multi: add GetBlockHeader to BlockChainIO

lnwallet/btcwallet/blockchain.go

@@ -149,6 +149,15 @@ func (b *BtcWallet) GetBlock(blockHash *chainhash.Hash) (*wire.MsgBlock, error)
 	return b.chain.GetBlock(blockHash)
 }
 
+// GetBlockHeader returns a block header for the block with the given hash.
+//
+// This method is a part of the lnwallet.BlockChainIO interface.
+func (b *BtcWallet) GetBlockHeader(
+	blockHash *chainhash.Hash) (*wire.BlockHeader, error) {
+
+	return b.chain.GetBlockHeader(blockHash)
+}
+
 // GetBlockHash returns the hash of the block in the best blockchain at the
 // given height.
 //

lnwallet/interface.go

@@ -562,6 +562,9 @@ type BlockChainIO interface {
 	// GetBlock returns the block in the main chain identified by the given
 	// hash.
 	GetBlock(blockHash *chainhash.Hash) (*wire.MsgBlock, error)
+
+	// GetBlockHeader returns the block header for the given block hash.
+	GetBlockHeader(blockHash *chainhash.Hash) (*wire.BlockHeader, error)
 }
 
 // MessageSigner represents an abstract object capable of signing arbitrary

lnwallet/mock.go

@@ -364,3 +364,9 @@ func (*mockChainIO) GetBlock(blockHash *chainhash.Hash) (*wire.MsgBlock,
 
 	return nil, nil
 }
+
+func (*mockChainIO) GetBlockHeader(
+	blockHash *chainhash.Hash) (*wire.BlockHeader, error) {
+
+	return nil, nil
+}