object, ignoreNotFound bool, tryUpdate storage.UpdateFunc) error {
v, err := conversion.EnforcePtr(ptrToType)
if err != nil {
// Panic is appropriate, because this is a programming error.
panic("need ptr to type")
}
key = h.prefixEtcdKey(key)
for {
obj := reflect.New(v.Type()).Interface().(runtime.Object)
origBody, node, res, err := h.bodyAndExtractObj(key, obj, ignoreNotFound)
if err != nil {
return err
}
meta := storage.ResponseMeta{}
if node != nil {
meta.TTL = node.TTL
if node.Expiration != nil {
meta.Expiration = node.Expiration
}
meta.ResourceVersion = node.ModifiedIndex
}
// Get the object to be written by calling tryUpdate.
ret, newTTL, err := tryUpdate(obj, meta)
if err != nil {
return err
}
index := uint64(0)
ttl := uint64(0)
if node != nil {
index = node.ModifiedIndex
if node.TTL != 0 {
ttl = uint64(node.TTL)
}
if node.Expiration != nil && ttl == 0 {
ttl = 1
}
} else if res != nil {
index = res.EtcdIndex
}
if newTTL != nil {
if ttl != 0 && *newTTL == 0 {
// TODO: remove this after we have verified this is no longer an issue
glog.V(4).Infof("GuaranteedUpdate is clearing TTL for %q, may not be intentional", key)
}
ttl = *newTTL
}
data, err := h.codec.Encode(ret)
if err != nil {
return err
}
// First time this key has been used, try creating new value.
if index == 0 {
startTime := time.Now()
response, err := h.client.Create(key, string(data), ttl)
metrics.RecordEtcdRequestLatency("create", getTypeName(ptrToType), startTime)
if IsEtcdNodeExist(err) {
continue
}
_, _, err = h.extractObj(response, err, ptrToType, false, false)
return err
}
if string(data) == origBody {
return nil
}
startTime := time.Now()
// Swap origBody with data, if origBody is the latest etcd data.
response, err := h.client.CompareAndSwap(key, string(data), ttl, origBody, index)
metrics.RecordEtcdRequestLatency("compareAndSwap", getTypeName(ptrToType), startTime)
if IsEtcdTestFailed(err) {
// Try again.
continue
}
_, _, err = h.extractObj(response, err, ptrToType, false, false)
return err
}
}