[#406] cli: Add --trace flag

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>

cmd/frostfs-cli/internal/common/tracing.go

@@ -0,0 +1,64 @@
+package common
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"strings"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-node/cmd/frostfs-cli/internal/commonflags"
+	commonCmd "git.frostfs.info/TrueCloudLab/frostfs-node/cmd/internal/common"
+	"git.frostfs.info/TrueCloudLab/frostfs-node/misc"
+	"git.frostfs.info/TrueCloudLab/frostfs-observability/tracing"
+	"github.com/spf13/cobra"
+	"go.opentelemetry.io/otel/trace"
+)
+
+type spanKey struct{}
+
+// StopClientCommandSpan stops tracing span for the command and prints trace ID on the standard output.
+func StopClientCommandSpan(cmd *cobra.Command, _ []string) {
+	span, ok := cmd.Context().Value(spanKey{}).(trace.Span)
+	if !ok {
+		return
+	}
+
+	span.End()
+
+	// Noop provider cannot fail on flush.
+	_ = tracing.Shutdown(cmd.Context())
+
+	cmd.PrintErrf("Trace ID: %s\n", span.SpanContext().TraceID())
+}
+
+// StartClientCommandSpan starts tracing span for the command.
+func StartClientCommandSpan(cmd *cobra.Command) {
+	enableTracing, err := cmd.Flags().GetBool(commonflags.TracingFlag)
+	if err != nil || !enableTracing {
+		return
+	}
+
+	_, err = tracing.Setup(cmd.Context(), tracing.Config{
+		Enabled:  true,
+		Exporter: tracing.NoOpExporter,
+		Service:  "frostfs-cli",
+		Version:  misc.Version,
+	})
+	commonCmd.ExitOnErr(cmd, "init tracing: %w", err)
+
+	var components sort.StringSlice
+	for c := cmd; c != nil; c = c.Parent() {
+		fmt.Println(c.Name())
+		components = append(components, c.Name())
+	}
+	for i, j := 0, len(components)-1; i < j; {
+		components.Swap(i, j)
+		i++
+		j--
+	}
+
+	operation := strings.Join(components, ".")
+	ctx, span := tracing.StartSpanFromContext(cmd.Context(), operation)
+	ctx = context.WithValue(ctx, spanKey{}, span)
+	cmd.SetContext(ctx)
+}