Fix #303 Live logs

app/lib/directory.js

@@ -10,10 +10,15 @@ module.exports = {
 
   INSTANCE_NAME: getDomain(opts.mdb),
   INSTANCE_HOME: getHomePath(opts.mdb, opts.home),
+  INSTANCE_HOMELOG_FILE: getLogsPath(opts.mdb, opts.home),
 
   getHome: (profile, dir) => getHomePath(profile, dir)
 };
 
+function getLogsPath(profile, dir) {
+  return path.join(getHomePath(profile, dir), 'ucoin.log');
+}
+
 function getHomePath(profile, dir) {
   return path.normalize(getUserHome(dir) + '/') + getDomain(profile);
 }

bin/daemon

@@ -3,6 +3,9 @@
 
 var directory = require('../app/lib/directory');
 var path = require('path');
+var Tail = require('always-tail');
+var fs = require('fs');
+var util = require('util');
 
 var daemon = require("daemonize2").setup({
   main: "ucoind",
@@ -20,6 +23,19 @@ switch (process.argv[2]) {
     daemon.stop();
     break;
 
+  case "logs":
+    let stats = fs.statSync(directory.INSTANCE_HOMELOG_FILE);
+    let fileSizeInBytes = stats.size;
+    let lastLines = 0.995 * fileSizeInBytes;
+    var tail = new Tail(directory.INSTANCE_HOMELOG_FILE, '\n', {
+      interval: 5,
+      start: Math.max(0, lastLines)
+    });
+    tail.on("line", function(data) {
+      console.log(data);
+    });
+    break;
+
   case "restart":
     daemon.stop(function(err) {
       err && console.error(err);

package.json

@@ -33,6 +33,7 @@
     "url": "https://github.com/ucoin-io/ucoin/issues"
   },
   "dependencies": {
+    "always-tail": "0.2.0",
     "async": "0.2.9",
     "bindings": "1.2.1",
     "co": "4.6.0",

ucoin.sh

@@ -35,7 +35,7 @@ ucoind() {
 		#  UCOIN DAEMON MANAGEMENT
 		#---------------------------------
 
-		start|stop|restart)
+		start|stop|restart|logs)
 		$NODE "$UCOIN_DIR/bin/daemon" $*
 		;;