Tizen_4.0 baseHEADsubmit/trunk/20180820.043221master

Signed-off-by: hwajeong.son <hwajeong.son@samsung.com>

7 files changed, 887 insertions, 0 deletions

diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/LICENSE b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/LICENSE
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--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/LICENSE
@@ -0,0 +1,201 @@
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diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/README.md b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/README.md
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+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/README.md
@@ -0,0 +1,245 @@
+# Go gRPC Interceptors for Prometheus monitoring 
+
+[![Travis Build](https://travis-ci.org/grpc-ecosystem/go-grpc-prometheus.svg)](https://travis-ci.org/grpc-ecosystem/go-grpc-prometheus)
+[![Go Report Card](https://goreportcard.com/badge/github.com/grpc-ecosystem/go-grpc-prometheus)](http://goreportcard.com/report/grpc-ecosystem/go-grpc-prometheus)
+[![GoDoc](http://img.shields.io/badge/GoDoc-Reference-blue.svg)](https://godoc.org/github.com/grpc-ecosystem/go-grpc-prometheus)
+[![Apache 2.0 License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](LICENSE)
+
+[Prometheus](https://prometheus.io/) monitoring for your [gRPC Go](https://github.com/grpc/grpc-go) servers and clients.
+
+A sister implementation for [gRPC Java](https://github.com/grpc/grpc-java) (same metrics, same semantics) is in [grpc-ecosystem/java-grpc-prometheus](https://github.com/grpc-ecosystem/java-grpc-prometheus).
+
+## Interceptors
+
+[gRPC Go](https://github.com/grpc/grpc-go) recently acquired support for Interceptors, i.e. middleware that is executed
+by a gRPC Server before the request is passed onto the user's application logic. It is a perfect way to implement
+common patterns: auth, logging and... monitoring.
+
+To use Interceptors in chains, please see [`go-grpc-middleware`](https://github.com/mwitkow/go-grpc-middleware).
+
+## Usage
+
+There are two types of interceptors: client-side and server-side. This package provides monitoring Interceptors for both.
+
+### Server-side
+
+```go
+import "github.com/grpc-ecosystem/go-grpc-prometheus"
+...
+    // Initialize your gRPC server's interceptor.
+    myServer := grpc.NewServer(
+        grpc.StreamInterceptor(grpc_prometheus.StreamServerInterceptor),
+        grpc.UnaryInterceptor(grpc_prometheus.UnaryServerInterceptor),
+    )
+    // Register your gRPC service implementations.
+    myservice.RegisterMyServiceServer(s.server, &myServiceImpl{})
+    // After all your registrations, make sure all of the Prometheus metrics are initialized.
+    grpc_prometheus.Register(myServer)
+    // Register Prometheus metrics handler.    
+    http.Handle("/metrics", prometheus.Handler())
+...
+```
+
+### Client-side
+
+```go
+import "github.com/grpc-ecosystem/go-grpc-prometheus"
+...
+   clientConn, err = grpc.Dial(
+       address,
+		   grpc.WithUnaryInterceptor(UnaryClientInterceptor),
+		   grpc.WithStreamInterceptor(StreamClientInterceptor)
+   )
+   client = pb_testproto.NewTestServiceClient(clientConn)
+   resp, err := client.PingEmpty(s.ctx, &myservice.Request{Msg: "hello"})
+...
+```
+
+# Metrics
+
+## Labels
+
+All server-side metrics start with `grpc_server` as Prometheus subsystem name. All client-side metrics start with `grpc_client`. Both of them have mirror-concepts. Similarly all methods
+contain the same rich labels:
+  
+  * `grpc_service` - the [gRPC service](http://www.grpc.io/docs/#defining-a-service) name, which is the combination of protobuf `package` and
+    the `grpc_service` section name. E.g. for `package = mwitkow.testproto` and 
+     `service TestService` the label will be `grpc_service="mwitkow.testproto.TestService"`
+  * `grpc_method` - the name of the method called on the gRPC service. E.g.  
+    `grpc_method="Ping"`
+  * `grpc_type` - the gRPC [type of request](http://www.grpc.io/docs/guides/concepts.html#rpc-life-cycle). 
+    Differentiating between the two is important especially for latency measurements.
+
+     - `unary` is single request, single response RPC
+     - `client_stream` is a multi-request, single response RPC
+     - `server_stream` is a single request, multi-response RPC
+     - `bidi_stream` is a multi-request, multi-response RPC
+    
+
+Additionally for completed RPCs, the following labels are used:
+
+  * `grpc_code` - the human-readable [gRPC status code](https://github.com/grpc/grpc-go/blob/master/codes/codes.go).
+    The list of all statuses is to long, but here are some common ones:
+      
+      - `OK` - means the RPC was successful
+      - `IllegalArgument` - RPC contained bad values
+      - `Internal` - server-side error not disclosed to the clients
+      
+## Counters
+
+The counters and their up to date documentation is in [server_reporter.go](server_reporter.go) and [client_reporter.go](client_reporter.go) 
+the respective Prometheus handler (usually `/metrics`). 
+
+For the purpose of this documentation we will only discuss `grpc_server` metrics. The `grpc_client` ones contain mirror concepts.
+
+For simplicity, let's assume we're tracking a single server-side RPC call of [`mwitkow.testproto.TestService`](examples/testproto/test.proto),
+calling the method `PingList`. The call succeeds and returns 20 messages in the stream.
+
+First, immediately after the server receives the call it will increment the
+`grpc_server_started_total` and start the handling time clock (if histograms are enabled). 
+
+```jsoniq
+grpc_server_started_total{grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 1
+```
+
+Then the user logic gets invoked. It receives one message from the client containing the request 
+(it's a `server_stream`):
+
+```jsoniq
+grpc_server_msg_received_total{grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 1
+```
+
+The user logic may return an error, or send multiple messages back to the client. In this case, on 
+each of the 20 messages sent back, a counter will be incremented:
+
+```jsoniq
+grpc_server_msg_sent_total{grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 20
+```
+
+After the call completes, it's status (`OK` or other [gRPC status code](https://github.com/grpc/grpc-go/blob/master/codes/codes.go)) 
+and the relevant call labels increment the `grpc_server_handled_total` counter.
+
+```jsoniq
+grpc_server_handled_total{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 1
+```
+
+## Histograms
+
+[Prometheus histograms](https://prometheus.io/docs/concepts/metric_types/#histogram) are a great way
+to measure latency distributions of your RPCs. However since it is bad practice to have metrics
+of [high cardinality](https://prometheus.io/docs/practices/instrumentation/#do-not-overuse-labels))
+the latency monitoring metrics are disabled by default. To enable them please call the following
+in your server initialization code:
+
+```jsoniq
+grpc_prometheus.EnableHandlingTimeHistogram()
+```
+
+After the call completes, it's handling time will be recorded in a [Prometheus histogram](https://prometheus.io/docs/concepts/metric_types/#histogram)
+variable `grpc_server_handling_seconds`. It contains three sub-metrics:
+
+ * `grpc_server_handling_seconds_count` - the count of all completed RPCs by status and method 
+ * `grpc_server_handling_seconds_sum` - cumulative time of RPCs by status and method, useful for 
+   calculating average handling times
+ * `grpc_server_handling_seconds_bucket` - contains the counts of RPCs by status and method in respective
+   handling-time buckets. These buckets can be used by Prometheus to estimate SLAs (see [here](https://prometheus.io/docs/practices/histograms/))
+
+The counter values will look as follows:
+
+```jsoniq
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.005"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.01"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.025"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.05"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.1"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.25"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.5"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="1"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="2.5"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="5"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="10"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="+Inf"} 1
+grpc_server_handling_seconds_sum{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 0.0003866430000000001
+grpc_server_handling_seconds_count{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 1
+```
+
+
+## Useful query examples
+
+Prometheus philosophy is to provide the most detailed metrics possible to the monitoring system, and
+let the aggregations be handled there. The verbosity of above metrics make it possible to have that
+flexibility. Here's a couple of useful monitoring queries:
+
+
+### request inbound rate
+```jsoniq
+sum(rate(grpc_server_started_total{job="foo"}[1m])) by (grpc_service)
+```
+For `job="foo"` (common label to differentiate between Prometheus monitoring targets), calculate the
+rate of requests per second (1 minute window) for each gRPC `grpc_service` that the job has. Please note
+how the `grpc_method` is being omitted here: all methods of a given gRPC service will be summed together.
+
+### unary request error rate
+```jsoniq
+sum(rate(grpc_server_handled_total{job="foo",grpc_type="unary",grpc_code!="OK"}[1m])) by (grpc_service)
+```
+For `job="foo"`, calculate the per-`grpc_service` rate of `unary` (1:1) RPCs that failed, i.e. the 
+ones that didn't finish with `OK` code.
+
+### unary request error percentage
+```jsoniq
+sum(rate(grpc_server_handled_total{job="foo",grpc_type="unary",grpc_code!="OK"}[1m])) by (grpc_service)
+ / 
+sum(rate(grpc_server_started_total{job="foo",grpc_type="unary"}[1m])) by (grpc_service)
+ * 100.0
+```
+For `job="foo"`, calculate the percentage of failed requests by service. It's easy to notice that
+this is a combination of the two above examples. This is an example of a query you would like to
+[alert on](https://prometheus.io/docs/alerting/rules/) in your system for SLA violations, e.g.
+"no more than 1% requests should fail".
+
+### average response stream size
+```jsoniq
+sum(rate(grpc_server_msg_sent_total{job="foo",grpc_type="server_stream"}[10m])) by (grpc_service)
+ /
+sum(rate(grpc_server_started_total{job="foo",grpc_type="server_stream"}[10m])) by (grpc_service)
+```
+For `job="foo"` what is the `grpc_service`-wide `10m` average of messages returned for all `
+server_stream` RPCs. This allows you to track the stream sizes returned by your system, e.g. allows 
+you to track when clients started to send "wide" queries that ret
+Note the divisor is the number of started RPCs, in order to account for in-flight requests.
+
+### 99%-tile latency of unary requests
+```jsoniq
+histogram_quantile(0.99, 
+  sum(rate(grpc_server_handling_seconds_bucket{job="foo",grpc_type="unary"}[5m])) by (grpc_service,le)
+)
+```
+For `job="foo"`, returns an 99%-tile [quantile estimation](https://prometheus.io/docs/practices/histograms/#quantiles)
+of the handling time of RPCs per service. Please note the `5m` rate, this means that the quantile
+estimation will take samples in a rolling `5m` window. When combined with other quantiles
+(e.g. 50%, 90%), this query gives you tremendous insight into the responsiveness of your system 
+(e.g. impact of caching).
+
+### percentage of slow unary queries (>250ms)
+```jsoniq
+100.0 - (
+sum(rate(grpc_server_handling_seconds_bucket{job="foo",grpc_type="unary",le="0.25"}[5m])) by (grpc_service)
+ / 
+sum(rate(grpc_server_handling_seconds_count{job="foo",grpc_type="unary"}[5m])) by (grpc_service)
+) * 100.0
+```
+For `job="foo"` calculate the by-`grpc_service` fraction of slow requests that took longer than `0.25` 
+seconds. This query is relatively complex, since the Prometheus aggregations use `le` (less or equal)
+buckets, meaning that counting "fast" requests fractions is easier. However, simple maths helps.
+This is an example of a query you would like to alert on in your system for SLA violations, 
+e.g. "less than 1% of requests are slower than 250ms".
+
+
+## Status
+
+This code has been used since August 2015 as the basis for monitoring of *production* gRPC micro services  at [Improbable](https://improbable.io).
+
+## License
+
+`go-grpc-prometheus` is released under the Apache 2.0 license. See the [LICENSE](LICENSE) file for details.
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client.go
new file mode 100644
index 0000000..d9e87b2
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client.go
@@ -0,0 +1,72 @@
+// Copyright 2016 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+// gRPC Prometheus monitoring interceptors for client-side gRPC.
+
+package grpc_prometheus
+
+import (
+	"io"
+
+	"golang.org/x/net/context"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+)
+
+// UnaryClientInterceptor is a gRPC client-side interceptor that provides Prometheus monitoring for Unary RPCs.
+func UnaryClientInterceptor(ctx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
+	monitor := newClientReporter(Unary, method)
+	monitor.SentMessage()
+	err := invoker(ctx, method, req, reply, cc, opts...)
+	if err != nil {
+		monitor.ReceivedMessage()
+	}
+	monitor.Handled(grpc.Code(err))
+	return err
+}
+
+// StreamServerInterceptor is a gRPC client-side interceptor that provides Prometheus monitoring for Streaming RPCs.
+func StreamClientInterceptor(ctx context.Context, desc *grpc.StreamDesc, cc *grpc.ClientConn, method string, streamer grpc.Streamer, opts ...grpc.CallOption) (grpc.ClientStream, error) {
+	monitor := newClientReporter(clientStreamType(desc), method)
+	clientStream, err := streamer(ctx, desc, cc, method, opts...)
+	if err != nil {
+		monitor.Handled(grpc.Code(err))
+		return nil, err
+	}
+	return &monitoredClientStream{clientStream, monitor}, nil
+}
+
+func clientStreamType(desc *grpc.StreamDesc) grpcType {
+	if desc.ClientStreams && !desc.ServerStreams {
+		return ClientStream
+	} else if !desc.ClientStreams && desc.ServerStreams {
+		return ServerStream
+	}
+	return BidiStream
+}
+
+// monitoredClientStream wraps grpc.ClientStream allowing each Sent/Recv of message to increment counters.
+type monitoredClientStream struct {
+	grpc.ClientStream
+	monitor *clientReporter
+}
+
+func (s *monitoredClientStream) SendMsg(m interface{}) error {
+	err := s.ClientStream.SendMsg(m)
+	if err == nil {
+		s.monitor.SentMessage()
+	}
+	return err
+}
+
+func (s *monitoredClientStream) RecvMsg(m interface{}) error {
+	err := s.ClientStream.RecvMsg(m)
+	if err == nil {
+		s.monitor.ReceivedMessage()
+	} else if err == io.EOF {
+		s.monitor.Handled(codes.OK)
+	} else {
+		s.monitor.Handled(grpc.Code(err))
+	}
+	return err
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client_reporter.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client_reporter.go
new file mode 100644
index 0000000..16b7615
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client_reporter.go
@@ -0,0 +1,111 @@
+// Copyright 2016 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+package grpc_prometheus
+
+import (
+	"time"
+
+	"google.golang.org/grpc/codes"
+
+	prom "github.com/prometheus/client_golang/prometheus"
+)
+
+var (
+	clientStartedCounter = prom.NewCounterVec(
+		prom.CounterOpts{
+			Namespace: "grpc",
+			Subsystem: "client",
+			Name:      "started_total",
+			Help:      "Total number of RPCs started on the client.",
+		}, []string{"grpc_type", "grpc_service", "grpc_method"})
+
+	clientHandledCounter = prom.NewCounterVec(
+		prom.CounterOpts{
+			Namespace: "grpc",
+			Subsystem: "client",
+			Name:      "handled_total",
+			Help:      "Total number of RPCs completed by the client, regardless of success or failure.",
+		}, []string{"grpc_type", "grpc_service", "grpc_method", "grpc_code"})
+
+	clientStreamMsgReceived = prom.NewCounterVec(
+		prom.CounterOpts{
+			Namespace: "grpc",
+			Subsystem: "client",
+			Name:      "msg_received_total",
+			Help:      "Total number of RPC stream messages received by the client.",
+		}, []string{"grpc_type", "grpc_service", "grpc_method"})
+
+	clientStreamMsgSent = prom.NewCounterVec(
+		prom.CounterOpts{
+			Namespace: "grpc",
+			Subsystem: "client",
+			Name:      "msg_sent_total",
+			Help:      "Total number of gRPC stream messages sent by the client.",
+		}, []string{"grpc_type", "grpc_service", "grpc_method"})
+
+	clientHandledHistogramEnabled = false
+	clientHandledHistogramOpts    = prom.HistogramOpts{
+		Namespace: "grpc",
+		Subsystem: "client",
+		Name:      "handling_seconds",
+		Help:      "Histogram of response latency (seconds) of the gRPC until it is finished by the application.",
+		Buckets:   prom.DefBuckets,
+	}
+	clientHandledHistogram *prom.HistogramVec
+)
+
+func init() {
+	prom.MustRegister(clientStartedCounter)
+	prom.MustRegister(clientHandledCounter)
+	prom.MustRegister(clientStreamMsgReceived)
+	prom.MustRegister(clientStreamMsgSent)
+}
+
+// EnableClientHandlingTimeHistogram turns on recording of handling time of RPCs.
+// Histogram metrics can be very expensive for Prometheus to retain and query.
+func EnableClientHandlingTimeHistogram(opts ...HistogramOption) {
+	for _, o := range opts {
+		o(&clientHandledHistogramOpts)
+	}
+	if !clientHandledHistogramEnabled {
+		clientHandledHistogram = prom.NewHistogramVec(
+			clientHandledHistogramOpts,
+			[]string{"grpc_type", "grpc_service", "grpc_method"},
+		)
+		prom.Register(clientHandledHistogram)
+	}
+	clientHandledHistogramEnabled = true
+}
+
+type clientReporter struct {
+	rpcType     grpcType
+	serviceName string
+	methodName  string
+	startTime   time.Time
+}
+
+func newClientReporter(rpcType grpcType, fullMethod string) *clientReporter {
+	r := &clientReporter{rpcType: rpcType}
+	if clientHandledHistogramEnabled {
+		r.startTime = time.Now()
+	}
+	r.serviceName, r.methodName = splitMethodName(fullMethod)
+	clientStartedCounter.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+	return r
+}
+
+func (r *clientReporter) ReceivedMessage() {
+	clientStreamMsgReceived.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+}
+
+func (r *clientReporter) SentMessage() {
+	clientStreamMsgSent.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+}
+
+func (r *clientReporter) Handled(code codes.Code) {
+	clientHandledCounter.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName, code.String()).Inc()
+	if clientHandledHistogramEnabled {
+		clientHandledHistogram.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Observe(time.Since(r.startTime).Seconds())
+	}
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server.go
new file mode 100644
index 0000000..f85c8c2
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server.go
@@ -0,0 +1,74 @@
+// Copyright 2016 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+// gRPC Prometheus monitoring interceptors for server-side gRPC.
+
+package grpc_prometheus
+
+import (
+	"golang.org/x/net/context"
+	"google.golang.org/grpc"
+)
+
+// PreregisterServices takes a gRPC server and pre-initializes all counters to 0.
+// This allows for easier monitoring in Prometheus (no missing metrics), and should be called *after* all services have
+// been registered with the server.
+func Register(server *grpc.Server) {
+	serviceInfo := server.GetServiceInfo()
+	for serviceName, info := range serviceInfo {
+		for _, mInfo := range info.Methods {
+			preRegisterMethod(serviceName, &mInfo)
+		}
+	}
+}
+
+// UnaryServerInterceptor is a gRPC server-side interceptor that provides Prometheus monitoring for Unary RPCs.
+func UnaryServerInterceptor(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
+	monitor := newServerReporter(Unary, info.FullMethod)
+	monitor.ReceivedMessage()
+	resp, err := handler(ctx, req)
+	monitor.Handled(grpc.Code(err))
+	if err == nil {
+		monitor.SentMessage()
+	}
+	return resp, err
+}
+
+// StreamServerInterceptor is a gRPC server-side interceptor that provides Prometheus monitoring for Streaming RPCs.
+func StreamServerInterceptor(srv interface{}, ss grpc.ServerStream, info *grpc.StreamServerInfo, handler grpc.StreamHandler) error {
+	monitor := newServerReporter(streamRpcType(info), info.FullMethod)
+	err := handler(srv, &monitoredServerStream{ss, monitor})
+	monitor.Handled(grpc.Code(err))
+	return err
+}
+
+func streamRpcType(info *grpc.StreamServerInfo) grpcType {
+	if info.IsClientStream && !info.IsServerStream {
+		return ClientStream
+	} else if !info.IsClientStream && info.IsServerStream {
+		return ServerStream
+	}
+	return BidiStream
+}
+
+// monitoredStream wraps grpc.ServerStream allowing each Sent/Recv of message to increment counters.
+type monitoredServerStream struct {
+	grpc.ServerStream
+	monitor *serverReporter
+}
+
+func (s *monitoredServerStream) SendMsg(m interface{}) error {
+	err := s.ServerStream.SendMsg(m)
+	if err == nil {
+		s.monitor.SentMessage()
+	}
+	return err
+}
+
+func (s *monitoredServerStream) RecvMsg(m interface{}) error {
+	err := s.ServerStream.RecvMsg(m)
+	if err == nil {
+		s.monitor.ReceivedMessage()
+	}
+	return err
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server_reporter.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server_reporter.go
new file mode 100644
index 0000000..628a890
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server_reporter.go
@@ -0,0 +1,157 @@
+// Copyright 2016 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+package grpc_prometheus
+
+import (
+	"time"
+
+	"google.golang.org/grpc/codes"
+
+	prom "github.com/prometheus/client_golang/prometheus"
+	"google.golang.org/grpc"
+)
+
+type grpcType string
+
+const (
+	Unary        grpcType = "unary"
+	ClientStream grpcType = "client_stream"
+	ServerStream grpcType = "server_stream"
+	BidiStream   grpcType = "bidi_stream"
+)
+
+var (
+	serverStartedCounter = prom.NewCounterVec(
+		prom.CounterOpts{
+			Namespace: "grpc",
+			Subsystem: "server",
+			Name:      "started_total",
+			Help:      "Total number of RPCs started on the server.",
+		}, []string{"grpc_type", "grpc_service", "grpc_method"})
+
+	serverHandledCounter = prom.NewCounterVec(
+		prom.CounterOpts{
+			Namespace: "grpc",
+			Subsystem: "server",
+			Name:      "handled_total",
+			Help:      "Total number of RPCs completed on the server, regardless of success or failure.",
+		}, []string{"grpc_type", "grpc_service", "grpc_method", "grpc_code"})
+
+	serverStreamMsgReceived = prom.NewCounterVec(
+		prom.CounterOpts{
+			Namespace: "grpc",
+			Subsystem: "server",
+			Name:      "msg_received_total",
+			Help:      "Total number of RPC stream messages received on the server.",
+		}, []string{"grpc_type", "grpc_service", "grpc_method"})
+
+	serverStreamMsgSent = prom.NewCounterVec(
+		prom.CounterOpts{
+			Namespace: "grpc",
+			Subsystem: "server",
+			Name:      "msg_sent_total",
+			Help:      "Total number of gRPC stream messages sent by the server.",
+		}, []string{"grpc_type", "grpc_service", "grpc_method"})
+
+	serverHandledHistogramEnabled = false
+	serverHandledHistogramOpts    = prom.HistogramOpts{
+		Namespace: "grpc",
+		Subsystem: "server",
+		Name:      "handling_seconds",
+		Help:      "Histogram of response latency (seconds) of gRPC that had been application-level handled by the server.",
+		Buckets:   prom.DefBuckets,
+	}
+	serverHandledHistogram *prom.HistogramVec
+)
+
+func init() {
+	prom.MustRegister(serverStartedCounter)
+	prom.MustRegister(serverHandledCounter)
+	prom.MustRegister(serverStreamMsgReceived)
+	prom.MustRegister(serverStreamMsgSent)
+}
+
+type HistogramOption func(*prom.HistogramOpts)
+
+// WithHistogramBuckets allows you to specify custom bucket ranges for histograms if EnableHandlingTimeHistogram is on.
+func WithHistogramBuckets(buckets []float64) HistogramOption {
+	return func(o *prom.HistogramOpts) { o.Buckets = buckets }
+}
+
+// EnableHandlingTimeHistogram turns on recording of handling time of RPCs for server-side interceptors.
+// Histogram metrics can be very expensive for Prometheus to retain and query.
+func EnableHandlingTimeHistogram(opts ...HistogramOption) {
+	for _, o := range opts {
+		o(&serverHandledHistogramOpts)
+	}
+	if !serverHandledHistogramEnabled {
+		serverHandledHistogram = prom.NewHistogramVec(
+			serverHandledHistogramOpts,
+			[]string{"grpc_type", "grpc_service", "grpc_method"},
+		)
+		prom.Register(serverHandledHistogram)
+	}
+	serverHandledHistogramEnabled = true
+}
+
+type serverReporter struct {
+	rpcType     grpcType
+	serviceName string
+	methodName  string
+	startTime   time.Time
+}
+
+func newServerReporter(rpcType grpcType, fullMethod string) *serverReporter {
+	r := &serverReporter{rpcType: rpcType}
+	if serverHandledHistogramEnabled {
+		r.startTime = time.Now()
+	}
+	r.serviceName, r.methodName = splitMethodName(fullMethod)
+	serverStartedCounter.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+	return r
+}
+
+func (r *serverReporter) ReceivedMessage() {
+	serverStreamMsgReceived.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+}
+
+func (r *serverReporter) SentMessage() {
+	serverStreamMsgSent.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+}
+
+func (r *serverReporter) Handled(code codes.Code) {
+	serverHandledCounter.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName, code.String()).Inc()
+	if serverHandledHistogramEnabled {
+		serverHandledHistogram.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Observe(time.Since(r.startTime).Seconds())
+	}
+}
+
+// preRegisterMethod is invoked on Register of a Server, allowing all gRPC services labels to be pre-populated.
+func preRegisterMethod(serviceName string, mInfo *grpc.MethodInfo) {
+	methodName := mInfo.Name
+	methodType := string(typeFromMethodInfo(mInfo))
+	// These are just references (no increments), as just referencing will create the labels but not set values.
+	serverStartedCounter.GetMetricWithLabelValues(methodType, serviceName, methodName)
+	serverStreamMsgReceived.GetMetricWithLabelValues(methodType, serviceName, methodName)
+	serverStreamMsgSent.GetMetricWithLabelValues(methodType, serviceName, methodName)
+	if serverHandledHistogramEnabled {
+		serverHandledHistogram.GetMetricWithLabelValues(methodType, serviceName, methodName)
+	}
+	for _, code := range allCodes {
+		serverHandledCounter.GetMetricWithLabelValues(methodType, serviceName, methodName, code.String())
+	}
+}
+
+func typeFromMethodInfo(mInfo *grpc.MethodInfo) grpcType {
+	if mInfo.IsClientStream == false && mInfo.IsServerStream == false {
+		return Unary
+	}
+	if mInfo.IsClientStream == true && mInfo.IsServerStream == false {
+		return ClientStream
+	}
+	if mInfo.IsClientStream == false && mInfo.IsServerStream == true {
+		return ServerStream
+	}
+	return BidiStream
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/util.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/util.go
new file mode 100644
index 0000000..372460a
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/util.go
@@ -0,0 +1,27 @@
+// Copyright 2016 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+package grpc_prometheus
+
+import (
+	"strings"
+
+	"google.golang.org/grpc/codes"
+)
+
+var (
+	allCodes = []codes.Code{
+		codes.OK, codes.Canceled, codes.Unknown, codes.InvalidArgument, codes.DeadlineExceeded, codes.NotFound,
+		codes.AlreadyExists, codes.PermissionDenied, codes.Unauthenticated, codes.ResourceExhausted,
+		codes.FailedPrecondition, codes.Aborted, codes.OutOfRange, codes.Unimplemented, codes.Internal,
+		codes.Unavailable, codes.DataLoss,
+	}
+)
+
+func splitMethodName(fullMethodName string) (string, string) {
+	fullMethodName = strings.TrimPrefix(fullMethodName, "/") // remove leading slash
+	if i := strings.Index(fullMethodName, "/"); i >= 0 {
+		return fullMethodName[:i], fullMethodName[i+1:]
+	}
+	return "unknown", "unknown"
+}