Improved time formatting and conversion

Bunyan CLI was not handling timezone conversion properly when set to use
local time. This patch uses [Moment.js][] to fix those issues.

 * Timezone conversions work properly across DST conversions
 * The timezone, when shown, is correctly shown as `±hh:mm`
 * The timzeone is omitted on short output, since it isn't that short.
   Except when UTC is used, since that can be indicated by the single
   character `Z`

Fixes #245

 [Moment.js]: http://momentjs.com/

Makefile

@@ -18,7 +18,8 @@ ifeq ($(shell uname -s),Darwin)
 endif
 NODEOPT ?= $(HOME)/opt
 
-
+# Run tests in a set timezone, so local time is predictable
+export TZ=Pacific/Honolulu
 
 #---- Files
 

bin/bunyan

@@ -25,6 +25,7 @@ var child_process = require('child_process'),
     exec = child_process.exec,
     execFile = child_process.execFile;
 var assert = require('assert');
+var moment = require('moment');
 
 var nodeSpawnSupportsStdio = (
     Number(process.version.split('.')[0]) >= 0 ||
@@ -87,6 +88,16 @@ Object.keys(levelFromName).forEach(function (name) {
 TIME_UTC = 1;  // the default, bunyan's native format
 TIME_LOCAL = 2;
 
+// Timestamp formats. Timezone is added at format time
+UTC_FORMATS = {
+    long: 'YYYY-MM-DD[T]HH:mm:ss.SSS[Z]',
+    short: 'HH:mm:ss.SSS[Z]'
+};
+LOCAL_FORMATS = {
+    long: 'YYYY-MM-DD[T]HH:mm:ss.SSSZ',
+    short: 'HH:mm:ss.SSS'
+};
+
 var timezoneOffsetMs; // used for TIME_LOCAL display
 
 
@@ -752,25 +763,26 @@ function emitRecord(rec, line, opts, stylize) {
 
         delete rec.v;
 
-        var time = rec.time;
+        var time = moment(rec.time);
+        // default to UTC
+        var zoneFormats;
         switch (opts.timeFormat) {
-        case TIME_UTC:
-            break;
         case TIME_LOCAL:
-            if (!timezoneOffsetMs) {
-                timezoneOffsetMs
-                    = (new Date(time)).getTimezoneOffset() * 60 * 1000;
-            }
-            time = new Date(
-                (new Date(time)).getTime() - timezoneOffsetMs).toISOString()
+            zoneFormats = LOCAL_FORMATS;
+            break;
+        default:
+            // default to UTC
+            zoneFormats = UTC_FORMATS;
+            time.utc();
             break;
         }
-        if (short && rec.time[10] === 'T') {
-            // Presuming `time` is ISO8601 formatted, i.e. safe to drop date.
-            time = stylize(time.substr(11), 'XXX');
+        if (short) {
+            time = time.format(zoneFormats.short);
         } else {
-            time = stylize('[' + time + ']', 'XXX');
+            // Is there any way to put square brackets in a moment format?
+            time = '[' + time.format(zoneFormats.long) + ']';
         }
+        time = stylize(time, 'XXX');
         delete rec.time;
 
         var nameStr = rec.name;

package.json

@@ -32,5 +32,8 @@
 
   "scripts": {
     "test": "make test"
+  },
+  "dependencies": {
+    "moment": "^2.10.6"
   }
 }

test/cli.test.js

@@ -86,6 +86,46 @@ test('cat simple.log', function (t) {
         }
     );
 });
+test('simple.log local long', function (t) {
+    exec(_('%s -o long -L %s/corpus/simple.log', BUNYAN, __dirname),
+             function (err, stdout, stderr) {
+        t.ifError(err)
+        t.equal(stdout,
+            '[2012-02-08T12:56:52.856-10:00]  INFO: myservice/123 on example.com: '
+            + 'My message\n');
+        t.end();
+    });
+});
+test('simple.log utc long', function (t) {
+    exec(_('%s -o long %s/corpus/simple.log', BUNYAN, __dirname),
+             function (err, stdout, stderr) {
+        t.ifError(err)
+        t.equal(stdout,
+            '[2012-02-08T22:56:52.856Z]  INFO: myservice/123 on example.com: '
+            + 'My message\n');
+        t.end();
+    });
+});
+test('simple.log local short', function (t) {
+    exec(_('%s -o short -L %s/corpus/simple.log', BUNYAN, __dirname),
+             function (err, stdout, stderr) {
+        t.ifError(err)
+        t.equal(stdout,
+            '12:56:52.856  INFO myservice: '
+            + 'My message\n');
+        t.end();
+    });
+});
+test('simple.log utc short', function (t) {
+    exec(_('%s -o short %s/corpus/simple.log', BUNYAN, __dirname),
+             function (err, stdout, stderr) {
+        t.ifError(err)
+        t.equal(stdout,
+            '22:56:52.856Z  INFO myservice: '
+            + 'My message\n');
+        t.end();
+    });
+});
 test('simple.log with color', function (t) {
     exec(_('%s --color %s/corpus/simple.log', BUNYAN, __dirname),
         function (err, stdout, stderr) {