[VOL-3678] First implementation of the BBSim-sadis-server

Change-Id: I5077a8f861f4cc6af9759f31a4a415042c05eba3
diff --git a/vendor/github.com/uber/jaeger-client-go/rpcmetrics/metrics.go b/vendor/github.com/uber/jaeger-client-go/rpcmetrics/metrics.go
new file mode 100644
index 0000000..a8cec2f
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-client-go/rpcmetrics/metrics.go
@@ -0,0 +1,124 @@
+// 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 rpcmetrics
+
+import (
+	"sync"
+
+	"github.com/uber/jaeger-lib/metrics"
+)
+
+const (
+	otherEndpointsPlaceholder = "other"
+	endpointNameMetricTag     = "endpoint"
+)
+
+// Metrics is a collection of metrics for an endpoint describing
+// throughput, success, errors, and performance.
+type Metrics struct {
+	// RequestCountSuccess is a counter of the total number of successes.
+	RequestCountSuccess metrics.Counter `metric:"requests" tags:"error=false"`
+
+	// RequestCountFailures is a counter of the number of times any failure has been observed.
+	RequestCountFailures metrics.Counter `metric:"requests" tags:"error=true"`
+
+	// RequestLatencySuccess is a latency histogram of successful requests.
+	RequestLatencySuccess metrics.Timer `metric:"request_latency" tags:"error=false"`
+
+	// RequestLatencyFailures is a latency histogram of failed requests.
+	RequestLatencyFailures metrics.Timer `metric:"request_latency" tags:"error=true"`
+
+	// HTTPStatusCode2xx is a counter of the total number of requests with HTTP status code 200-299
+	HTTPStatusCode2xx metrics.Counter `metric:"http_requests" tags:"status_code=2xx"`
+
+	// HTTPStatusCode3xx is a counter of the total number of requests with HTTP status code 300-399
+	HTTPStatusCode3xx metrics.Counter `metric:"http_requests" tags:"status_code=3xx"`
+
+	// HTTPStatusCode4xx is a counter of the total number of requests with HTTP status code 400-499
+	HTTPStatusCode4xx metrics.Counter `metric:"http_requests" tags:"status_code=4xx"`
+
+	// HTTPStatusCode5xx is a counter of the total number of requests with HTTP status code 500-599
+	HTTPStatusCode5xx metrics.Counter `metric:"http_requests" tags:"status_code=5xx"`
+}
+
+func (m *Metrics) recordHTTPStatusCode(statusCode uint16) {
+	if statusCode >= 200 && statusCode < 300 {
+		m.HTTPStatusCode2xx.Inc(1)
+	} else if statusCode >= 300 && statusCode < 400 {
+		m.HTTPStatusCode3xx.Inc(1)
+	} else if statusCode >= 400 && statusCode < 500 {
+		m.HTTPStatusCode4xx.Inc(1)
+	} else if statusCode >= 500 && statusCode < 600 {
+		m.HTTPStatusCode5xx.Inc(1)
+	}
+}
+
+// MetricsByEndpoint is a registry/cache of metrics for each unique endpoint name.
+// Only maxNumberOfEndpoints Metrics are stored, all other endpoint names are mapped
+// to a generic endpoint name "other".
+type MetricsByEndpoint struct {
+	metricsFactory    metrics.Factory
+	endpoints         *normalizedEndpoints
+	metricsByEndpoint map[string]*Metrics
+	mux               sync.RWMutex
+}
+
+func newMetricsByEndpoint(
+	metricsFactory metrics.Factory,
+	normalizer NameNormalizer,
+	maxNumberOfEndpoints int,
+) *MetricsByEndpoint {
+	return &MetricsByEndpoint{
+		metricsFactory:    metricsFactory,
+		endpoints:         newNormalizedEndpoints(maxNumberOfEndpoints, normalizer),
+		metricsByEndpoint: make(map[string]*Metrics, maxNumberOfEndpoints+1), // +1 for "other"
+	}
+}
+
+func (m *MetricsByEndpoint) get(endpoint string) *Metrics {
+	safeName := m.endpoints.normalize(endpoint)
+	if safeName == "" {
+		safeName = otherEndpointsPlaceholder
+	}
+	m.mux.RLock()
+	met := m.metricsByEndpoint[safeName]
+	m.mux.RUnlock()
+	if met != nil {
+		return met
+	}
+
+	return m.getWithWriteLock(safeName)
+}
+
+// split to make easier to test
+func (m *MetricsByEndpoint) getWithWriteLock(safeName string) *Metrics {
+	m.mux.Lock()
+	defer m.mux.Unlock()
+
+	// it is possible that the name has been already registered after we released
+	// the read lock and before we grabbed the write lock, so check for that.
+	if met, ok := m.metricsByEndpoint[safeName]; ok {
+		return met
+	}
+
+	// it would be nice to create the struct before locking, since Init() is somewhat
+	// expensive, however some metrics backends (e.g. expvar) may not like duplicate metrics.
+	met := &Metrics{}
+	tags := map[string]string{endpointNameMetricTag: safeName}
+	metrics.Init(met, m.metricsFactory, tags)
+
+	m.metricsByEndpoint[safeName] = met
+	return met
+}