Golang util.NewTrace函数代码示例

// ListPredicate returns a list of all the items matching m.
func (e *Etcd) ListPredicate(ctx api.Context, m generic.Matcher) (runtime.Object, error) {
	list := e.NewListFunc()
	trace := util.NewTrace("List " + reflect.TypeOf(list).String())
	defer trace.LogIfLong(600 * time.Millisecond)
	if name, ok := m.MatchesSingle(); ok {
		trace.Step("About to read single object")
		key, err := e.KeyFunc(ctx, name)
		if err != nil {
			return nil, err
		}
		err = e.Storage.GetToList(key, list)
		trace.Step("Object extracted")
		if err != nil {
			return nil, err
		}
	} else {
		trace.Step("About to list directory")
		err := e.Storage.List(e.KeyRootFunc(ctx), list)
		trace.Step("List extracted")
		if err != nil {
			return nil, err
		}
	}
	defer trace.Step("List filtered")
	return generic.FilterList(list, m, generic.DecoratorFunc(e.Decorator))
}

// ListPredicate returns a list of all the items matching m.
func (e *Etcd) ListPredicate(ctx api.Context, m generic.Matcher, options *api.ListOptions) (runtime.Object, error) {
	list := e.NewListFunc()
	trace := util.NewTrace("List " + reflect.TypeOf(list).String())
	filterFunc := e.filterAndDecorateFunction(m)
	defer trace.LogIfLong(600 * time.Millisecond)
	if name, ok := m.MatchesSingle(); ok {
		if key, err := e.KeyFunc(ctx, name); err == nil {
			trace.Step("About to read single object")
			err := e.Storage.GetToList(ctx, key, filterFunc, list)
			trace.Step("Object extracted")
			return list, etcderr.InterpretListError(err, e.EndpointName)
		}
		// if we cannot extract a key based on the current context, the optimization is skipped
	}

	trace.Step("About to list directory")
	if options == nil {
		options = &api.ListOptions{ResourceVersion: "0"}
	}
	version, err := storage.ParseWatchResourceVersion(options.ResourceVersion, e.EndpointName)
	if err != nil {
		return nil, err
	}
	err = e.Storage.List(ctx, e.KeyRootFunc(ctx), version, filterFunc, list)
	trace.Step("List extracted")
	return list, etcderr.InterpretListError(err, e.EndpointName)
}

// GetResource returns a function that handles retrieving a single resource from a rest.Storage object.
func GetResource(r rest.Getter, e rest.Exporter, scope RequestScope) restful.RouteFunction {
	return getResourceHandler(scope,
		func(ctx api.Context, name string, req *restful.Request) (runtime.Object, error) {
			// For performance tracking purposes.
			trace := util.NewTrace("Get " + req.Request.URL.Path)
			defer trace.LogIfLong(250 * time.Millisecond)

			// check for export
			if values := req.Request.URL.Query(); len(values) > 0 {
				// TODO: this is internal version, not unversioned
				exports := unversioned.ExportOptions{}
				if err := scope.ParameterCodec.DecodeParameters(values, unversioned.GroupVersion{Version: "v1"}, &exports); err != nil {
					return nil, err
				}
				if exports.Export {
					if e == nil {
						return nil, errors.NewBadRequest(fmt.Sprintf("export of %q is not supported", scope.Resource.Resource))
					}
					return e.Export(ctx, name, exports)
				}
			}

			return r.Get(ctx, name)
		})
}

// Implements storage.Interface.
func (h *etcdHelper) GetToList(key string, 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, 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) List(ctx context.Context, key string, resourceVersion string, filter storage.FilterFunc, listObj runtime.Object) error {
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	trace := util.NewTrace("List " + getTypeName(listObj))
	defer trace.LogIfLong(time.Second)
	listPtr, err := meta.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(ctx, 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 err := h.versioner.UpdateList(listObj, index); err != nil {
		return err
	}
	return nil
}

// Implements storage.Interface.
func (h *etcdHelper) List(key string, 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, 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 (c *Cacher) List(ctx context.Context, key string, resourceVersion string, pred SelectionPredicate, listObj runtime.Object) error {
	if resourceVersion == "" {
		// If resourceVersion is not specified, serve it from underlying
		// storage (for backward compatibility).
		return c.storage.List(ctx, key, resourceVersion, pred, listObj)
	}

	// If resourceVersion is specified, serve it from cache.
	// It's guaranteed that the returned value is at least that
	// fresh as the given resourceVersion.
	listRV, err := ParseListResourceVersion(resourceVersion)
	if err != nil {
		return err
	}

	trace := util.NewTrace(fmt.Sprintf("cacher %v: List", c.objectType.String()))
	defer trace.LogIfLong(500 * time.Millisecond)

	c.ready.wait()
	trace.Step("Ready")

	// List elements with at least 'listRV' from cache.
	listPtr, err := meta.GetItemsPtr(listObj)
	if err != nil {
		return err
	}
	listVal, err := conversion.EnforcePtr(listPtr)
	if err != nil || listVal.Kind() != reflect.Slice {
		return fmt.Errorf("need a pointer to slice, got %v", listVal.Kind())
	}
	filter := filterFunction(key, pred)

	objs, readResourceVersion, err := c.watchCache.WaitUntilFreshAndList(listRV, trace)
	if err != nil {
		return fmt.Errorf("failed to wait for fresh list: %v", err)
	}
	trace.Step(fmt.Sprintf("Listed %d items from cache", len(objs)))
	if len(objs) > listVal.Cap() && pred.Label.Empty() && pred.Field.Empty() {
		// Resize the slice appropriately, since we already know that none
		// of the elements will be filtered out.
		listVal.Set(reflect.MakeSlice(reflect.SliceOf(c.objectType.Elem()), 0, len(objs)))
		trace.Step("Resized result")
	}
	for _, obj := range objs {
		elem, ok := obj.(*storeElement)
		if !ok {
			return fmt.Errorf("non *storeElement returned from storage: %v", obj)
		}
		if filter(elem.Key, elem.Object) {
			listVal.Set(reflect.Append(listVal, reflect.ValueOf(elem.Object).Elem()))
		}
	}
	trace.Step(fmt.Sprintf("Filtered %d items", listVal.Len()))
	if c.versioner != nil {
		if err := c.versioner.UpdateList(listObj, readResourceVersion); err != nil {
			return err
		}
	}
	return nil
}

// ListPredicate returns a list of all the items matching m.
func (e *Etcd) ListPredicate(ctx api.Context, m generic.Matcher) (runtime.Object, error) {
	list := e.NewListFunc()
	trace := util.NewTrace("List " + reflect.TypeOf(list).String())
	filterFunc := e.filterAndDecorateFunction(m)
	defer trace.LogIfLong(600 * time.Millisecond)
	if name, ok := m.MatchesSingle(); ok {
		if key, err := e.KeyFunc(ctx, name); err == nil {
			trace.Step("About to read single object")
			err := e.Storage.GetToList(key, filterFunc, list)
			trace.Step("Object extracted")
			if err != nil {
				return nil, err
			}
			return list, nil
		}
		// if we cannot extract a key based on the current context, the optimization is skipped
	}

	trace.Step("About to list directory")
	err := e.Storage.List(e.KeyRootFunc(ctx), filterFunc, list)
	trace.Step("List extracted")
	if err != nil {
		return nil, err
	}
	return list, nil
}

// Schedule tries to schedule the given pod to one of node in the node list.
// If it succeeds, it will return the name of the node.
// If it fails, it will return a Fiterror error with reasons.
func (g *genericScheduler) Schedule(pod *api.Pod, nodeLister algorithm.NodeLister) (string, error) {
	var trace *util.Trace
	if pod != nil {
		trace = util.NewTrace(fmt.Sprintf("Scheduling %s/%s", pod.Namespace, pod.Name))
	} else {
		trace = util.NewTrace("Scheduling <nil> pod")
	}
	defer trace.LogIfLong(20 * time.Millisecond)

	nodes, err := nodeLister.List()
	if err != nil {
		return "", err
	}
	if len(nodes) == 0 {
		return "", ErrNoNodesAvailable
	}

	// Used for all fit and priority funcs.
	err = g.cache.UpdateNodeNameToInfoMap(g.cachedNodeInfoMap)
	if err != nil {
		return "", err
	}

	trace.Step("Computing predicates")
	filteredNodes, failedPredicateMap, err := findNodesThatFit(pod, g.cachedNodeInfoMap, nodes, g.predicates, g.extenders)
	if err != nil {
		return "", err
	}

	if len(filteredNodes) == 0 {
		return "", &FitError{
			Pod:              pod,
			FailedPredicates: failedPredicateMap,
		}
	}

	trace.Step("Prioritizing")
	meta := g.priorityMetaProducer(pod)
	priorityList, err := PrioritizeNodes(pod, g.cachedNodeInfoMap, meta, g.prioritizers, filteredNodes, g.extenders)
	if err != nil {
		return "", err
	}

	trace.Step("Selecting host")
	return g.selectHost(priorityList)
}

// GetResource returns a function that handles retrieving a single resource from a rest.Storage object.
func GetResource(r rest.Getter, scope RequestScope) restful.RouteFunction {
	return getResourceHandler(scope,
		func(ctx api.Context, name string, req *restful.Request) (runtime.Object, error) {
			// For performance tracking purposes.
			trace := util.NewTrace("Get " + req.Request.URL.Path)
			defer trace.LogIfLong(250 * time.Millisecond)
			return r.Get(ctx, name)
		})
}

// Implements storage.Interface.
func (c *Cacher) GetToList(ctx context.Context, key string, resourceVersion string, pred SelectionPredicate, listObj runtime.Object) error {
	if resourceVersion == "" {
		// If resourceVersion is not specified, serve it from underlying
		// storage (for backward compatibility).
		return c.storage.GetToList(ctx, key, resourceVersion, pred, listObj)
	}

	// If resourceVersion is specified, serve it from cache.
	// It's guaranteed that the returned value is at least that
	// fresh as the given resourceVersion.
	listRV, err := ParseListResourceVersion(resourceVersion)
	if err != nil {
		return err
	}

	trace := util.NewTrace(fmt.Sprintf("cacher %v: List", c.objectType.String()))
	defer trace.LogIfLong(500 * time.Millisecond)

	c.ready.wait()
	trace.Step("Ready")

	// List elements with at least 'listRV' from cache.
	listPtr, err := meta.GetItemsPtr(listObj)
	if err != nil {
		return err
	}
	listVal, err := conversion.EnforcePtr(listPtr)
	if err != nil || listVal.Kind() != reflect.Slice {
		return fmt.Errorf("need a pointer to slice, got %v", listVal.Kind())
	}
	filter := filterFunction(key, pred)

	obj, exists, readResourceVersion, err := c.watchCache.WaitUntilFreshAndGet(listRV, key, trace)
	if err != nil {
		return fmt.Errorf("failed to wait for fresh get: %v", err)
	}
	trace.Step("Got from cache")

	if exists {
		elem, ok := obj.(*storeElement)
		if !ok {
			return fmt.Errorf("non *storeElement returned from storage: %v", obj)
		}
		if filter(elem.Key, elem.Object) {
			listVal.Set(reflect.Append(listVal, reflect.ValueOf(elem.Object).Elem()))
		}
	}
	if c.versioner != nil {
		if err := c.versioner.UpdateList(listObj, readResourceVersion); err != nil {
			return err
		}
	}
	return nil
}

// decodeNodeList walks the tree of each node in the list and decodes into the specified object
func (h *etcdHelper) decodeNodeList(nodes []*etcd.Node, filter storage.FilterFunc, slicePtr interface{}) error {
	trace := util.NewTrace("decodeNodeList " + getTypeName(slicePtr))
	defer trace.LogIfLong(500 * time.Millisecond)
	v, err := conversion.EnforcePtr(slicePtr)
	if err != nil || v.Kind() != reflect.Slice {
		// This should not happen at runtime.
		panic("need ptr to slice")
	}
	for _, node := range nodes {
		if node.Dir {
			trace.Step("Decoding dir " + node.Key + " START")
			if err := h.decodeNodeList(node.Nodes, filter, slicePtr); err != nil {
				return err
			}
			trace.Step("Decoding dir " + node.Key + " END")
			continue
		}
		if obj, found := h.getFromCache(node.ModifiedIndex, filter); found {
			// obj != nil iff it matches the filter function.
			if obj != nil {
				v.Set(reflect.Append(v, reflect.ValueOf(obj).Elem()))
			}
		} else {
			obj, _, err := h.codec.Decode([]byte(node.Value), nil, reflect.New(v.Type().Elem()).Interface().(runtime.Object))
			if err != nil {
				return err
			}
			if h.versioner != nil {
				// being unable to set the version does not prevent the object from being extracted
				_ = h.versioner.UpdateObject(obj, node.Expiration, node.ModifiedIndex)
			}
			if filter(obj) {
				v.Set(reflect.Append(v, reflect.ValueOf(obj).Elem()))
			}
			if node.ModifiedIndex != 0 {
				h.addToCache(node.ModifiedIndex, obj)
			}
		}
	}
	trace.Step(fmt.Sprintf("Decoded %v nodes", len(nodes)))
	return nil
}

// Delete removes the item from etcd.
func (e *Etcd) Delete(ctx api.Context, name string, options *api.DeleteOptions) (runtime.Object, error) {
	key, err := e.KeyFunc(ctx, name)
	if err != nil {
		return nil, err
	}

	obj := e.NewFunc()
	trace := util.NewTrace("Delete " + reflect.TypeOf(obj).String())
	defer trace.LogIfLong(time.Second)
	trace.Step("About to read object")
	if err := e.Storage.Get(key, obj, false); err != nil {
		return nil, etcderr.InterpretDeleteError(err, e.EndpointName, name)
	}

	// support older consumers of delete by treating "nil" as delete immediately
	if options == nil {
		options = api.NewDeleteOptions(0)
	}
	graceful, pendingGraceful, err := rest.BeforeDelete(e.DeleteStrategy, ctx, obj, options)
	if err != nil {
		return nil, err
	}
	if pendingGraceful {
		return e.finalizeDelete(obj, false)
	}
	if graceful && *options.GracePeriodSeconds != 0 {
		trace.Step("Graceful deletion")
		out := e.NewFunc()
		if err := e.Storage.Set(key, obj, out, uint64(*options.GracePeriodSeconds)); err != nil {
			return nil, etcderr.InterpretUpdateError(err, e.EndpointName, name)
		}
		return e.finalizeDelete(out, true)
	}

	// delete immediately, or no graceful deletion supported
	out := e.NewFunc()
	trace.Step("About to delete object")
	if err := e.Storage.Delete(key, out); err != nil {
		return nil, etcderr.InterpretDeleteError(err, e.EndpointName, name)
	}
	return e.finalizeDelete(out, true)
}

// Get retrieves the item from etcd.
func (e *Etcd) Get(ctx api.Context, name string) (runtime.Object, error) {
	obj := e.NewFunc()
	trace := util.NewTrace("Get " + reflect.TypeOf(obj).String())
	defer trace.LogIfLong(time.Second)
	key, err := e.KeyFunc(ctx, name)
	if err != nil {
		return nil, err
	}
	trace.Step("About to read object")
	if err := e.Storage.Get(ctx, key, obj, false); err != nil {
		return nil, etcderr.InterpretGetError(err, e.EndpointName, name)
	}
	trace.Step("Object read")
	if e.Decorator != nil {
		if err := e.Decorator(obj); err != nil {
			return nil, err
		}
	}
	return obj, nil
}

func (c *cacheWatcher) add(event *watchCacheEvent) {
	// Try to send the event immediately, without blocking.
	select {
	case c.input <- *event:
		return
	default:
	}

	// OK, block sending, but only for up to 5 seconds.
	// cacheWatcher.add is called very often, so arrange
	// to reuse timers instead of constantly allocating.
	trace := util.NewTrace(
		fmt.Sprintf("cacheWatcher %v: waiting for add (initial result size %v)",
			reflect.TypeOf(event.Object).String(), len(c.result)))
	defer trace.LogIfLong(50 * time.Millisecond)

	const timeout = 5 * time.Second
	t, ok := timerPool.Get().(*time.Timer)
	if ok {
		t.Reset(timeout)
	} else {
		t = time.NewTimer(timeout)
	}
	defer timerPool.Put(t)

	select {
	case c.input <- *event:
		stopped := t.Stop()
		if !stopped {
			// Consume triggered (but not yet received) timer event
			// so that future reuse does not get a spurious timeout.
			<-t.C
		}
	case <-t.C:
		// This means that we couldn't send event to that watcher.
		// Since we don't want to block on it infinitely,
		// we simply terminate it.
		c.forget(false)
		c.stop()
	}
}