feature: otel handler

Signed-off-by: Valery Piashchynski <piashchynski.valery@gmail.com>

go.mod

@@ -8,10 +8,21 @@ require (
 	github.com/roadrunner-server/api/v4 v4.7.1
 	github.com/roadrunner-server/endure/v2 v2.4.2
 	github.com/roadrunner-server/errors v1.3.0
+	go.opentelemetry.io/otel/sdk v1.17.0
 	go.uber.org/zap v1.25.0
 )
 
+replace (
+	github.com/roadrunner-server/api/v4 => ../../api
+)
+
 require (
+	github.com/go-logr/logr v1.2.4 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	go.opentelemetry.io/otel v1.17.0 // indirect
+	go.opentelemetry.io/otel/metric v1.17.0 // indirect
+	go.opentelemetry.io/otel/trace v1.17.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
+	golang.org/x/sys v0.11.0 // indirect
 	google.golang.org/protobuf v1.31.0 // indirect
 )

go.sum

@@ -2,13 +2,17 @@ github.com/benbjohnson/clock v1.3.0 h1:ip6w0uFQkncKQ979AypyG0ER7mqUSBdKLOgAle/AT
 github.com/benbjohnson/clock v1.3.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
+github.com/go-logr/logr v1.2.4 h1:g01GSCwiDw2xSZfjJ2/T9M+S6pFdcNtFYsp+Y43HYDQ=
+github.com/go-logr/logr v1.2.4/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
+github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
+github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
 github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
-github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/roadrunner-server/api/v4 v4.7.0 h1:vZ8gYWjEpJOa8slUqPJJKENS4vrFKhvI9+nQKDtSqHU=
-github.com/roadrunner-server/api/v4 v4.7.0/go.mod h1:Ut9T2j3E22cnRJtipbU8N3WVhyV040iiDfddzojlKwY=
 github.com/roadrunner-server/api/v4 v4.7.1 h1:BYU2n92mcVyanV4w3fBSSztfP8ILUh5IyndRI1UD2/8=
 github.com/roadrunner-server/api/v4 v4.7.1/go.mod h1:Ut9T2j3E22cnRJtipbU8N3WVhyV040iiDfddzojlKwY=
 github.com/roadrunner-server/endure/v2 v2.4.2 h1:aFnPc321l5HDzE2mN5wwfksJ40lgXwfU3RSqdS1LyUQ=
@@ -17,13 +21,22 @@ github.com/roadrunner-server/errors v1.3.0 h1:kLVXpXne0jMReN7pj8KIhyYyjqKjsPC5DR
 github.com/roadrunner-server/errors v1.3.0/go.mod h1:XYVuhXvxi3yQaP/zCLB6QRZ0JvQIRaBa0SKFHL4WLKg=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+go.opentelemetry.io/otel v1.17.0 h1:MW+phZ6WZ5/uk2nd93ANk/6yJ+dVrvNWUjGhnnFU5jM=
+go.opentelemetry.io/otel v1.17.0/go.mod h1:I2vmBGtFaODIVMBSTPVDlJSzBDNf93k60E6Ft0nyjo0=
+go.opentelemetry.io/otel/metric v1.17.0 h1:iG6LGVz5Gh+IuO0jmgvpTB6YVrCGngi8QGm+pMd8Pdc=
+go.opentelemetry.io/otel/metric v1.17.0/go.mod h1:h4skoxdZI17AxwITdmdZjjYJQH5nzijUUjm+wtPph5o=
+go.opentelemetry.io/otel/sdk v1.17.0 h1:FLN2X66Ke/k5Sg3V623Q7h7nt3cHXaW1FOvKKrW0IpE=
+go.opentelemetry.io/otel/sdk v1.17.0/go.mod h1:U87sE0f5vQB7hwUoW98pW5Rz4ZDuCFBZFNUBlSgmDFQ=
+go.opentelemetry.io/otel/trace v1.17.0 h1:/SWhSRHmDPOImIAetP1QAeMnZYiQXrTy4fMMYOdSKWQ=
+go.opentelemetry.io/otel/trace v1.17.0/go.mod h1:I/4vKTgFclIsXRVucpH25X0mpFSczM7aHeaz0ZBLWjY=
 go.uber.org/goleak v1.2.0 h1:xqgm/S+aQvhWFTtR0XK3Jvg7z8kGV8P4X14IzwN3Eqk=
 go.uber.org/goleak v1.2.0/go.mod h1:XJYK+MuIchqpmGmUSAzotztawfKvYLUIgg7guXrwVUo=
 go.uber.org/multierr v1.11.0 h1:blXXJkSxSSfBVBlC76pxqeO+LN3aDfLQo+309xJstO0=
 go.uber.org/multierr v1.11.0/go.mod h1:20+QtiLqy0Nd6FdQB9TLXag12DsQkrbs3htMFfDN80Y=
 go.uber.org/zap v1.25.0 h1:4Hvk6GtkucQ790dqmj7l1eEnRdKm3k3ZUrUMS2d5+5c=
 go.uber.org/zap v1.25.0/go.mod h1:JIAUzQIH94IC4fOJQm7gMmBJP5k7wQfdcnYdPoEXJYk=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
+golang.org/x/sys v0.11.0 h1:eG7RXZHdqOJ1i+0lgLgCpSXAp6M3LYlAo6osgSi0xOM=
+golang.org/x/sys v0.11.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
 google.golang.org/protobuf v1.31.0 h1:g0LDEJHgrBl9N9r17Ru3sqWhkIx2NB67okBHPwC7hs8=

plugin.go

@@ -7,6 +7,7 @@ import (
 	"github.com/roadrunner-server/api/v4/plugins/v1/kv"
 	"github.com/roadrunner-server/endure/v2/dep"
 	"github.com/roadrunner-server/errors"
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
 	"go.uber.org/zap"
 )
 
@@ -26,6 +27,11 @@ type Configurer interface {
 	Has(name string) bool
 }
 
+// Tracer represents opentelemetry tracer (OTEL plugin)
+type Tracer interface {
+	Tracer() *sdktrace.TracerProvider
+}
+
 type Logger interface {
 	NamedLogger(name string) *zap.Logger
 }
@@ -37,6 +43,8 @@ type Plugin struct {
 	constructors map[string]kv.Constructor
 	// storages contains user-defined storages, such as boltdb-north, memcached-us and so on.
 	storages map[string]kv.Storage
+	// OTEL tracer
+	tracer *sdktrace.TracerProvider
 	// KV configuration
 	cfg       Config
 	cfgPlugin Configurer
@@ -65,6 +73,12 @@ func (p *Plugin) Init(cfg Configurer, log Logger) error {
 func (p *Plugin) Serve() chan error {
 	errCh := make(chan error, 1)
 	const op = errors.Op("kv_plugin_serve")
+
+	if p.tracer == nil {
+		// NOOP tracer
+		p.tracer = sdktrace.NewTracerProvider()
+	}
+
 	// key - storage name in the config
 	// value - storage
 	// For this config we should have 3 constructors: memory, boltdb and memcached but 4 KVs: default, boltdb-south, boltdb-north and memcached
@@ -178,6 +192,9 @@ func (p *Plugin) Collects() []*dep.In {
 			kvk := pp.(kv.Constructor)
 			p.constructors[kvk.Name()] = kvk
 		}, (*kv.Constructor)(nil)),
+		dep.Fits(func(pp any) {
+			p.tracer = pp.(Tracer).Tracer()
+		}, (*Tracer)(nil)),
 	}
 }
 
@@ -187,5 +204,8 @@ func (p *Plugin) Name() string {
 
 // RPC returns associated rpc service.
 func (p *Plugin) RPC() any {
-	return &rpc{srv: p, storages: p.storages}
+	return &rpc{
+		storages: p.storages,
+		tracer:   p.tracer,
+	}
 }