From 9d7f19b9507d1790e9cf241d3b2a57b937c12d3a Mon Sep 17 00:00:00 2001
From: whyrusleeping <why@ipfs.io>
Date: Fri, 20 Mar 2020 21:23:29 -0700
Subject: [PATCH] some cleanup

---
 chain/blocksync/graphsync_client.go | 80 ++++++++---------------------
 1 file changed, 20 insertions(+), 60 deletions(-)

diff --git a/chain/blocksync/graphsync_client.go b/chain/blocksync/graphsync_client.go
index 6fadb44b2..e5ad2134e 100644
--- a/chain/blocksync/graphsync_client.go
+++ b/chain/blocksync/graphsync_client.go
@@ -19,8 +19,6 @@ import (
 )
 
 const (
-	// could be anything? <100 though I think is the base limit
-	recursionDepth = 50
 
 	// AMT selector recursion. An AMT has arity of 8 so this gives allows
 	// us to retrieve trees with 8^10 (1,073,741,824) elements.
@@ -46,21 +44,11 @@ const (
 	maxRequestLength = 50
 )
 
-var blockHeadersSelector, fullSelector ipld.Node
-
 var amtSelector selectorbuilder.SelectorSpec
 
 func init() {
 	// builer for selectors
 	ssb := selectorbuilder.NewSelectorSpecBuilder(ipldfree.NodeBuilder())
-	// blockHeaders only selector
-	blockHeadersSelector = ssb.ExploreRecursive(ipldselector.RecursionLimitDepth(recursionDepth), ssb.ExploreIndex(blockIndexParentsField,
-		ssb.ExploreUnion(
-			ssb.ExploreAll(
-				ssb.Matcher(),
-			),
-			ssb.ExploreIndex(0, ssb.ExploreRecursiveEdge()),
-		))).Node()
 	// amt selector -- needed to selector through a messages AMT
 	amtSelector = ssb.ExploreIndex(amtHeadNodeFieldIndex,
 		ssb.ExploreRecursive(ipldselector.RecursionLimitDepth(int(amtRecursionDepth)),
@@ -69,16 +57,6 @@ func init() {
 					ssb.ExploreAll(ssb.ExploreRecursiveEdge())),
 				ssb.ExploreIndex(amtNodeValuesFieldIndex,
 					ssb.ExploreAll(ssb.Matcher())))))
-	// messages too selector
-	fullSelector = ssb.ExploreRecursive(ipldselector.RecursionLimitDepth(recursionDepth),
-		ssb.ExploreIndex(blockIndexParentsField,
-			ssb.ExploreUnion(
-				ssb.ExploreAll(
-					ssb.ExploreIndex(blockIndexMessagesField,
-						ssb.ExploreRange(0, 2, amtSelector),
-					)),
-				ssb.ExploreIndex(0, ssb.ExploreRecursiveEdge()),
-			))).Node()
 }
 
 func selectorForRequest(req *BlockSyncRequest) ipld.Node {
@@ -104,7 +82,6 @@ func selectorForRequest(req *BlockSyncRequest) ipld.Node {
 			),
 			ssb.ExploreIndex(0, ssb.ExploreRecursiveEdge()),
 		))).Node()
-
 }
 
 func firstTipsetSelector(req *BlockSyncRequest) ipld.Node {
@@ -144,43 +121,26 @@ func (bs *BlockSync) fetchBlocksGraphSync(ctx context.Context, p peer.ID, req *B
 		}
 	}
 
-	var totalDepth uint64 = 0
-	var nextReq BlockSyncRequest = *req
-	var wholeChain []*BSTipSet
-	var reachedGenesis bool
-	for totalDepth < req.RequestLength && !reachedGenesis {
-		if nextReq.RequestLength > maxRequestLength {
-			nextReq.RequestLength = maxRequestLength
-		}
-
-		sel := selectorForRequest(&nextReq)
-
-		// execute the selector forreal
-		if err := bs.executeGsyncSelector(ctx, p, req.Start[0], sel); err != nil {
-			return nil, err
-		}
-
-		// Now pull the data we fetched out of the chainstore (where it should now be persisted)
-		tempcs := store.NewChainStore(bs.bserv.Blockstore(), datastore.NewMapDatastore(), nil)
-
-		opts := ParseBSOptions(req.Options)
-		tsk := types.NewTipSetKey(req.Start...)
-		chain, err := collectChainSegment(tempcs, tsk, req.RequestLength, opts)
-		if err != nil {
-			return nil, xerrors.Errorf("failed to load chain data from chainstore after successful graphsync response (start = %v): %w", req.Start, err)
-		}
-		wholeChain = append(wholeChain, chain...)
-		totalDepth += nextReq.RequestLength
-		nextCids := make([]cid.Cid, 0, len(chain[len(chain)-1].Blocks))
-		for _, blk := range chain[len(chain)-1].Blocks {
-			if blk.Height == 0 || blk.Parents == nil {
-				reachedGenesis = true
-			}
-			nextCids = append(nextCids, blk.Cid())
-		}
-		nextReq.Start = nextCids
-		nextReq.RequestLength = req.RequestLength - totalDepth
+	if req.RequestLength > maxRequestLength {
+		req.RequestLength = maxRequestLength
 	}
 
-	return &BlockSyncResponse{Chain: wholeChain}, nil
+	sel := selectorForRequest(req)
+
+	// execute the selector forreal
+	if err := bs.executeGsyncSelector(ctx, p, req.Start[0], sel); err != nil {
+		return nil, err
+	}
+
+	// Now pull the data we fetched out of the chainstore (where it should now be persisted)
+	tempcs := store.NewChainStore(bs.bserv.Blockstore(), datastore.NewMapDatastore(), nil)
+
+	opts := ParseBSOptions(req.Options)
+	tsk := types.NewTipSetKey(req.Start...)
+	chain, err := collectChainSegment(tempcs, tsk, req.RequestLength, opts)
+	if err != nil {
+		return nil, xerrors.Errorf("failed to load chain data from chainstore after successful graphsync response (start = %v): %w", req.Start, err)
+	}
+
+	return &BlockSyncResponse{Chain: chain}, nil
 }