From 5a2daff8b418a42f834248e2acd69ec3afb0ee14 Mon Sep 17 00:00:00 2001
From: CocoaHuke <cocoatouch@outlook.com>
Date: Thu, 21 Jun 2018 16:32:09 -0700
Subject: [PATCH] Update light/odr_util.go

---
 light/odr_util.go | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/light/odr_util.go b/light/odr_util.go
index 620af63835..c7276b7818 100644
--- a/light/odr_util.go
+++ b/light/odr_util.go
@@ -230,3 +230,42 @@ func GetBloomBits(ctx context.Context, odr OdrBackend, bitIdx uint, sectionIdxLi
 		return result, nil
 	}
 }
+
+//GetTxStatus requests full nodes to retrieve the status of transaction corresponding to the hash.
+//Message of the LES/2 protocol version (LPV2)
+func GetTxStatus(ctx context.Context, odr OdrBackend, txHash common.Hash) (core.TxStatus, error) {
+
+  // Return "Included" status if query success from database
+  bHash, bIndex, _ := rawdb.ReadTxLookupEntry(odr.Database(), txHash)
+  if bHash != (common.Hash{}) {
+		return core.TxStatusIncluded, nil
+  }
+
+  // Send on-demand request message
+	r := &TxStatusRequest{TxHash: txHash}
+	if err := odr.Retrieve(ctx, r); err != nil {
+		return core.TxStatusUnknown, err
+	}
+
+  if r.TxStatus != core.TxStatusIncluded {
+		return r.TxStatus, nil
+	}
+
+	// Another on-demand request message for retrieve block body, verify block body internally
+	bHash, bIndex, _ = r.TxEntry.BlockHash, r.TxEntry.BlockIndex, r.TxEntry.Index
+  bBody, err := GetBody(ctx, odr, bHash, bIndex)
+	if err != nil {
+		return r.TxStatus, err
+	}
+
+  // Try to find matched transaction by given hash, verifying transaction by given hash whether exist
+	for _, tx := range bBody.Transactions {
+		if tx.Hash() == r.TxHash {
+				// Write into database if hash matched, link given hash to verified block hash and index
+				r.StoreResult(odr.Database())
+				break
+		}
+	}
+
+	return r.TxStatus, nil
+}