Beispiel #1
0
// Implements storage.Interface.
func (h *etcdHelper) Delete(ctx context.Context, key string, out runtime.Object, preconditions *storage.Preconditions) error {
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	key = path.Join(h.pathPrefix, key)
	v, err := conversion.EnforcePtr(out)
	if err != nil {
		panic("unable to convert output object to pointer")
	}

	if preconditions == nil {
		startTime := time.Now()
		response, err := h.etcdKeysAPI.Delete(ctx, key, nil)
		metrics.RecordEtcdRequestLatency("delete", getTypeName(out), startTime)
		if !etcdutil.IsEtcdNotFound(err) {
			// if the object that existed prior to the delete is returned by etcd, update the out object.
			if err != nil || response.PrevNode != nil {
				_, _, err = h.extractObj(response, err, out, false, true)
			}
		}
		return toStorageErr(err, key, 0)
	}

	// Check the preconditions match.
	obj := reflect.New(v.Type()).Interface().(runtime.Object)
	for {
		_, node, res, err := h.bodyAndExtractObj(ctx, key, obj, false)
		if err != nil {
			return toStorageErr(err, key, 0)
		}
		if err := checkPreconditions(key, preconditions, obj); err != nil {
			return toStorageErr(err, key, 0)
		}
		index := uint64(0)
		if node != nil {
			index = node.ModifiedIndex
		} else if res != nil {
			index = res.Index
		}
		opt := etcd.DeleteOptions{PrevIndex: index}
		startTime := time.Now()
		response, err := h.etcdKeysAPI.Delete(ctx, key, &opt)
		metrics.RecordEtcdRequestLatency("delete", getTypeName(out), startTime)
		if etcdutil.IsEtcdTestFailed(err) {
			glog.Infof("deletion of %s failed because of a conflict, going to retry", key)
		} else {
			if !etcdutil.IsEtcdNotFound(err) {
				// if the object that existed prior to the delete is returned by etcd, update the out object.
				if err != nil || response.PrevNode != nil {
					_, _, err = h.extractObj(response, err, out, false, true)
				}
			}
			return toStorageErr(err, key, 0)
		}
	}
}
Beispiel #2
0
// Implements storage.Interface.
func (h *etcdHelper) List(ctx context.Context, key string, resourceVersion string, pred storage.SelectionPredicate, listObj runtime.Object) error {
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	trace := util.NewTrace("List " + getTypeName(listObj))
	defer trace.LogIfLong(400 * time.Millisecond)
	listPtr, err := meta.GetItemsPtr(listObj)
	if err != nil {
		return err
	}
	key = path.Join(h.pathPrefix, key)
	startTime := time.Now()
	trace.Step("About to list etcd node")
	nodes, index, err := h.listEtcdNode(ctx, key)
	trace.Step("Etcd node listed")
	metrics.RecordEtcdRequestLatency("list", getTypeName(listPtr), startTime)
	if err != nil {
		return err
	}
	if err := h.decodeNodeList(nodes, storage.SimpleFilter(pred), listPtr); err != nil {
		return err
	}
	trace.Step("Node list decoded")
	if err := h.versioner.UpdateList(listObj, index); err != nil {
		return err
	}
	return nil
}
Beispiel #3
0
// 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(ctx context.Context, key string, objPtr runtime.Object, ignoreNotFound bool) (body string, node *etcd.Node, res *etcd.Response, err error) {
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	startTime := time.Now()

	opts := &etcd.GetOptions{
		Quorum: h.quorum,
	}

	response, err := h.etcdKeysAPI.Get(ctx, key, opts)
	metrics.RecordEtcdRequestLatency("get", getTypeName(objPtr), startTime)
	if err != nil && !etcdutil.IsEtcdNotFound(err) {
		return "", nil, nil, toStorageErr(err, key, 0)
	}
	body, node, err = h.extractObj(response, err, objPtr, ignoreNotFound, false)
	return body, node, response, toStorageErr(err, key, 0)
}
Beispiel #4
0
// Implements storage.Interface.
func (h *etcdHelper) GetToList(ctx context.Context, key string, resourceVersion string, pred storage.SelectionPredicate, listObj runtime.Object) error {
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	trace := util.NewTrace("GetToList " + getTypeName(listObj))
	listPtr, err := meta.GetItemsPtr(listObj)
	if err != nil {
		return err
	}
	key = path.Join(h.pathPrefix, key)
	startTime := time.Now()
	trace.Step("About to read etcd node")

	opts := &etcd.GetOptions{
		Quorum: h.quorum,
	}
	response, err := h.etcdKeysAPI.Get(ctx, key, opts)
	trace.Step("Etcd node read")
	metrics.RecordEtcdRequestLatency("get", getTypeName(listPtr), startTime)
	if err != nil {
		if etcdutil.IsEtcdNotFound(err) {
			return nil
		}
		return toStorageErr(err, key, 0)
	}

	nodes := make([]*etcd.Node, 0)
	nodes = append(nodes, response.Node)

	if err := h.decodeNodeList(nodes, storage.SimpleFilter(pred), listPtr); err != nil {
		return err
	}
	trace.Step("Object decoded")
	if err := h.versioner.UpdateList(listObj, response.Index); err != nil {
		return err
	}
	return nil
}
Beispiel #5
0
// Implements storage.Interface.
func (h *etcdHelper) Create(ctx context.Context, key string, obj, out runtime.Object, ttl uint64) error {
	trace := util.NewTrace("etcdHelper::Create " + getTypeName(obj))
	defer trace.LogIfLong(250 * time.Millisecond)
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	key = path.Join(h.pathPrefix, key)
	data, err := runtime.Encode(h.codec, obj)
	trace.Step("Object encoded")
	if err != nil {
		return err
	}
	if version, err := h.versioner.ObjectResourceVersion(obj); err == nil && version != 0 {
		return errors.New("resourceVersion may not be set on objects to be created")
	}
	trace.Step("Version checked")

	startTime := time.Now()
	opts := etcd.SetOptions{
		TTL:       time.Duration(ttl) * time.Second,
		PrevExist: etcd.PrevNoExist,
	}
	response, err := h.etcdKeysAPI.Set(ctx, key, string(data), &opts)
	trace.Step("Object created")
	metrics.RecordEtcdRequestLatency("create", getTypeName(obj), startTime)
	if err != nil {
		return toStorageErr(err, key, 0)
	}
	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
}
Beispiel #6
0
// Implements storage.Interface.
func (h *etcdHelper) GuaranteedUpdate(
	ctx context.Context, key string, ptrToType runtime.Object, ignoreNotFound bool,
	preconditions *storage.Preconditions, tryUpdate storage.UpdateFunc, _ ...runtime.Object) error {
	// Ignore the suggestion about current object.
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	v, err := conversion.EnforcePtr(ptrToType)
	if err != nil {
		// Panic is appropriate, because this is a programming error.
		panic("need ptr to type")
	}
	key = path.Join(h.pathPrefix, key)
	for {
		obj := reflect.New(v.Type()).Interface().(runtime.Object)
		origBody, node, res, err := h.bodyAndExtractObj(ctx, key, obj, ignoreNotFound)
		if err != nil {
			return toStorageErr(err, key, 0)
		}
		if err := checkPreconditions(key, preconditions, obj); err != nil {
			return toStorageErr(err, key, 0)
		}
		meta := storage.ResponseMeta{}
		if node != nil {
			meta.TTL = node.TTL
			meta.ResourceVersion = node.ModifiedIndex
		}
		// Get the object to be written by calling tryUpdate.
		ret, newTTL, err := tryUpdate(obj, meta)
		if err != nil {
			return toStorageErr(err, key, 0)
		}

		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.Index
		}

		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
		}

		// Since update object may have a resourceVersion set, we need to clear it here.
		if err := h.versioner.UpdateObject(ret, 0); err != nil {
			return errors.New("resourceVersion cannot be set on objects store in etcd")
		}

		data, err := runtime.Encode(h.codec, ret)
		if err != nil {
			return err
		}

		// First time this key has been used, try creating new value.
		if index == 0 {
			startTime := time.Now()
			opts := etcd.SetOptions{
				TTL:       time.Duration(ttl) * time.Second,
				PrevExist: etcd.PrevNoExist,
			}
			response, err := h.etcdKeysAPI.Set(ctx, key, string(data), &opts)
			metrics.RecordEtcdRequestLatency("create", getTypeName(ptrToType), startTime)
			if etcdutil.IsEtcdNodeExist(err) {
				continue
			}
			_, _, err = h.extractObj(response, err, ptrToType, false, false)
			return toStorageErr(err, key, 0)
		}

		if string(data) == origBody {
			// If we don't send an update, we simply return the currently existing
			// version of the object.
			_, _, err := h.extractObj(res, nil, ptrToType, ignoreNotFound, false)
			return err
		}

		startTime := time.Now()
		// Swap origBody with data, if origBody is the latest etcd data.
		opts := etcd.SetOptions{
			PrevIndex: index,
			TTL:       time.Duration(ttl) * time.Second,
		}
		response, err := h.etcdKeysAPI.Set(ctx, key, string(data), &opts)
		metrics.RecordEtcdRequestLatency("compareAndSwap", getTypeName(ptrToType), startTime)
		if etcdutil.IsEtcdTestFailed(err) {
			// Try again.
			continue
		}
		_, _, err = h.extractObj(response, err, ptrToType, false, false)
		return toStorageErr(err, key, int64(index))
	}
}