diff --git a/apisix/core/table.lua b/apisix/core/table.lua
index 4ad92caa104d2..942a7f3b438ab 100644
--- a/apisix/core/table.lua
+++ b/apisix/core/table.lua
@@ -59,6 +59,22 @@ function _M.set(tab, ...)
 end
 
 
+function _M.try_read_attr(tab, ...)
+    local count = select('#', ...)
+
+    for i = 1, count do
+        local attr = select(i, ...)
+        if type(tab) ~= "table" then
+            return nil
+        end
+
+        tab = tab[attr]
+    end
+
+    return tab
+end
+
+
 -- only work under lua51 or luajit
 function _M.setmt__gc(t, mt)
     local prox = newproxy(true)
diff --git a/apisix/plugins/hmac-auth.lua b/apisix/plugins/hmac-auth.lua
index 9f6e6d15be904..5ad91f887a7ca 100644
--- a/apisix/plugins/hmac-auth.lua
+++ b/apisix/plugins/hmac-auth.lua
@@ -16,7 +16,6 @@
 --
 local ngx        = ngx
 local type       = type
-local select     = select
 local abs        = math.abs
 local ngx_time   = ngx.time
 local ngx_re     = require("ngx.re")
@@ -99,21 +98,6 @@ local hmac_funcs = {
 }
 
 
-local function try_attr(t, ...)
-    local tbl = t
-    local count = select('#', ...)
-    for i = 1, count do
-        local attr = select(i, ...)
-        tbl = tbl[attr]
-        if type(tbl) ~= "table" then
-            return false
-        end
-    end
-
-    return true
-end
-
-
 local function array_to_map(arr)
     local map = core.table.new(0, #arr)
     for _, v in ipairs(arr) do
@@ -328,7 +312,7 @@ local function get_params(ctx)
     local date_key = DATE_KEY
     local signed_headers_key = SIGNED_HEADERS_KEY
 
-    if try_attr(local_conf, "plugin_attr", "hmac-auth") then
+    if core.table.try_read_attr(local_conf, "plugin_attr", "hmac-auth") then
         local attr = local_conf.plugin_attr["hmac-auth"]
         access_key = attr.access_key or access_key
         signature_key = attr.signature_key or signature_key
diff --git a/apisix/plugins/log-rotate.lua b/apisix/plugins/log-rotate.lua
index 22d38b1ae7d88..883a72b0bc30f 100644
--- a/apisix/plugins/log-rotate.lua
+++ b/apisix/plugins/log-rotate.lua
@@ -23,8 +23,6 @@ local lfs = require("lfs")
 local io = io
 local os = os
 local table = table
-local select = select
-local type = type
 local string = string
 local local_conf
 
@@ -152,25 +150,11 @@ local function scan_log_folder()
 end
 
 
-local function try_attr(t, ...)
-    local count = select('#', ...)
-    for i = 1, count do
-        local attr = select(i, ...)
-        t = t[attr]
-        if type(t) ~= "table" then
-            return false
-        end
-    end
-
-    return true
-end
-
-
 local function rotate()
     local local_conf = core.config.local_conf()
     local interval = INTERVAL
     local max_kept = MAX_KEPT
-    if try_attr(local_conf, "plugin_attr", "log-rotate") then
+    if core.table.try_read_attr(local_conf, "plugin_attr", "log-rotate") then
         local attr = local_conf.plugin_attr["log-rotate"]
         interval = attr.interval or interval
         max_kept = attr.max_kept or max_kept
diff --git a/apisix/plugins/skywalking.lua b/apisix/plugins/skywalking.lua
index 26aeb60bff96a..c62ba8ad5fe4a 100644
--- a/apisix/plugins/skywalking.lua
+++ b/apisix/plugins/skywalking.lua
@@ -19,8 +19,6 @@ local core = require("apisix.core")
 local process = require("ngx.process")
 local ngx = ngx
 local math = math
-local select = select
-local type = type
 local require = require
 
 local plugin_name = "skywalking"
@@ -103,28 +101,15 @@ function _M.log(conf, ctx)
 end
 
 
-local function try_read_attr(t, ...)
-    local count = select('#', ...)
-    for i = 1, count do
-        local attr = select(i, ...)
-        if type(t) ~= "table" then
-            return nil
-        end
-        t = t[attr]
-    end
-
-    return t
-end
-
-
 function _M.init()
     if process.type() ~= "worker" and process.type() ~= "single" then
         return
     end
 
     local local_conf = core.config.local_conf()
-    local local_plugin_info = try_read_attr(local_conf, "plugin_attr",
-                                            plugin_name) or {}
+    local local_plugin_info = core.table.try_read_attr(local_conf,
+                                                       "plugin_attr",
+                                                       plugin_name) or {}
     local_plugin_info = core.table.clone(local_plugin_info)
     local ok, err = core.schema.check(metadata_schema, local_plugin_info)
     if not ok then
diff --git a/t/core/table.t b/t/core/table.t
index 59c887538e7d1..69bf70d3d54c8 100644
--- a/t/core/table.t
+++ b/t/core/table.t
@@ -77,3 +77,29 @@ GET /t
 ok
 --- no_error_log
 [error]
+
+
+
+=== TEST 3: try_read_attr
+--- config
+    location /t {
+        content_by_lua_block {
+            local core = require("apisix.core")
+            local try_read_attr = core.table.try_read_attr
+
+            local t = {level1 = {level2 = "value"}}
+
+            local v = try_read_attr(t, "level1", "level2")
+            ngx.say(v)
+
+            local v2 = try_read_attr(t, "level1", "level3")
+            ngx.say(v2)
+        }
+    }
+--- request
+GET /t
+--- response_body
+value
+nil
+--- no_error_log
+[error]