From be5008ec2dab62b73692a07422d34411790febd5 Mon Sep 17 00:00:00 2001
From: rene <41963722+renaynay@users.noreply.github.com>
Date: Tue, 5 Dec 2023 18:57:14 +0100
Subject: [PATCH] feat(nodebuilder/prune): Enable sampling window for light
 nodes

---
 das/daser.go                |  2 ++
 das/daser_test.go           | 37 +++++++++++++++++++++++++++++++++++++
 nodebuilder/prune/module.go |  2 +-
 pruner/light/window.go      |  2 ++
 4 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/das/daser.go b/das/daser.go
index 40eee3d316..7d569f7e0b 100644
--- a/das/daser.go
+++ b/das/daser.go
@@ -151,6 +151,8 @@ func (d *DASer) sample(ctx context.Context, h *header.ExtendedHeader) error {
 	// short-circuit if pruning is enabled and the header is outside the
 	// availability window
 	if !d.isWithinSamplingWindow(h) {
+		log.Debugw("skipping header outside sampling window", "height", h.Height(),
+			"time", h.Time())
 		return nil
 	}
 
diff --git a/das/daser_test.go b/das/daser_test.go
index fd1eb39f7d..9eec6392cc 100644
--- a/das/daser_test.go
+++ b/das/daser_test.go
@@ -2,6 +2,7 @@ package das
 
 import (
 	"context"
+	"strconv"
 	"testing"
 	"time"
 
@@ -244,6 +245,42 @@ func TestDASerSampleTimeout(t *testing.T) {
 	}
 }
 
+// TestDASer_SamplingWindow tests the sampling window determination
+// for headers.
+func TestDASer_SamplingWindow(t *testing.T) {
+	ds := ds_sync.MutexWrap(datastore.NewMapDatastore())
+	sub := new(headertest.Subscriber)
+	fserv := &fraudtest.DummyService[*header.ExtendedHeader]{}
+	getter := getterStub{}
+	avail := mocks.NewMockAvailability(gomock.NewController(t))
+
+	// create and start DASer
+	daser, err := NewDASer(avail, sub, getter, ds, fserv, newBroadcastMock(1),
+		WithSamplingWindow(time.Second))
+	require.NoError(t, err)
+
+	var tests = []struct {
+		timestamp    time.Time
+		withinWindow bool
+	}{
+		{timestamp: time.Now().Add(-(time.Second * 5)), withinWindow: false},
+		{timestamp: time.Now().Add(-(time.Millisecond * 800)), withinWindow: true},
+		{timestamp: time.Now().Add(-(time.Hour)), withinWindow: false},
+		{timestamp: time.Now().Add(-(time.Hour * 24 * 30)), withinWindow: false},
+		{timestamp: time.Now(), withinWindow: true},
+	}
+
+	for i, tt := range tests {
+		t.Run(strconv.Itoa(i), func(t *testing.T) {
+			eh := headertest.RandExtendedHeader(t)
+			eh.RawHeader.Time = tt.timestamp
+
+			assert.Equal(t, tt.withinWindow, daser.isWithinSamplingWindow(eh))
+		})
+	}
+
+}
+
 // createDASerSubcomponents takes numGetter (number of headers
 // to store in mockGetter) and numSub (number of headers to store
 // in the mock header.Subscriber), returning a newly instantiated
diff --git a/nodebuilder/prune/module.go b/nodebuilder/prune/module.go
index 330ef21cdc..2141b74bf1 100644
--- a/nodebuilder/prune/module.go
+++ b/nodebuilder/prune/module.go
@@ -39,7 +39,7 @@ func ConstructModule(tp node.Type) fx.Option {
 			fx.Provide(func() pruner.Pruner {
 				return light.NewPruner()
 			}),
-			fx.Supply(archival.Window), // TODO @renaynay: turn this into light.Window in following PR
+			fx.Supply(light.Window),
 		)
 	default:
 		panic("unknown node type")
diff --git a/pruner/light/window.go b/pruner/light/window.go
index 53bfe4a163..dc1a9e4444 100644
--- a/pruner/light/window.go
+++ b/pruner/light/window.go
@@ -6,4 +6,6 @@ import (
 	"github.com/celestiaorg/celestia-node/pruner"
 )
 
+// Window is the availability window for light nodes in the Celestia
+// network (30 days).
 const Window = pruner.AvailabilityWindow(time.Second * 86400 * 30)