diff --git a/vendor/github.com/uber/jaeger-client-go/constants.go b/vendor/github.com/uber/jaeger-client-go/constants.go
new file mode 100644
index 0000000..1f8578f
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-client-go/constants.go
@@ -0,0 +1,106 @@
+// 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 jaeger
+
+import (
+	"fmt"
+
+	"github.com/opentracing/opentracing-go"
+)
+
+const (
+	// JaegerClientVersion is the version of the client library reported as Span tag.
+	JaegerClientVersion = "Go-2.23.1"
+
+	// JaegerClientVersionTagKey is the name of the tag used to report client version.
+	JaegerClientVersionTagKey = "jaeger.version"
+
+	// JaegerDebugHeader is the name of HTTP header or a TextMap carrier key which,
+	// if found in the carrier, forces the trace to be sampled as "debug" trace.
+	// The value of the header is recorded as the tag on the root span, so that the
+	// trace can be found in the UI using this value as a correlation ID.
+	JaegerDebugHeader = "jaeger-debug-id"
+
+	// JaegerBaggageHeader is the name of the HTTP header that is used to submit baggage.
+	// It differs from TraceBaggageHeaderPrefix in that it can be used only in cases where
+	// a root span does not exist.
+	JaegerBaggageHeader = "jaeger-baggage"
+
+	// TracerHostnameTagKey used to report host name of the process.
+	TracerHostnameTagKey = "hostname"
+
+	// TracerIPTagKey used to report ip of the process.
+	TracerIPTagKey = "ip"
+
+	// TracerUUIDTagKey used to report UUID of the client process.
+	TracerUUIDTagKey = "client-uuid"
+
+	// SamplerTypeTagKey reports which sampler was used on the root span.
+	SamplerTypeTagKey = "sampler.type"
+
+	// SamplerParamTagKey reports the parameter of the sampler, like sampling probability.
+	SamplerParamTagKey = "sampler.param"
+
+	// TraceContextHeaderName is the http header name used to propagate tracing context.
+	// This must be in lower-case to avoid mismatches when decoding incoming headers.
+	TraceContextHeaderName = "uber-trace-id"
+
+	// TracerStateHeaderName is deprecated.
+	// Deprecated: use TraceContextHeaderName
+	TracerStateHeaderName = TraceContextHeaderName
+
+	// TraceBaggageHeaderPrefix is the prefix for http headers used to propagate baggage.
+	// This must be in lower-case to avoid mismatches when decoding incoming headers.
+	TraceBaggageHeaderPrefix = "uberctx-"
+
+	// SamplerTypeConst is the type of sampler that always makes the same decision.
+	SamplerTypeConst = "const"
+
+	// SamplerTypeRemote is the type of sampler that polls Jaeger agent for sampling strategy.
+	SamplerTypeRemote = "remote"
+
+	// SamplerTypeProbabilistic is the type of sampler that samples traces
+	// with a certain fixed probability.
+	SamplerTypeProbabilistic = "probabilistic"
+
+	// SamplerTypeRateLimiting is the type of sampler that samples
+	// only up to a fixed number of traces per second.
+	SamplerTypeRateLimiting = "ratelimiting"
+
+	// SamplerTypeLowerBound is the type of sampler that samples
+	// at least a fixed number of traces per second.
+	SamplerTypeLowerBound = "lowerbound"
+
+	// DefaultUDPSpanServerHost is the default host to send the spans to, via UDP
+	DefaultUDPSpanServerHost = "localhost"
+
+	// DefaultUDPSpanServerPort is the default port to send the spans to, via UDP
+	DefaultUDPSpanServerPort = 6831
+
+	// DefaultSamplingServerPort is the default port to fetch sampling config from, via http
+	DefaultSamplingServerPort = 5778
+
+	// DefaultMaxTagValueLength is the default max length of byte array or string allowed in the tag value.
+	DefaultMaxTagValueLength = 256
+
+	// SelfRefType is a jaeger specific reference type that supports creating a span
+	// with an already defined context.
+	selfRefType opentracing.SpanReferenceType = 99
+)
+
+var (
+	// DefaultSamplingServerURL is the default url to fetch sampling config from, via http
+	DefaultSamplingServerURL = fmt.Sprintf("http://localhost:%d/sampling", DefaultSamplingServerPort)
+)