Add new setting to decode tx OP_RETURN values

README.md

@@ -122,7 +122,7 @@ Table of Contents
       - **getmasternoderewardstotal:** Returns the total number of coins earned in masternode rewards for a specific address that arrived after a specific block height *\*only applicable to masternode coins*
   - **Claim Address:** Allows anyone to set custom display names for wallet addresses that they own using the **Sign Message** feature from their local wallet. Includes *bad word* filter support.
   - **Block Info:** Displays block summary and list of transactions for a specific block height
-  - **Transaction Info:** Displays transaction summary, list of input addresses and output addresses for a specific transaction
+  - **Transaction Info:** Displays transaction summary, optional OP_RETURN value, list of input addresses and output addresses for a specific transaction
   - **Address Info:** Displays wallet address summary (balance, total sent, total received, QR code) and a list of latest transactions for a specific wallet address
 - Choose from 22 built-in themes with tweakable settings such as light and dark options to customize the look and feel of the explorer:
   - **Exor** *\*default theme made especially for eIquidus*

lib/database.js

@@ -136,6 +136,19 @@ function save_tx(txid, blockheight, cb) {
                 subloop.next();
             }, function() {
               lib.calculate_total(vout, function(total) {
+                var op_return = null;
+                // check if the op_return value should be decoded and saved
+                if (settings.transaction_page.show_op_return) {
+                  // loop through vout to find the op_return value
+                  tx.vout.forEach(function (vout_data) {
+                    // check if the op_return value exists
+                    if (vout_data.scriptPubKey != null && vout_data.scriptPubKey.asm != null && vout_data.scriptPubKey.asm.indexOf('OP_RETURN') > -1) {
+                      // decode the op_return value
+                      op_return = hex_to_ascii(vout_data.scriptPubKey.asm.replace('OP_RETURN', '').trim());
+                    }
+                  });
+                }
+
                 var newTx = new Tx({
                   txid: tx.txid,
                   vin: nvin,
@@ -144,7 +157,8 @@ function save_tx(txid, blockheight, cb) {
                   timestamp: tx.time,
                   blockhash: tx.blockhash,
                   blockindex: blockheight,
-                  tx_type: (tx_type_vout == null ? tx_type_vin : tx_type_vout)
+                  tx_type: (tx_type_vout == null ? tx_type_vin : tx_type_vout),
+                  op_return: op_return
                 });
 
                 newTx.save(function(err) {
@@ -190,6 +204,13 @@ function check_add_db_field(model_obj, field_name, default_value, cb) {
   });
 }
 
+function hex_to_ascii(hex) {
+    var str = '';
+    for (var i = 0; i < hex.length; i += 2)
+      str += String.fromCharCode(parseInt(hex.substr(i, 2), 16));
+    return str;
+}
+
 module.exports = {
   // initialize DB
   connect: function(database, cb) {
@@ -323,7 +344,10 @@ module.exports = {
         // collection has data
         // determine if tx_type field exists
         check_add_db_field(Tx, 'tx_type', null, function(exists) {
-          return cb(true);
+          // determine if op_return field exists
+          check_add_db_field(Tx, 'op_return', null, function(exists) {
+            return cb(true);
+          });
         });
       } else
         return cb(false);

lib/settings.js

@@ -354,7 +354,10 @@ exports.transaction_page = {
   // genesis_tx: Your coins genesis transaction hash is used to determine the beginning of the blockchain
   //             For many bitcoin clones you can use the following cmd to find the list of transaction hashes from the genesis block: coin-cli getblock 00014f36c648cdbc750f7dd28487a23cd9e0b0f95f5fccc5b5d01367e3f57469
   //             NOTE: If this value is not entered correctly it will not be possible for the explorer to find or navigate to the genesis block by searching for the genesis transaction hash
-  "genesis_tx": "dd1d332ad2d8d8f49195056d482ae3c96fd2d16e9d166413b27ca7f19775644c"
+  "genesis_tx": "dd1d332ad2d8d8f49195056d482ae3c96fd2d16e9d166413b27ca7f19775644c",
+  // show_op_return: Determine whether to decode and show OP_RETURN values that may have been embeddeded in a transaction
+  //                 NOTE: Enabling this option will require a full reindex of the blockchain data before previously synced transactions can display the OP_RETURN value
+  "show_op_return": false
 };
 
 // address_page: a collection of settings that pertain to the address page

models/tx.js

@@ -9,7 +9,8 @@ var TxSchema = new Schema({
   timestamp: { type: Number, default: 0, index: true },
   blockhash: { type: String, index: true },
   blockindex: {type: Number, default: 0, index: true},
-  tx_type: { type: String, default: null }
+  tx_type: { type: String, default: null },
+  op_return: { type: String, default: null }
 }, {id: false});
 
 TxSchema.index({total: 1, total: -1, blockindex: 1, blockindex: -1});

settings.json.template

@@ -438,7 +438,10 @@
     // genesis_tx: Your coins genesis transaction hash is used to determine the beginning of the blockchain
     //             For many bitcoin clones you can use the following cmd to find the list of transaction hashes from the genesis block: coin-cli getblock 00014f36c648cdbc750f7dd28487a23cd9e0b0f95f5fccc5b5d01367e3f57469
     //             NOTE: If this value is not entered correctly it will not be possible for the explorer to find or navigate to the genesis block by searching for the genesis transaction hash
-    "genesis_tx": "dd1d332ad2d8d8f49195056d482ae3c96fd2d16e9d166413b27ca7f19775644c"
+    "genesis_tx": "dd1d332ad2d8d8f49195056d482ae3c96fd2d16e9d166413b27ca7f19775644c",
+    // show_op_return: Determine whether to decode and show OP_RETURN values that may have been embeddeded in a transaction
+    //                 NOTE: Enabling this option will require a full reindex of the blockchain data before previously synced transactions can display the OP_RETURN value
+    "show_op_return": false
   },
 
   // address_page: a collection of settings that pertain to the address page

views/tx.pug

@@ -43,6 +43,8 @@ block content
           tr
             th.text-center.d-table-cell.d-md-none
             th.d-none.d-md-table-cell #{settings.locale.tx_block_hash}
+            if settings.transaction_page.show_op_return == true
+              th='OP_RETURN'
             th.text-center #{settings.locale.confirmations}
             th.text-center #{settings.locale.timestamp}
         tbody
@@ -54,6 +56,8 @@ block content
                   span.fa.fa-eye(data-toggle='tooltip', data-placement='top', title=settings.locale.view_block)
               td.d-none.d-md-table-cell
                 a.breakWord(href='/block/' + tx.blockhash) #{tx.blockhash}
+              if settings.transaction_page.show_op_return == true
+                td.breakWord #{tx.op_return}
               td.text-center #{confirms}
               td.text-center
                 span#timestampCol
@@ -65,6 +69,8 @@ block content
                     span.fa.fa-eye(data-toggle='tooltip', data-placement='top', title=settings.locale.view_block)
                 td.d-none.d-md-table-cell
                   a.breakWord(href='/block/' + tx.blockhash) #{tx.blockhash}
+                if settings.transaction_page.show_op_return == true
+                  td.breakWord #{tx.op_return}
                 td.text-center #{confirms}
                 td.text-center
                   span#timestampCol
@@ -75,6 +81,8 @@ block content
                     span.fa.fa-eye(data-toggle='tooltip', data-placement='top', title=settings.locale.view_block)              
                 td.d-none.d-md-table-cell
                   a.breakWord(href='/block/' + tx.blockhash) #{tx.blockhash}
+                if settings.transaction_page.show_op_return == true
+                  td.breakWord #{tx.op_return}
                 td.text-center #{confirms}
                 td.text-center
                   span#timestampCol