Updates for jaeger tracing client.

vendor/github.com/uber/jaeger-client-go/internal/baggage/remote/options.go

@@ -0,0 +1,101 @@
+// Copyright (c) 2017 Uber Technologies, Inc.
+//
+// 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 remote
+
+import (
+	"time"
+
+	"github.com/uber/jaeger-client-go"
+)
+
+const (
+	defaultMaxValueLength  = 2048
+	defaultRefreshInterval = time.Minute
+	defaultHostPort        = "localhost:5778"
+)
+
+// Option is a function that sets some option on the RestrictionManager
+type Option func(options *options)
+
+// Options is a factory for all available options
+var Options options
+
+type options struct {
+	denyBaggageOnInitializationFailure bool
+	metrics                            *jaeger.Metrics
+	logger                             jaeger.Logger
+	hostPort                           string
+	refreshInterval                    time.Duration
+}
+
+// DenyBaggageOnInitializationFailure creates an Option that determines the startup failure mode of RestrictionManager.
+// If DenyBaggageOnInitializationFailure is true, RestrictionManager will not allow any baggage to be written until baggage
+// restrictions have been retrieved from agent.
+// If DenyBaggageOnInitializationFailure is false, RestrictionManager will allow any baggage to be written until baggage
+// restrictions have been retrieved from agent.
+func (options) DenyBaggageOnInitializationFailure(b bool) Option {
+	return func(o *options) {
+		o.denyBaggageOnInitializationFailure = b
+	}
+}
+
+// Metrics creates an Option that initializes Metrics on the RestrictionManager, which is used to emit statistics.
+func (options) Metrics(m *jaeger.Metrics) Option {
+	return func(o *options) {
+		o.metrics = m
+	}
+}
+
+// Logger creates an Option that sets the logger used by the RestrictionManager.
+func (options) Logger(logger jaeger.Logger) Option {
+	return func(o *options) {
+		o.logger = logger
+	}
+}
+
+// HostPort creates an Option that sets the hostPort of the local agent that contains the baggage restrictions.
+func (options) HostPort(hostPort string) Option {
+	return func(o *options) {
+		o.hostPort = hostPort
+	}
+}
+
+// RefreshInterval creates an Option that sets how often the RestrictionManager will poll local agent for
+// the baggage restrictions.
+func (options) RefreshInterval(refreshInterval time.Duration) Option {
+	return func(o *options) {
+		o.refreshInterval = refreshInterval
+	}
+}
+
+func applyOptions(o ...Option) options {
+	opts := options{}
+	for _, option := range o {
+		option(&opts)
+	}
+	if opts.metrics == nil {
+		opts.metrics = jaeger.NewNullMetrics()
+	}
+	if opts.logger == nil {
+		opts.logger = jaeger.NullLogger
+	}
+	if opts.hostPort == "" {
+		opts.hostPort = defaultHostPort
+	}
+	if opts.refreshInterval == 0 {
+		opts.refreshInterval = defaultRefreshInterval
+	}
+	return opts
+}

vendor/github.com/uber/jaeger-client-go/internal/baggage/remote/restriction_manager.go

@@ -0,0 +1,157 @@
+// Copyright (c) 2017 Uber Technologies, Inc.
+//
+// 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 remote
+
+import (
+	"fmt"
+	"net/url"
+	"sync"
+	"time"
+
+	"github.com/uber/jaeger-client-go/internal/baggage"
+	thrift "github.com/uber/jaeger-client-go/thrift-gen/baggage"
+	"github.com/uber/jaeger-client-go/utils"
+)
+
+type httpBaggageRestrictionManagerProxy struct {
+	url string
+}
+
+func newHTTPBaggageRestrictionManagerProxy(hostPort, serviceName string) *httpBaggageRestrictionManagerProxy {
+	v := url.Values{}
+	v.Set("service", serviceName)
+	return &httpBaggageRestrictionManagerProxy{
+		url: fmt.Sprintf("http://%s/baggageRestrictions?%s", hostPort, v.Encode()),
+	}
+}
+
+func (s *httpBaggageRestrictionManagerProxy) GetBaggageRestrictions(serviceName string) ([]*thrift.BaggageRestriction, error) {
+	var out []*thrift.BaggageRestriction
+	if err := utils.GetJSON(s.url, &out); err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+// RestrictionManager manages baggage restrictions by retrieving baggage restrictions from agent
+type RestrictionManager struct {
+	options
+
+	mux                sync.RWMutex
+	serviceName        string
+	restrictions       map[string]*baggage.Restriction
+	thriftProxy        thrift.BaggageRestrictionManager
+	pollStopped        sync.WaitGroup
+	stopPoll           chan struct{}
+	invalidRestriction *baggage.Restriction
+	validRestriction   *baggage.Restriction
+
+	// Determines if the manager has successfully retrieved baggage restrictions from agent
+	initialized bool
+}
+
+// NewRestrictionManager returns a BaggageRestrictionManager that polls the agent for the latest
+// baggage restrictions.
+func NewRestrictionManager(serviceName string, options ...Option) *RestrictionManager {
+	// TODO there is a developing use case where a single tracer can generate traces on behalf of many services.
+	// restrictionsMap will need to exist per service
+	opts := applyOptions(options...)
+	m := &RestrictionManager{
+		serviceName:        serviceName,
+		options:            opts,
+		restrictions:       make(map[string]*baggage.Restriction),
+		thriftProxy:        newHTTPBaggageRestrictionManagerProxy(opts.hostPort, serviceName),
+		stopPoll:           make(chan struct{}),
+		invalidRestriction: baggage.NewRestriction(false, 0),
+		validRestriction:   baggage.NewRestriction(true, defaultMaxValueLength),
+	}
+	m.pollStopped.Add(1)
+	go m.pollManager()
+	return m
+}
+
+// isReady returns true if the manager has retrieved baggage restrictions from the remote source.
+func (m *RestrictionManager) isReady() bool {
+	m.mux.RLock()
+	defer m.mux.RUnlock()
+	return m.initialized
+}
+
+// GetRestriction implements RestrictionManager#GetRestriction.
+func (m *RestrictionManager) GetRestriction(service, key string) *baggage.Restriction {
+	m.mux.RLock()
+	defer m.mux.RUnlock()
+	if !m.initialized {
+		if m.denyBaggageOnInitializationFailure {
+			return m.invalidRestriction
+		}
+		return m.validRestriction
+	}
+	if restriction, ok := m.restrictions[key]; ok {
+		return restriction
+	}
+	return m.invalidRestriction
+}
+
+// Close stops remote polling and closes the RemoteRestrictionManager.
+func (m *RestrictionManager) Close() error {
+	close(m.stopPoll)
+	m.pollStopped.Wait()
+	return nil
+}
+
+func (m *RestrictionManager) pollManager() {
+	defer m.pollStopped.Done()
+	// attempt to initialize baggage restrictions
+	if err := m.updateRestrictions(); err != nil {
+		m.logger.Error(fmt.Sprintf("Failed to initialize baggage restrictions: %s", err.Error()))
+	}
+	ticker := time.NewTicker(m.refreshInterval)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ticker.C:
+			if err := m.updateRestrictions(); err != nil {
+				m.logger.Error(fmt.Sprintf("Failed to update baggage restrictions: %s", err.Error()))
+			}
+		case <-m.stopPoll:
+			return
+		}
+	}
+}
+
+func (m *RestrictionManager) updateRestrictions() error {
+	restrictions, err := m.thriftProxy.GetBaggageRestrictions(m.serviceName)
+	if err != nil {
+		m.metrics.BaggageRestrictionsUpdateFailure.Inc(1)
+		return err
+	}
+	newRestrictions := m.parseRestrictions(restrictions)
+	m.metrics.BaggageRestrictionsUpdateSuccess.Inc(1)
+	m.mux.Lock()
+	defer m.mux.Unlock()
+	m.initialized = true
+	m.restrictions = newRestrictions
+	return nil
+}
+
+func (m *RestrictionManager) parseRestrictions(restrictions []*thrift.BaggageRestriction) map[string]*baggage.Restriction {
+	setters := make(map[string]*baggage.Restriction, len(restrictions))
+	for _, restriction := range restrictions {
+		setters[restriction.BaggageKey] = baggage.NewRestriction(true, int(restriction.MaxValueLength))
+	}
+	return setters
+}

vendor/github.com/uber/jaeger-client-go/internal/baggage/restriction_manager.go

@@ -0,0 +1,71 @@
+// Copyright (c) 2017 Uber Technologies, Inc.
+//
+// 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 baggage
+
+const (
+	defaultMaxValueLength = 2048
+)
+
+// Restriction determines whether a baggage key is allowed and contains any restrictions on the baggage value.
+type Restriction struct {
+	keyAllowed     bool
+	maxValueLength int
+}
+
+// NewRestriction returns a new Restriction.
+func NewRestriction(keyAllowed bool, maxValueLength int) *Restriction {
+	return &Restriction{
+		keyAllowed:     keyAllowed,
+		maxValueLength: maxValueLength,
+	}
+}
+
+// KeyAllowed returns whether the baggage key for this restriction is allowed.
+func (r *Restriction) KeyAllowed() bool {
+	return r.keyAllowed
+}
+
+// MaxValueLength returns the max length for the baggage value.
+func (r *Restriction) MaxValueLength() int {
+	return r.maxValueLength
+}
+
+// RestrictionManager keeps track of valid baggage keys and their restrictions. The manager
+// will return a Restriction for a specific baggage key which will determine whether the baggage
+// key is allowed for the current service and any other applicable restrictions on the baggage
+// value.
+type RestrictionManager interface {
+	GetRestriction(service, key string) *Restriction
+}
+
+// DefaultRestrictionManager allows any baggage key.
+type DefaultRestrictionManager struct {
+	defaultRestriction *Restriction
+}
+
+// NewDefaultRestrictionManager returns a DefaultRestrictionManager.
+func NewDefaultRestrictionManager(maxValueLength int) *DefaultRestrictionManager {
+	if maxValueLength == 0 {
+		maxValueLength = defaultMaxValueLength
+	}
+	return &DefaultRestrictionManager{
+		defaultRestriction: &Restriction{keyAllowed: true, maxValueLength: maxValueLength},
+	}
+}
+
+// GetRestriction implements RestrictionManager#GetRestriction.
+func (m *DefaultRestrictionManager) GetRestriction(service, key string) *Restriction {
+	return m.defaultRestriction
+}

vendor/github.com/uber/jaeger-client-go/internal/spanlog/json.go

@@ -1,22 +1,16 @@
-// Copyright (c) 2016 Uber Technologies, Inc.
-
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
+// Copyright (c) 2017 Uber Technologies, Inc.
 //
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
+// 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
 //
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
+// 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 spanlog
 

vendor/github.com/uber/jaeger-client-go/internal/throttler/remote/options.go

@@ -0,0 +1,99 @@
+// Copyright (c) 2018 The Jaeger 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 remote
+
+import (
+	"time"
+
+	"github.com/uber/jaeger-client-go"
+)
+
+const (
+	defaultHostPort        = "localhost:5778"
+	defaultRefreshInterval = time.Second * 5
+)
+
+// Option is a function that sets some option on the Throttler
+type Option func(options *options)
+
+// Options is a factory for all available options
+var Options options
+
+type options struct {
+	metrics                   *jaeger.Metrics
+	logger                    jaeger.Logger
+	hostPort                  string
+	refreshInterval           time.Duration
+	synchronousInitialization bool
+}
+
+// Metrics creates an Option that initializes Metrics on the Throttler, which is used to emit statistics.
+func (options) Metrics(m *jaeger.Metrics) Option {
+	return func(o *options) {
+		o.metrics = m
+	}
+}
+
+// Logger creates an Option that sets the logger used by the Throttler.
+func (options) Logger(logger jaeger.Logger) Option {
+	return func(o *options) {
+		o.logger = logger
+	}
+}
+
+// HostPort creates an Option that sets the hostPort of the local agent that keeps track of credits.
+func (options) HostPort(hostPort string) Option {
+	return func(o *options) {
+		o.hostPort = hostPort
+	}
+}
+
+// RefreshInterval creates an Option that sets how often the Throttler will poll local agent for
+// credits.
+func (options) RefreshInterval(refreshInterval time.Duration) Option {
+	return func(o *options) {
+		o.refreshInterval = refreshInterval
+	}
+}
+
+// SynchronousInitialization creates an Option that determines whether the throttler should synchronously
+// fetch credits from the agent when an operation is seen for the first time. This should be set to true
+// if the client will be used by a short lived service that needs to ensure that credits are fetched upfront
+// such that sampling or throttling occurs.
+func (options) SynchronousInitialization(b bool) Option {
+	return func(o *options) {
+		o.synchronousInitialization = b
+	}
+}
+
+func applyOptions(o ...Option) options {
+	opts := options{}
+	for _, option := range o {
+		option(&opts)
+	}
+	if opts.metrics == nil {
+		opts.metrics = jaeger.NewNullMetrics()
+	}
+	if opts.logger == nil {
+		opts.logger = jaeger.NullLogger
+	}
+	if opts.hostPort == "" {
+		opts.hostPort = defaultHostPort
+	}
+	if opts.refreshInterval == 0 {
+		opts.refreshInterval = defaultRefreshInterval
+	}
+	return opts
+}

vendor/github.com/uber/jaeger-client-go/internal/throttler/remote/throttler.go

@@ -0,0 +1,216 @@
+// Copyright (c) 2018 The Jaeger 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 remote
+
+import (
+	"fmt"
+	"net/url"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/pkg/errors"
+
+	"github.com/uber/jaeger-client-go"
+	"github.com/uber/jaeger-client-go/utils"
+)
+
+const (
+	// minimumCredits is the minimum amount of credits necessary to not be throttled.
+	// i.e. if currentCredits > minimumCredits, then the operation will not be throttled.
+	minimumCredits = 1.0
+)
+
+var (
+	errorUUIDNotSet = errors.New("Throttler UUID must be set")
+)
+
+type operationBalance struct {
+	Operation string  `json:"operation"`
+	Balance   float64 `json:"balance"`
+}
+
+type creditResponse struct {
+	Balances []operationBalance `json:"balances"`
+}
+
+type httpCreditManagerProxy struct {
+	hostPort string
+}
+
+func newHTTPCreditManagerProxy(hostPort string) *httpCreditManagerProxy {
+	return &httpCreditManagerProxy{
+		hostPort: hostPort,
+	}
+}
+
+// N.B. Operations list must not be empty.
+func (m *httpCreditManagerProxy) FetchCredits(uuid, serviceName string, operations []string) (*creditResponse, error) {
+	params := url.Values{}
+	params.Set("service", serviceName)
+	params.Set("uuid", uuid)
+	for _, op := range operations {
+		params.Add("operations", op)
+	}
+	var resp creditResponse
+	if err := utils.GetJSON(fmt.Sprintf("http://%s/credits?%s", m.hostPort, params.Encode()), &resp); err != nil {
+		return nil, errors.Wrap(err, "Failed to receive credits from agent")
+	}
+	return &resp, nil
+}
+
+// Throttler retrieves credits from agent and uses it to throttle operations.
+type Throttler struct {
+	options
+
+	mux           sync.RWMutex
+	service       string
+	uuid          atomic.Value
+	creditManager *httpCreditManagerProxy
+	credits       map[string]float64 // map of operation->credits
+	close         chan struct{}
+	stopped       sync.WaitGroup
+}
+
+// NewThrottler returns a Throttler that polls agent for credits and uses them to throttle
+// the service.
+func NewThrottler(service string, options ...Option) *Throttler {
+	opts := applyOptions(options...)
+	creditManager := newHTTPCreditManagerProxy(opts.hostPort)
+	t := &Throttler{
+		options:       opts,
+		creditManager: creditManager,
+		service:       service,
+		credits:       make(map[string]float64),
+		close:         make(chan struct{}),
+	}
+	t.stopped.Add(1)
+	go t.pollManager()
+	return t
+}
+
+// IsAllowed implements Throttler#IsAllowed.
+func (t *Throttler) IsAllowed(operation string) bool {
+	t.mux.Lock()
+	defer t.mux.Unlock()
+	value, ok := t.credits[operation]
+	if !ok || value == 0 {
+		if !ok {
+			// NOTE: This appears to be a no-op at first glance, but it stores
+			// the operation key in the map. Necessary for functionality of
+			// Throttler#operations method.
+			t.credits[operation] = 0
+		}
+		if !t.synchronousInitialization {
+			t.metrics.ThrottledDebugSpans.Inc(1)
+			return false
+		}
+		// If it is the first time this operation is being checked, synchronously fetch
+		// the credits.
+		credits, err := t.fetchCredits([]string{operation})
+		if err != nil {
+			// Failed to receive credits from agent, try again next time
+			t.logger.Error("Failed to fetch credits: " + err.Error())
+			return false
+		}
+		if len(credits.Balances) == 0 {
+			// This shouldn't happen but just in case
+			return false
+		}
+		for _, opBalance := range credits.Balances {
+			t.credits[opBalance.Operation] += opBalance.Balance
+		}
+	}
+	return t.isAllowed(operation)
+}
+
+// Close stops the throttler from fetching credits from remote.
+func (t *Throttler) Close() error {
+	close(t.close)
+	t.stopped.Wait()
+	return nil
+}
+
+// SetProcess implements ProcessSetter#SetProcess. It's imperative that the UUID is set before any remote
+// requests are made.
+func (t *Throttler) SetProcess(process jaeger.Process) {
+	if process.UUID != "" {
+		t.uuid.Store(process.UUID)
+	}
+}
+
+// N.B. This function must be called with the Write Lock
+func (t *Throttler) isAllowed(operation string) bool {
+	credits := t.credits[operation]
+	if credits < minimumCredits {
+		t.metrics.ThrottledDebugSpans.Inc(1)
+		return false
+	}
+	t.credits[operation] = credits - minimumCredits
+	return true
+}
+
+func (t *Throttler) pollManager() {
+	defer t.stopped.Done()
+	ticker := time.NewTicker(t.refreshInterval)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ticker.C:
+			t.refreshCredits()
+		case <-t.close:
+			return
+		}
+	}
+}
+
+func (t *Throttler) operations() []string {
+	t.mux.RLock()
+	defer t.mux.RUnlock()
+	operations := make([]string, 0, len(t.credits))
+	for op := range t.credits {
+		operations = append(operations, op)
+	}
+	return operations
+}
+
+func (t *Throttler) refreshCredits() {
+	operations := t.operations()
+	if len(operations) == 0 {
+		return
+	}
+	newCredits, err := t.fetchCredits(operations)
+	if err != nil {
+		t.metrics.ThrottlerUpdateFailure.Inc(1)
+		t.logger.Error("Failed to fetch credits: " + err.Error())
+		return
+	}
+	t.metrics.ThrottlerUpdateSuccess.Inc(1)
+
+	t.mux.Lock()
+	defer t.mux.Unlock()
+	for _, opBalance := range newCredits.Balances {
+		t.credits[opBalance.Operation] += opBalance.Balance
+	}
+}
+
+func (t *Throttler) fetchCredits(operations []string) (*creditResponse, error) {
+	uuid := t.uuid.Load()
+	uuidStr, _ := uuid.(string)
+	if uuid == nil || uuidStr == "" {
+		return nil, errorUUIDNotSet
+	}
+	return t.creditManager.FetchCredits(uuidStr, t.service, operations)
+}

vendor/github.com/uber/jaeger-client-go/internal/throttler/throttler.go

@@ -0,0 +1,32 @@
+// Copyright (c) 2018 The Jaeger 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 throttler
+
+// Throttler is used to rate limits operations. For example, given how debug spans
+// are always sampled, a throttler can be enabled per client to rate limit the amount
+// of debug spans a client can start.
+type Throttler interface {
+	// IsAllowed determines whether the operation should be allowed and not be
+	// throttled.
+	IsAllowed(operation string) bool
+}
+
+// DefaultThrottler doesn't throttle at all.
+type DefaultThrottler struct{}
+
+// IsAllowed implements Throttler#IsAllowed.
+func (t DefaultThrottler) IsAllowed(operation string) bool {
+	return true
+}