From 788ad7cefe2c82886eafd395a38876735722104d Mon Sep 17 00:00:00 2001
From: Trent Mick <trentm@gmail.com>
Date: Tue, 2 Feb 2016 23:45:31 -0800
Subject: [PATCH] fix `LOG.child(...)` to *not* override the "hostname" field
 of the parent

Fixes #291. Fixes #303.
---
 AUTHORS                      |  1 +
 CHANGES.md                   |  4 ++++
 lib/bunyan.js                |  2 +-
 test/child-behaviour.test.js | 25 +++++++++++++++++++++++++
 4 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/AUTHORS b/AUTHORS
index 87df086..b8e1ae2 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -26,3 +26,4 @@ Denis Izmaylov (https://github.com/DenisIzmaylov)
 Guillermo Grau Panea (https://github.com/guigrpa)
 Mark LeMerise (https://github.com/MarkLeMerise)
 https://github.com/sometimesalready
+Charly Koza (https://github.com/Cactusbone)
diff --git a/CHANGES.md b/CHANGES.md
index 972b4ae..8fecc2f 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -8,6 +8,10 @@ Known issues:
 
 ## 1.5.2 (not yet released)
 
+- [pull #291, issue #303] Fix `LOG.child(...)` to *not* override the "hostname"
+  field of the parent. A use case is when one manually sets "hostname" to
+  something other than `os.hostname()`. (By github.com/Cactusbone.)
+
 - [issue #325] Allow one to set `level: 0` in `createLogger` to turn on
   logging for all levels. (Adapted from #336 by github.com/sometimesalready.)
 
diff --git a/lib/bunyan.js b/lib/bunyan.js
index bda7006..9c1955f 100644
--- a/lib/bunyan.js
+++ b/lib/bunyan.js
@@ -478,7 +478,7 @@ function Logger(options, _childOptions, _childSimple) {
     if (this.serializers) {
         this._applySerializers(fields);
     }
-    if (!fields.hostname) {
+    if (!fields.hostname && !self.fields.hostname) {
         fields.hostname = os.hostname();
     }
     if (!fields.pid) {
diff --git a/test/child-behaviour.test.js b/test/child-behaviour.test.js
index f29ec7a..ddc2896 100644
--- a/test/child-behaviour.test.js
+++ b/test/child-behaviour.test.js
@@ -134,3 +134,28 @@ test('child can set level of inherited streams and add streams', function (t) {
 
     t.end();
 });
+
+// issue #291
+test('child should not lose parent "hostname"', function (t) {
+    var stream = new CapturingStream();
+    var dad = bunyan.createLogger({
+        name: 'hostname-test',
+        hostname: 'bar0',
+        streams: [ {
+            type: 'raw',
+            stream: stream,
+            level: 'info'
+        } ]
+    });
+    var son = dad.child({component: 'son'});
+
+    dad.info('HI');
+    son.info('hi');
+
+    t.equal(stream.recs.length, 2);
+    t.equal(stream.recs[0].hostname, 'bar0');
+    t.equal(stream.recs[1].hostname, 'bar0');
+    t.equal(stream.recs[1].component, 'son');
+
+    t.end();
+});