refactor: combine tracing & metrics in observability package

cmd/gotosocial/action/server/server.go

@@ -50,9 +50,9 @@ import (
 	"github.com/superseriousbusiness/gotosocial/internal/media"
 	"github.com/superseriousbusiness/gotosocial/internal/media/ffmpeg"
 	"github.com/superseriousbusiness/gotosocial/internal/messages"
-	"github.com/superseriousbusiness/gotosocial/internal/metrics"
 	"github.com/superseriousbusiness/gotosocial/internal/middleware"
 	"github.com/superseriousbusiness/gotosocial/internal/oauth"
+	"github.com/superseriousbusiness/gotosocial/internal/observability"
 	"github.com/superseriousbusiness/gotosocial/internal/oidc"
 	"github.com/superseriousbusiness/gotosocial/internal/processing"
 	tlprocessor "github.com/superseriousbusiness/gotosocial/internal/processing/timeline"
@@ -61,7 +61,6 @@ import (
 	gtsstorage "github.com/superseriousbusiness/gotosocial/internal/storage"
 	"github.com/superseriousbusiness/gotosocial/internal/subscriptions"
 	"github.com/superseriousbusiness/gotosocial/internal/timeline"
-	"github.com/superseriousbusiness/gotosocial/internal/tracing"
 	"github.com/superseriousbusiness/gotosocial/internal/transport"
 	"github.com/superseriousbusiness/gotosocial/internal/typeutils"
 	"github.com/superseriousbusiness/gotosocial/internal/web"
@@ -196,7 +195,7 @@ var Start action.GTSAction = func(ctx context.Context) error {
 	}
 
 	// Initialize tracing (noop if not enabled).
-	if err := tracing.Initialize(); err != nil {
+	if err := observability.InitializeTracing(); err != nil {
 		return fmt.Errorf("error initializing tracing: %w", err)
 	}
 
@@ -393,7 +392,7 @@ var Start action.GTSAction = func(ctx context.Context) error {
 	}
 
 	// Initialize metrics.
-	if err := metrics.Initialize(state.DB); err != nil {
+	if err := observability.InitializeMetrics(state.DB); err != nil {
 		return fmt.Errorf("error initializing metrics: %w", err)
 	}
 
@@ -426,12 +425,12 @@ var Start action.GTSAction = func(ctx context.Context) error {
 
 	// Add tracing middleware if enabled.
 	if config.GetTracingEnabled() {
-		middlewares = append(middlewares, tracing.InstrumentGin())
+		middlewares = append(middlewares, observability.TracingMiddleware())
 	}
 
 	// Add metrics middleware if enabled.
 	if config.GetMetricsEnabled() {
-		middlewares = append(middlewares, metrics.InstrumentGin())
+		middlewares = append(middlewares, observability.MetricsMiddleware())
 	}
 
 	middlewares = append(middlewares, []gin.HandlerFunc{

cmd/gotosocial/action/testrig/testrig.go

@@ -38,8 +38,8 @@ import (
 	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
 	"github.com/superseriousbusiness/gotosocial/internal/language"
 	"github.com/superseriousbusiness/gotosocial/internal/log"
-	"github.com/superseriousbusiness/gotosocial/internal/metrics"
 	"github.com/superseriousbusiness/gotosocial/internal/middleware"
+	"github.com/superseriousbusiness/gotosocial/internal/observability"
 	"github.com/superseriousbusiness/gotosocial/internal/oidc"
 	tlprocessor "github.com/superseriousbusiness/gotosocial/internal/processing/timeline"
 	"github.com/superseriousbusiness/gotosocial/internal/router"
@@ -47,7 +47,6 @@ import (
 	"github.com/superseriousbusiness/gotosocial/internal/storage"
 	"github.com/superseriousbusiness/gotosocial/internal/subscriptions"
 	"github.com/superseriousbusiness/gotosocial/internal/timeline"
-	"github.com/superseriousbusiness/gotosocial/internal/tracing"
 	"github.com/superseriousbusiness/gotosocial/internal/typeutils"
 	"github.com/superseriousbusiness/gotosocial/internal/web"
 	"github.com/superseriousbusiness/gotosocial/testrig"
@@ -127,7 +126,7 @@ var Start action.GTSAction = func(ctx context.Context) error {
 	}
 	config.SetInstanceLanguages(parsedLangs)
 
-	if err := tracing.Initialize(); err != nil {
+	if err := observability.InitializeTracing(); err != nil {
 		return fmt.Errorf("error initializing tracing: %w", err)
 	}
 
@@ -195,7 +194,7 @@ var Start action.GTSAction = func(ctx context.Context) error {
 	defer testrig.StopWorkers(state)
 
 	// Initialize metrics.
-	if err := metrics.Initialize(state.DB); err != nil {
+	if err := observability.InitializeMetrics(state.DB); err != nil {
 		return fmt.Errorf("error initializing metrics: %w", err)
 	}
 
@@ -213,11 +212,11 @@ var Start action.GTSAction = func(ctx context.Context) error {
 		middleware.AddRequestID(config.GetRequestIDHeader()), // requestID middleware must run before tracing
 	}
 	if config.GetTracingEnabled() {
-		middlewares = append(middlewares, tracing.InstrumentGin())
+		middlewares = append(middlewares, observability.TracingMiddleware())
 	}
 
 	if config.GetMetricsEnabled() {
-		middlewares = append(middlewares, metrics.InstrumentGin())
+		middlewares = append(middlewares, observability.MetricsMiddleware())
 	}
 
 	middlewares = append(middlewares, []gin.HandlerFunc{

internal/api/metrics/metrics.go

@@ -15,7 +15,7 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-//go:build !nometrics
+//go:build !nootel
 
 package metrics
 

internal/api/metrics/no_metrics.go

@@ -15,7 +15,7 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-//go:build nometrics
+//go:build nootel
 
 package metrics
 

internal/db/bundb/bundb.go

@@ -41,9 +41,8 @@ import (
 	"github.com/superseriousbusiness/gotosocial/internal/db/bundb/migrations"
 	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
 	"github.com/superseriousbusiness/gotosocial/internal/log"
-	"github.com/superseriousbusiness/gotosocial/internal/metrics"
+	"github.com/superseriousbusiness/gotosocial/internal/observability"
 	"github.com/superseriousbusiness/gotosocial/internal/state"
-	"github.com/superseriousbusiness/gotosocial/internal/tracing"
 	"github.com/uptrace/bun"
 	"github.com/uptrace/bun/dialect"
 	"github.com/uptrace/bun/dialect/pgdialect"
@@ -324,11 +323,10 @@ func bunDB(sqldb *sql.DB, dialect func() schema.Dialect) *bun.DB {
 
 	// Add our SQL connection hooks.
 	db.AddQueryHook(queryHook{})
-	if config.GetTracingEnabled() {
+	metricsEnabled := config.GetMetricsEnabled()
-		db.AddQueryHook(tracing.InstrumentBun())
+	tracingEnabled := config.GetTracingEnabled()
-	}
+	if metricsEnabled || tracingEnabled {
-	if config.GetMetricsEnabled() {
+		db.AddQueryHook(observability.InstrumentBun(tracingEnabled, metricsEnabled))
-		db.AddQueryHook(metrics.InstrumentBun())
 	}
 
 	// table registration is needed for many-to-many, see:

internal/observability/bun.go

@@ -15,29 +15,28 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-//go:build notracing
+//go:build !nootel
 
-package tracing
+package observability
 
 import (
-	"errors"
-
-	"github.com/gin-gonic/gin"
-	"github.com/superseriousbusiness/gotosocial/internal/config"
 	"github.com/uptrace/bun"
+	"github.com/uptrace/bun/extra/bunotel"
+	metricnoop "go.opentelemetry.io/otel/metric/noop"
+	tracenoop "go.opentelemetry.io/otel/trace/noop"
 )
 
-func Initialize() error {
+func InstrumentBun(traces bool, metrics bool) bun.QueryHook {
-	if config.GetTracingEnabled() {
+	opts := []bunotel.Option{
-		return errors.New("tracing was disabled at build time")
+		bunotel.WithFormattedQueries(true),
 	}
-	return nil
+	if !traces {
-}
+		opts = append(opts, bunotel.WithTracerProvider(tracenoop.NewTracerProvider()))
-
+	}
-func InstrumentGin() gin.HandlerFunc {
+	if !metrics {
-	return func(c *gin.Context) {}
+		opts = append(opts, bunotel.WithMeterProvider(metricnoop.NewMeterProvider()))
-}
+	}
-
+	return bunotel.NewQueryHook(
-func InstrumentBun() bun.QueryHook {
+		opts...,
-	return nil
+	)
 }

internal/observability/metrics.go

@@ -15,24 +15,24 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-//go:build !nometrics
+//go:build !nootel
 
-package metrics
+package observability
 
 import (
 	"context"
 	"errors"
 
-	"github.com/gin-gonic/gin"
 	"github.com/superseriousbusiness/gotosocial/internal/config"
 	"github.com/superseriousbusiness/gotosocial/internal/db"
+
+	"github.com/gin-gonic/gin"
 	"github.com/technologize/otel-go-contrib/otelginmetrics"
-	"github.com/uptrace/bun"
-	"github.com/uptrace/bun/extra/bunotel"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/exporters/prometheus"
 	"go.opentelemetry.io/otel/metric"
 	sdk "go.opentelemetry.io/otel/sdk/metric"
+	"go.opentelemetry.io/otel/sdk/metric/exemplar"
 	"go.opentelemetry.io/otel/sdk/resource"
 	semconv "go.opentelemetry.io/otel/semconv/v1.24.0"
 )
@@ -41,7 +41,7 @@ const (
 	serviceName = "GoToSocial"
 )
 
-func Initialize(db db.DB) error {
+func InitializeMetrics(db db.DB) error {
 	if !config.GetMetricsEnabled() {
 		return nil
 	}
@@ -66,6 +66,7 @@ func Initialize(db db.DB) error {
 	}
 
 	meterProvider := sdk.NewMeterProvider(
+		sdk.WithExemplarFilter(exemplar.AlwaysOffFilter),
 		sdk.WithResource(r),
 		sdk.WithReader(prometheusExporter),
 	)
@@ -127,12 +128,6 @@ func Initialize(db db.DB) error {
 	return nil
 }
 
-func InstrumentGin() gin.HandlerFunc {
+func MetricsMiddleware() gin.HandlerFunc {
 	return otelginmetrics.Middleware(serviceName)
 }
-
-func InstrumentBun() bun.QueryHook {
-	return bunotel.NewQueryHook(
-		bunotel.WithMeterProvider(otel.GetMeterProvider()),
-	)
-}

internal/observability/no_otel.go

@@ -15,30 +15,32 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-//go:build nometrics
+//go:build nootel
 
-package metrics
+package observability
 
 import (
-	"errors"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
 
 	"github.com/gin-gonic/gin"
-	"github.com/superseriousbusiness/gotosocial/internal/config"
-	"github.com/superseriousbusiness/gotosocial/internal/db"
 	"github.com/uptrace/bun"
 )
 
-func Initialize(db db.DB) error {
+func InitializeMetrics(db db.DB) error {
-	if config.GetMetricsEnabled() {
+	return nil
-		return errors.New("metrics was disabled at build time")
+}
-	}
+func InitializeTracing() error {
 	return nil
 }
 
-func InstrumentGin() gin.HandlerFunc {
+func MetricsMiddleware() gin.HandlerFunc {
-	return func(c *gin.Context) {}
+	return nil
-}
+}
-
+
-func InstrumentBun() bun.QueryHook {
+func TracingMiddleware() gin.HandlerFunc {
+	return nil
+}
+
+func InstrumentBun(traces bool, metrics bool) bun.QueryHook {
 	return nil
 }

internal/observability/tracing.go

@@ -15,9 +15,9 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-//go:build !notracing
+//go:build !nootel
 
-package tracing
+package observability
 
 import (
 	"context"
@@ -25,8 +25,6 @@ import (
 
 	"codeberg.org/gruf/go-kv"
 	"github.com/gin-gonic/gin"
-	"github.com/uptrace/bun"
-	"github.com/uptrace/bun/extra/bunotel"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
@@ -45,10 +43,10 @@ import (
 
 const (
 	tracerKey  = "gotosocial-server-tracer"
-	tracerName = "github.com/superseriousbusiness/gotosocial/internal/tracing"
+	tracerName = "github.com/superseriousbusiness/gotosocial/internal/observability"
 )
 
-func Initialize() error {
+func InitializeTracing() error {
 	if !config.GetTracingEnabled() {
 		return nil
 	}
@@ -119,7 +117,7 @@ func Initialize() error {
 // InstrumentGin is a middleware injecting tracing information based on the
 // otelgin implementation found at
 // https://github.com/open-telemetry/opentelemetry-go-contrib/blob/main/instrumentation/github.com/gin-gonic/gin/otelgin/gintrace.go
-func InstrumentGin() gin.HandlerFunc {
+func TracingMiddleware() gin.HandlerFunc {
 	provider := otel.GetTracerProvider()
 	tracer := provider.Tracer(
 		tracerName,
@@ -182,9 +180,3 @@ func InjectRequestID() gin.HandlerFunc {
 		}
 	}
 }
-
-func InstrumentBun() bun.QueryHook {
-	return bunotel.NewQueryHook(
-		bunotel.WithFormattedQueries(true),
-	)
-}

scripts/build.sh

@@ -17,8 +17,7 @@ GO_GCFLAGS=${GO_GCFLAGS-}
 # Available Go build tags, with explanation, followed by benefits of enabling it:
 # - kvformat:       enables prettier output of log fields                          (slightly better performance)
 # - timetzdata:     embed timezone database inside binary                          (allow setting local time inside Docker containers, at cost of 450KB)
-# - notracing:      disables compiling-in otel tracing support                     (reduced binary size, better performance)
+# - nootel:         disables compiling-in otel support                             (reduced binary size)
-# - nometrics:      disables compiling-in otel metrics support                     (reduced binary size, better performance)
 # - noerrcaller:    disables caller function prefix in errors                      (slightly better performance, at cost of err readability)
 # - debug:          enables /debug/pprof endpoint                                  (adds debug, at performance cost)
 # - debugenv:       enables /debug/pprof endpoint if DEBUG=1 env during runtime    (adds debug, at performance cost)