swarm: integrate OpenTracing; propagate ctx to internal APIs (#17169)

* swarm: propagate ctx, enable opentracing

* swarm/tracing: log error when tracing is misconfigured

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
+}