Add prometheus as metric exporter

An init method supporting prometheus for the metric exporter has been added for the
opentelemetry pkg. NSMgr or any metric collector could now export the
metrics via prometheus.
span trace and metrics can now be individually disabled by passing nil
value to the optl init function.

go.mod

@@ -25,34 +25,38 @@ require (
 	github.com/r3labs/diff v1.1.0
 	github.com/sirupsen/logrus v1.9.0
 	github.com/spiffe/go-spiffe/v2 v2.0.0
-	github.com/stretchr/testify v1.8.3
+	github.com/stretchr/testify v1.8.4
 	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.42.0
-	go.opentelemetry.io/otel v1.16.0
+	go.opentelemetry.io/otel v1.17.0
 	go.opentelemetry.io/otel/exporters/jaeger v1.16.0
-	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v0.39.0
+	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v0.40.0
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.16.0
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.16.0
+	go.opentelemetry.io/otel/exporters/prometheus v0.40.0
 	go.opentelemetry.io/otel/exporters/zipkin v1.16.0
-	go.opentelemetry.io/otel/metric v1.16.0
-	go.opentelemetry.io/otel/sdk v1.16.0
-	go.opentelemetry.io/otel/sdk/metric v0.39.0
-	go.opentelemetry.io/otel/trace v1.16.0
+	go.opentelemetry.io/otel/metric v1.17.0
+	go.opentelemetry.io/otel/sdk v1.17.0
+	go.opentelemetry.io/otel/sdk/metric v0.40.0
+	go.opentelemetry.io/otel/trace v1.17.0
 	go.uber.org/atomic v1.7.0
 	go.uber.org/goleak v1.2.1
 	golang.org/x/net v0.11.0
 	gonum.org/v1/gonum v0.6.2
-	google.golang.org/grpc v1.55.0
-	google.golang.org/protobuf v1.30.0
+	google.golang.org/grpc v1.57.0
+	google.golang.org/protobuf v1.31.0
 	gopkg.in/yaml.v2 v2.4.0
 )
 
 require (
+	cloud.google.com/go/compute/metadata v0.2.3 // indirect
 	github.com/OneOfOne/xxhash v1.2.8 // indirect
 	github.com/agnivade/levenshtein v1.1.1 // indirect
 	github.com/armon/go-metrics v0.0.0-20190430140413-ec5e00d3c878 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/bits-and-blooms/bitset v1.2.0 // indirect
 	github.com/bytecodealliance/wasmtime-go v0.40.0 // indirect
 	github.com/cenkalti/backoff/v4 v4.2.1 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/fatih/color v1.7.0 // indirect
 	github.com/go-logr/logr v1.2.4 // indirect
@@ -61,7 +65,7 @@ require (
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/google/flatbuffers v2.0.8+incompatible // indirect
 	github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 // indirect
-	github.com/grpc-ecosystem/grpc-gateway/v2 v2.11.3 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.16.0 // indirect
 	github.com/hashicorp/go-hclog v1.1.0 // indirect
 	github.com/hashicorp/go-immutable-radix v1.0.0 // indirect
 	github.com/hashicorp/go-msgpack v1.1.5 // indirect
@@ -70,6 +74,7 @@ require (
 	github.com/klauspost/compress v1.15.11 // indirect
 	github.com/mattn/go-colorable v0.1.4 // indirect
 	github.com/mattn/go-isatty v0.0.10 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
 	github.com/minio/highwayhash v1.0.2 // indirect
 	github.com/mschoch/smat v0.2.0 // indirect
 	github.com/nats-io/jwt/v2 v2.2.1-0.20220330180145-442af02fd36a // indirect
@@ -79,24 +84,28 @@ require (
 	github.com/nats-io/nuid v1.0.1 // indirect
 	github.com/openzipkin/zipkin-go v0.4.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/prometheus/procfs v0.8.0 // indirect
+	github.com/prometheus/client_golang v1.16.0 // indirect
+	github.com/prometheus/client_model v0.4.0 // indirect
+	github.com/prometheus/common v0.42.0 // indirect
+	github.com/prometheus/procfs v0.10.1 // indirect
 	github.com/rcrowley/go-metrics v0.0.0-20201227073835-cf1acfcdf475 // indirect
 	github.com/tchap/go-patricia/v2 v2.3.1 // indirect
 	github.com/xeipuuv/gojsonpointer v0.0.0-20190905194746-02993c407bfb // indirect
 	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect
 	github.com/yashtewari/glob-intersection v0.1.0 // indirect
 	github.com/zeebo/errs v1.2.2 // indirect
 	go.etcd.io/bbolt v1.3.6 // indirect
-	go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.16.0 // indirect
-	go.opentelemetry.io/otel/exporters/otlp/otlpmetric v0.39.0 // indirect
-	go.opentelemetry.io/proto/otlp v0.19.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.17.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlpmetric v0.40.0 // indirect
+	go.opentelemetry.io/proto/otlp v1.0.0 // indirect
 	golang.org/x/crypto v0.10.0 // indirect
 	golang.org/x/mod v0.8.0 // indirect
-	golang.org/x/sys v0.9.0 // indirect
+	golang.org/x/sys v0.11.0 // indirect
 	golang.org/x/text v0.10.0 // indirect
 	golang.org/x/time v0.0.0-20211116232009-f0f3c7e86c11 // indirect
 	golang.org/x/tools v0.6.0 // indirect
-	google.golang.org/genproto v0.0.0-20230306155012-7f2fa6fef1f4 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20230530153820-e85fd2cbaebc // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20230530153820-e85fd2cbaebc // indirect
 	gopkg.in/square/go-jose.v2 v2.5.1 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )