From 16aa4b67abfee8f1e9ccbb07949c0e331d71a8e6 Mon Sep 17 00:00:00 2001
From: Water-Melon <melon-c@hotmail.com>
Date: Fri, 25 Oct 2024 03:42:15 +0000
Subject: [PATCH 1/3] fix(loggly): fix the error caused by the missing
 /bin/hostname

1. Refactor the PDK's get_hostname to use only the gethostname system call to retrieve the hostname.
2. Loggly uses the PDK's get_hostname to retrieve the hostname.

FTI-6046
---
 .../kong/fix-loggly-hostname-notfound.yml          |  2 ++
 kong/pdk/node.lua                                  | 14 +++++++-------
 kong/plugins/loggly/handler.lua                    | 10 +---------
 3 files changed, 10 insertions(+), 16 deletions(-)
 create mode 100644 changelog/unreleased/kong/fix-loggly-hostname-notfound.yml

diff --git a/changelog/unreleased/kong/fix-loggly-hostname-notfound.yml b/changelog/unreleased/kong/fix-loggly-hostname-notfound.yml
new file mode 100644
index 000000000000..5e2cadb73bdd
--- /dev/null
+++ b/changelog/unreleased/kong/fix-loggly-hostname-notfound.yml
@@ -0,0 +1,2 @@
+message: "**loggly**: fixed the error caused by the missing `/bin/hostname`."
+type: bugfix
diff --git a/kong/pdk/node.lua b/kong/pdk/node.lua
index 9302c17cde1a..23f83ca449d1 100644
--- a/kong/pdk/node.lua
+++ b/kong/pdk/node.lua
@@ -252,15 +252,15 @@ local function new(self)
     local buf = ffi_new("unsigned char[?]", SIZE)
     local res = C.gethostname(buf, SIZE)
 
-    if res == 0 then
-      local hostname = ffi_str(buf, SIZE)
-      return gsub(hostname, "%z+$", "")
+    if res ~= 0 then
+      -- Return an empty string "" instead of nil and error message,
+      -- because strerror is not thread-safe and the behavior of strerror_r
+      -- is inconsistent across different systems.
+      return ""
     end
 
-    local f = io.popen("/bin/hostname")
-    local hostname = f:read("*a") or ""
-    f:close()
-    return gsub(hostname, "\n$", "")
+    local hostname = ffi_str(buf, SIZE)
+    return gsub(hostname, "%z+$", "")
   end
 
 
diff --git a/kong/plugins/loggly/handler.lua b/kong/plugins/loggly/handler.lua
index 9288adb37b7c..39e70547e66f 100644
--- a/kong/plugins/loggly/handler.lua
+++ b/kong/plugins/loggly/handler.lua
@@ -1,6 +1,7 @@
 local cjson = require "cjson"
 local sandbox = require "kong.tools.sandbox".sandbox
 local kong_meta = require "kong.meta"
+local get_host_name = kong.node.get_hostname
 
 
 local kong = kong
@@ -16,15 +17,6 @@ local insert = table.insert
 local sandbox_opts = { env = { kong = kong, ngx = ngx } }
 
 
-local function get_host_name()
-  local f = io.popen("/bin/hostname")
-  local hostname = f:read("*a") or ""
-  f:close()
-  hostname = string.gsub(hostname, "\n$", "")
-  return hostname
-end
-
-
 local HOSTNAME = get_host_name()
 local SENDER_NAME = "kong"
 local LOG_LEVELS = {

From 7cedd871349dc054cd823b6897f87e18c95d3cd5 Mon Sep 17 00:00:00 2001
From: Water-Melon <melon-c@hotmail.com>
Date: Mon, 28 Oct 2024 08:48:38 +0000
Subject: [PATCH 2/3] cache hostname

---
 kong/pdk/node.lua | 27 ++++++++++++++++-----------
 1 file changed, 16 insertions(+), 11 deletions(-)

diff --git a/kong/pdk/node.lua b/kong/pdk/node.lua
index 23f83ca449d1..fe8bfbc72392 100644
--- a/kong/pdk/node.lua
+++ b/kong/pdk/node.lua
@@ -57,7 +57,9 @@ end
 
 
 local function new(self)
-  local _NODE = {}
+  local _NODE = {
+    hostname = nil,
+  }
 
 
   ---
@@ -247,20 +249,23 @@ local function new(self)
   -- @usage
   -- local hostname = kong.node.get_hostname()
   function _NODE.get_hostname()
-    local SIZE = 253 -- max number of chars for a hostname
+    if not _NODE.hostname then
+      local SIZE = 253 -- max number of chars for a hostname
 
-    local buf = ffi_new("unsigned char[?]", SIZE)
-    local res = C.gethostname(buf, SIZE)
+      local buf = ffi_new("unsigned char[?]", SIZE)
+      local res = C.gethostname(buf, SIZE)
 
-    if res ~= 0 then
-      -- Return an empty string "" instead of nil and error message,
-      -- because strerror is not thread-safe and the behavior of strerror_r
-      -- is inconsistent across different systems.
-      return ""
+      if res ~= 0 then
+        -- Return an empty string "" instead of nil and error message,
+        -- because strerror is not thread-safe and the behavior of strerror_r
+        -- is inconsistent across different systems.
+        return ""
+      end
+
+      _NODE.hostname = gsub(ffi_str(buf, SIZE), "%z+$", "")
     end
 
-    local hostname = ffi_str(buf, SIZE)
-    return gsub(hostname, "%z+$", "")
+    return _NODE.hostname
   end
 
 

From 73d40c8a3159899f8662f738bff22aab8cc7b978 Mon Sep 17 00:00:00 2001
From: Water-Melon <melon-c@hotmail.com>
Date: Mon, 28 Oct 2024 08:48:47 +0000
Subject: [PATCH 3/3] update changelog

---
 changelog/unreleased/kong/fix-loggly-hostname-notfound.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/changelog/unreleased/kong/fix-loggly-hostname-notfound.yml b/changelog/unreleased/kong/fix-loggly-hostname-notfound.yml
index 5e2cadb73bdd..23ad46d028a5 100644
--- a/changelog/unreleased/kong/fix-loggly-hostname-notfound.yml
+++ b/changelog/unreleased/kong/fix-loggly-hostname-notfound.yml
@@ -1,2 +1,2 @@
-message: "**loggly**: fixed the error caused by the missing `/bin/hostname`."
+message: "**Loggly**: Fixed an issue where `/bin/hostname` missing caused an error warning on startup."
 type: bugfix