From f235d1056d0f76e3c55697ebfab41cf7ce0eb0e5 Mon Sep 17 00:00:00 2001
From: Viacheslav <viacheslavgonkivskyi@gmail.com>
Date: Tue, 30 Jan 2024 14:22:00 +0200
Subject: [PATCH] feat(blob/trace): cover blob service with traces (#3113)

Cover Blob service with Otel traces. Partly fixes #3112
---
 blob/service.go | 50 +++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 44 insertions(+), 6 deletions(-)

diff --git a/blob/service.go b/blob/service.go
index 6a70772797..fc1d630e62 100644
--- a/blob/service.go
+++ b/blob/service.go
@@ -11,12 +11,17 @@ import (
 	"github.com/cosmos/cosmos-sdk/types"
 	auth "github.com/cosmos/cosmos-sdk/x/auth/types"
 	logging "github.com/ipfs/go-log/v2"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+	"go.opentelemetry.io/otel/trace"
 
 	"github.com/celestiaorg/celestia-app/pkg/appconsts"
 	"github.com/celestiaorg/celestia-app/pkg/shares"
 	blobtypes "github.com/celestiaorg/celestia-app/x/blob/types"
 
 	"github.com/celestiaorg/celestia-node/header"
+	"github.com/celestiaorg/celestia-node/libs/utils"
 	"github.com/celestiaorg/celestia-node/share"
 )
 
@@ -24,7 +29,8 @@ var (
 	ErrBlobNotFound = errors.New("blob: not found")
 	ErrInvalidProof = errors.New("blob: invalid proof")
 
-	log = logging.Logger("blob")
+	log    = logging.Logger("blob")
+	tracer = otel.Tracer("blob/service")
 )
 
 // GasPrice represents the amount to be paid per gas unit. Fee is set by
@@ -185,7 +191,11 @@ func (s *Service) Included(
 	namespace share.Namespace,
 	proof *Proof,
 	com Commitment,
-) (bool, error) {
+) (_ bool, err error) {
+	ctx, span := tracer.Start(ctx, "included")
+	defer func() {
+		utils.SetStatusAndEnd(span, err)
+	}()
 	// In the current implementation, LNs will have to download all shares to recompute the commitment.
 	// To achieve 1. we need to modify Proof structure and to store all subtree roots, that were
 	// involved in commitment creation and then call `merkle.HashFromByteSlices`(tendermint package).
@@ -213,24 +223,47 @@ func (s *Service) getByCommitment(
 	height uint64,
 	namespace share.Namespace,
 	commitment Commitment,
-) (*Blob, *Proof, error) {
+) (_ *Blob, _ *Proof, err error) {
 	log.Infow("requesting blob",
 		"height", height,
 		"namespace", namespace.String())
 
-	header, err := s.headerGetter(ctx, height)
+	ctx, span := tracer.Start(ctx, "get-by-commitment")
+	defer func() {
+		utils.SetStatusAndEnd(span, err)
+	}()
+	span.SetAttributes(
+		attribute.Int64("height", int64(height)),
+		attribute.String("commitment", string(commitment)),
+	)
+
+	getCtx, headerGetterSpan := tracer.Start(ctx, "header-getter")
+
+	header, err := s.headerGetter(getCtx, height)
 	if err != nil {
+		headerGetterSpan.SetStatus(codes.Error, err.Error())
 		return nil, nil, err
 	}
 
-	namespacedShares, err := s.shareGetter.GetSharesByNamespace(ctx, header, namespace)
+	headerGetterSpan.SetStatus(codes.Ok, "")
+	headerGetterSpan.AddEvent("received eds", trace.WithAttributes(
+		attribute.Int64("eds-size", int64(len(header.DAH.RowRoots)))))
+
+	getCtx, getSharesSpan := tracer.Start(ctx, "get-shares-by-namespace")
+
+	namespacedShares, err := s.shareGetter.GetSharesByNamespace(getCtx, header, namespace)
 	if err != nil {
 		if errors.Is(err, share.ErrNotFound) {
 			err = ErrBlobNotFound
 		}
+		getSharesSpan.SetStatus(codes.Error, err.Error())
 		return nil, nil, err
 	}
 
+	getSharesSpan.SetStatus(codes.Ok, "")
+	getSharesSpan.AddEvent("received shares", trace.WithAttributes(
+		attribute.Int64("eds-size", int64(len(header.DAH.RowRoots)))))
+
 	var (
 		rawShares = make([]shares.Share, 0)
 		proofs    = make(Proof, 0)
@@ -260,6 +293,7 @@ func (s *Service) getByCommitment(
 		}
 		for _, b := range blobs {
 			if b.Commitment.Equal(commitment) {
+				span.AddEvent("blob reconstructed")
 				return b, &proofs, nil
 			}
 			// Falling under this flag means that the data from the last row
@@ -296,7 +330,11 @@ func (s *Service) getBlobs(
 	ctx context.Context,
 	namespace share.Namespace,
 	header *header.ExtendedHeader,
-) ([]*Blob, error) {
+) (_ []*Blob, err error) {
+	ctx, span := tracer.Start(ctx, "get-blobs")
+	defer func() {
+		utils.SetStatusAndEnd(span, err)
+	}()
 	namespacedShares, err := s.shareGetter.GetSharesByNamespace(ctx, header, namespace)
 	if err != nil {
 		return nil, err