feat(pdk) kong.node.get_hostname (#6613)

kong/api/routes/kong.lua

@@ -1,4 +1,3 @@
-local utils = require "kong.tools.utils"
 local singletons = require "kong.singletons"
 local conf_loader = require "kong.conf_loader"
 local cjson = require "cjson"
@@ -76,7 +75,7 @@ return {
       return kong.response.exit(200, {
         tagline = tagline,
         version = version,
-        hostname = utils.get_hostname(),
+        hostname = knode.get_hostname(),
         node_id = node_id,
         timers = {
           running = ngx.timer.running_count(),

kong/clustering.lua

@@ -137,7 +137,7 @@ local function communicate(premature, conf)
 
   local c = assert(ws_client:new(WS_OPTS))
   local uri = "wss://" .. address .. "/v1/outlet?node_id=" ..
-              kong.node.get_id() .. "&node_hostname=" .. utils.get_hostname()
+              kong.node.get_id() .. "&node_hostname=" .. kong.node.get_hostname()
 
   local opts = {
     ssl_verify = true,

kong/pdk/node.lua

@@ -3,15 +3,19 @@
 -- @module kong.node
 
 local utils = require "kong.tools.utils"
+local ffi = require "ffi"
 
 
 local floor = math.floor
 local lower = string.lower
 local match = string.match
+local gsub = string.gsub
 local sort = table.sort
 local insert = table.insert
 local shared = ngx.shared
-
+local C             = ffi.C
+local ffi_new       = ffi.new
+local ffi_str       = ffi.string
 
 local NODE_ID_KEY = "kong:node_id"
 
@@ -227,6 +231,30 @@ local function new(self)
   end
 
 
+  ---
+  -- Returns the name used by the local machine
+  --
+  -- @function kong.node.get_hostname
+  -- @treturn string The local machine hostname
+  -- @usage
+  -- local hostname = kong.node.get_hostname()
+  function _NODE.get_hostname()
+    local SIZE = 253 -- max number of chars for a hostname
+
+    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+$", "")
+    end
+
+    local f = io.popen("/bin/hostname")
+    local hostname = f:read("*a") or ""
+    f:close()
+    return gsub(hostname, "\n$", "")
+  end
+
   return _NODE
 end
 

kong/reports.lua

@@ -2,6 +2,8 @@ local cjson = require "cjson.safe"
 local utils = require "kong.tools.utils"
 local constants = require "kong.constants"
 local counter = require "resty.counter"
+local knode = (kong and kong.node) and kong.node or
+              require "kong.pdk.node".new()
 
 
 local kong_dict = ngx.shared.kong
@@ -61,6 +63,8 @@ do
 
   local system_infos = utils.get_system_infos()
 
+  system_infos.hostname = system_infos.hostname or knode.get_hostname()
+
   -- <14>: syslog facility code 'log alert'
   _buffer[#_buffer + 1] = "<14>version=" .. meta._VERSION
 

kong/tools/utils.lua

@@ -88,28 +88,6 @@ _M.pack = function(...) return {n = select("#", ...), ...} end
 -- Explicitly honors the `n` field if given in the table, so it is `nil` safe
 _M.unpack = function(t, i, j) return unpack(t, i or 1, j or t.n or #t) end
 
---- Retrieves the hostname of the local machine
--- @return string  The hostname
-function _M.get_hostname()
-  local result
-  local SIZE = 128
-
-  local buf = ffi_new("unsigned char[?]", SIZE)
-  local res = C.gethostname(buf, SIZE)
-
-  if res == 0 then
-    local hostname = ffi_str(buf, SIZE)
-    result = gsub(hostname, "%z+$", "")
-  else
-    local f = io.popen("/bin/hostname")
-    local hostname = f:read("*a") or ""
-    f:close()
-    result = gsub(hostname, "\n$", "")
-  end
-
-  return result
-end
-
 do
   local _system_infos
 
@@ -118,9 +96,7 @@ do
       return _system_infos
     end
 
-    _system_infos = {
-      hostname = _M.get_hostname()
-    }
+    _system_infos = {}
 
     local ok, _, stdout = pl_utils.executeex("getconf _NPROCESSORS_ONLN")
     if ok then

spec/01-unit/05-utils_spec.lua

@@ -3,19 +3,11 @@ local pl_path = require "pl.path"
 
 describe("Utils", function()
 
-  describe("get_hostname()", function()
-    it("should retrieve the hostname", function()
-      assert.is_string(utils.get_hostname())
-    end)
-  end)
-
   describe("get_system_infos()", function()
     it("retrieves various host infos", function()
       local infos = utils.get_system_infos()
       assert.is_number(infos.cores)
-      assert.is_string(infos.hostname)
       assert.is_string(infos.uname)
-      assert.not_matches("\n$", infos.hostname)
       assert.not_matches("\n$", infos.uname)
     end)
     it("caches the result", function()

t/01-pdk/12-node/00-phase_checks.t

@@ -55,6 +55,18 @@ qq{
                 log           = true,
                 admin_api     = true,
             },
+            {
+                method        = "get_hostname",
+                args          = {},
+                init_worker   = true,
+                certificate   = "pending",
+                rewrite       = true,
+                access        = true,
+                header_filter = true,
+                body_filter   = true,
+                log           = true,
+                admin_api     = true,
+            },
         }
 
         phase_check_functions(phases.init_worker)

t/01-pdk/12-node/03-get_hostname.t

@@ -0,0 +1,35 @@
+use strict;
+use warnings FATAL => 'all';
+use Test::Nginx::Socket::Lua;
+use t::Util;
+
+plan tests => repeat_each() * (blocks() * 3);
+
+run_tests();
+
+__DATA__
+
+=== TEST 1: node.get_id() returns node identifier
+--- http_config eval
+qq{
+    $t::Util::HttpConfig
+
+    lua_shared_dict kong 24k;
+}
+--- config
+    location = /t {
+        content_by_lua_block {
+            local PDK = require "kong.pdk"
+            local pdk = PDK.new()
+
+            math.randomseed(ngx.time())
+
+            ngx.say(pdk.node.get_id())
+        }
+    }
+--- request
+GET /t
+--- response_body_like
+^([a-zA-Z0-9](?:(?:[a-zA-Z0-9-]*|(?<!-)\.(?![-.]))*[a-zA-Z0-9]+)?)$
+--- no_error_log
+[error]