cotrib: add a helper script to show miner of a bkock

contrib/showminer.sh

@@ -0,0 +1,42 @@
+#! /bin/bash
+
+read -r -d '' help << EOM
+$0 - helper script for displaying miner of a mined block.
+
+Options:
+
+    -h Display this message.
+
+    --height Specify blockheight.
+    --hash Specify blockhash.
+EOM
+
+while getopts ":h-:" optchar; do
+	case "${optchar}" in
+		-)
+			case "${OPTARG}" in
+				hash)
+					blockhash="${!OPTIND}"; OPTIND=$(( $OPTIND + 1 ))
+					;;
+				height)
+					blockheight="${!OPTIND}"; OPTIND=$(( $OPTIND + 1 ))
+					blockhash=$(lbcctl getblockhash ${blockheight})
+					;;
+				*) echo "Unknown long option --${OPTARG}" >&2; exit -2 ;;
+                        esac
+        ;;
+		h) printf "${help}\n\n"; exit 2;;
+		*) echo "Unknown option -${OPTARG}" >&2; exit -2;;
+	esac
+done
+
+
+block=$(lbcctl getblock $blockhash)
+blockheight=$(lbcctl getblock $blockhash | jq -r .height)
+
+coinbase_txid=$(echo ${block} | jq -r '.tx[0]')
+coinbase_raw=$(lbcctl getrawtransaction ${coinbase_txid} 1)
+coinbase=$(echo ${coinbase_raw} | jq '.vin[0].coinbase')
+miner=$(echo ${coinbase} | grep -o '2f.*2f' | xxd -r -p | strings)
+
+echo ${blockheight}: ${blockhash}: ${miner}