add otel module based on uptrace-go

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

otel/client.go

@@ -0,0 +1,120 @@
+package otel
+
+import (
+	"context"
+	"fmt"
+	"runtime"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	sdklog "go.opentelemetry.io/otel/sdk/log"
+	sdkmetric "go.opentelemetry.io/otel/sdk/metric"
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
+	"go.opentelemetry.io/otel/trace"
+)
+
+const dummySpanName = "__dummy__"
+
+type client struct {
+	dsn    *DSN
+	tracer trace.Tracer
+
+	tp *sdktrace.TracerProvider
+	mp *sdkmetric.MeterProvider
+	lp *sdklog.LoggerProvider
+}
+
+func newClient(dsn *DSN) *client {
+	return &client{
+		dsn:    dsn,
+		tracer: otel.Tracer("otel-go"),
+	}
+}
+
+func (c *client) Shutdown(ctx context.Context) (lastErr error) {
+	if c.tp != nil {
+		if err := c.tp.Shutdown(ctx); err != nil {
+			lastErr = err
+		}
+		c.tp = nil
+	}
+	if c.mp != nil {
+		if err := c.mp.Shutdown(ctx); err != nil {
+			lastErr = err
+		}
+		c.mp = nil
+	}
+	if c.lp != nil {
+		if err := c.lp.Shutdown(ctx); err != nil {
+			lastErr = err
+		}
+		c.lp = nil
+	}
+	return lastErr
+}
+
+func (c *client) ForceFlush(ctx context.Context) (lastErr error) {
+	if c.tp != nil {
+		if err := c.tp.ForceFlush(ctx); err != nil {
+			lastErr = err
+		}
+	}
+	if c.mp != nil {
+		if err := c.mp.ForceFlush(ctx); err != nil {
+			lastErr = err
+		}
+	}
+	if c.lp != nil {
+		if err := c.lp.ForceFlush(ctx); err != nil {
+			lastErr = err
+		}
+	}
+	return lastErr
+}
+
+// TraceURL returns the trace URL for the span.
+func (c *client) TraceURL(span trace.Span) string {
+	sctx := span.SpanContext()
+	return fmt.Sprintf("%s/traces/%s?span_id=%s",
+		c.dsn.SiteURL(), sctx.TraceID(), sctx.SpanID().String())
+}
+
+// ReportError reports an error as a span event creating a dummy span if necessary.
+func (c *client) ReportError(ctx context.Context, err error, opts ...trace.EventOption) {
+	span := trace.SpanFromContext(ctx)
+	if !span.IsRecording() {
+		_, span = c.tracer.Start(ctx, dummySpanName)
+		defer span.End()
+	}
+
+	span.RecordError(err, opts...)
+}
+
+// ReportPanic is used with defer to report panics.
+func (c *client) ReportPanic(ctx context.Context, val any) {
+	c.reportPanic(ctx, val)
+	// Force flush since we are about to exit on panic.
+	if c.tp != nil {
+		_ = c.tp.ForceFlush(ctx)
+	}
+}
+
+func (c *client) reportPanic(ctx context.Context, val interface{}) {
+	span := trace.SpanFromContext(ctx)
+	if !span.IsRecording() {
+		_, span = c.tracer.Start(ctx, dummySpanName)
+		defer span.End()
+	}
+
+	stackTrace := make([]byte, 2048)
+	n := runtime.Stack(stackTrace, false)
+
+	span.AddEvent(
+		"log",
+		trace.WithAttributes(
+			attribute.String("log.severity", "panic"),
+			attribute.String("log.message", fmt.Sprint(val)),
+			attribute.String("exception.stackstrace", string(stackTrace[:n])),
+		),
+	)
+}