Fix shadowing of unused var (#83)

* dont shadow var

* run tsts

* run all tests

* run all tests

* logging for tests

carserver/station_api_impl.go

@@ -76,7 +76,7 @@ func (s *StationAPIImpl) createOrUpdateReqStatsUnlocked(ctx context.Context, cre
 	if err == datastore.ErrNotFound {
 		stats := station.ReqStats{}
 		createFn(&stats)
-		bz, err = json.Marshal(stats)
+		bz, err := json.Marshal(stats)
 		if err != nil {
 			return fmt.Errorf("failed to marshal retrieval stats to json: %w", err)
 		}

carstore/carstore_test.go

@@ -3,19 +3,20 @@ package carstore
 import (
 	"context"
 	"errors"
+	"fmt"
 	"sync"
 	"testing"
 	"time"
 
+	"golang.org/x/sync/errgroup"
+
 	"github.com/ipld/go-ipld-prime/codec/dagcbor"
 	"github.com/ipld/go-ipld-prime/multicodec"
 
 	"github.com/filecoin-project/saturn-l2/station"
 
 	cid "github.com/ipfs/go-cid"
 
-	"golang.org/x/sync/errgroup"
-
 	"github.com/filecoin-project/dagstore"
 
 	"github.com/filecoin-project/saturn-l2/logs"
@@ -47,20 +48,25 @@ func TestPersistentCache(t *testing.T) {
 	csh.assertStorageStats(t, station.StorageStats{BytesCurrentlyStored: 0})
 	// first hit -> not found
 	csh.fetchAndAssertNotFound(reqID, rootcid)
+	fmt.Println("\n data downloaded after first hit is", csh.ms.nDownloaded())
 
 	// second hit -> not found
 	csh.fetchAndAssertNotFound(reqID, rootcid)
+	fmt.Println("\n data downloaded after second hit is", csh.ms.nDownloaded())
 
 	// wait till l2 has fetched and cached it
 	csh.assertAvailable(t, ctx, rootcid)
+	fmt.Println("\n data downloaded after caching is", csh.ms.nDownloaded())
 
 	// third hit -> found
 	csh.fetchAndAssertFound(ctx, reqID, rootcid)
 	require.EqualValues(t, len(bz), csh.ms.nDownloaded())
+	fmt.Println("\n data downloaded is after third hit", csh.ms.nDownloaded())
 
 	// fourth hit -> found
 	csh.fetchAndAssertFound(ctx, reqID, rootcid)
 	require.EqualValues(t, len(bz), csh.ms.nDownloaded())
+	fmt.Println("\n data downloaded after fetching success is", csh.ms.nDownloaded())
 
 	// wait for shard to become reclaimable again
 	require.Eventually(t, func() bool {
@@ -76,14 +82,18 @@ func TestPersistentCache(t *testing.T) {
 	require.Len(t, res.Shards, 1)
 	csh.assertStorageStats(t, station.StorageStats{BytesCurrentlyStored: 0})
 
+	fmt.Println("\n data downloaded after dagstore GC is", csh.ms.nDownloaded())
+
 	// fetch car -> fails as we do not have it but will trigger a fetch again
 	csh.fetchAndAssertNotFound(reqID, rootcid)
+	fmt.Println("\n data downloaded after fetch trigger fails is", csh.ms.nDownloaded())
 
 	// fetch car -> works now as car file was downloaded in the previous fetch
 	require.Eventually(t, func() bool {
 		err = csh.cs.FetchAndWriteCAR(reqID, rootcid, func(_ bstore.Blockstore) error {
 			return nil
 		})
+		fmt.Println("\n data downloaded  after a cycle is", csh.ms.nDownloaded())
 		return err == nil
 	}, 50*time.Second, 200*time.Millisecond)
 

carstore/gateway_api.go

@@ -94,6 +94,7 @@ func (gw *GatewayReader) Read(p []byte) (int, error) {
 }
 
 func (gw *GatewayReader) Close() error {
+	fmt.Println("\n Recoding downloaded data", gw.n)
 	if err := gw.sapi.RecordDataDownloaded(gw.ctx, gw.n); err != nil {
 		log.Errorw("failed to record download stats", "err", err)
 		return err