From a80a8be42a15d4111236a899bd0d8cf76d5fb3e5 Mon Sep 17 00:00:00 2001
From: suryaparua-official <surya.exce@gmail.com>
Date: Tue, 12 May 2026 04:43:48 +0000
Subject: [PATCH 1/3] fix(limit-count): correct error() call in gen_limit_key

The second argument to Lua's error(msg, level) must be an integer
(stack level), not a string. Passing core.json.encode(parent) as
the level causes LuaJIT to raise:
  bad argument #2 to error (number expected, got string)

Fix: concatenate the JSON into the message string using '..'.

Also add a test case to verify the error message is correct
when _meta.parent is missing.

Fixes #13357
---
 apisix/plugins/limit-count/init.lua |  2 +-
 t/plugin/limit-count5.t             | 42 +++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/apisix/plugins/limit-count/init.lua b/apisix/plugins/limit-count/init.lua
index ea1d0158e5a1..75d9dcc35356 100644
--- a/apisix/plugins/limit-count/init.lua
+++ b/apisix/plugins/limit-count/init.lua
@@ -259,7 +259,7 @@ local function gen_limit_key(conf, ctx, key)
     -- A route which reuses a previous route's ID will inherits its counter.
     local parent = conf._meta and conf._meta.parent
     if not parent or not parent.resource_key then
-        error("failed to generate key invalid parent: ", core.json.encode(parent))
+        error("failed to generate key invalid parent: " .. core.json.encode(parent))
     end
 
     local new_key = parent.resource_key .. ':' .. apisix_plugin.conf_version(conf)
diff --git a/t/plugin/limit-count5.t b/t/plugin/limit-count5.t
index 15a3e0ba4467..a0d807d52732 100644
--- a/t/plugin/limit-count5.t
+++ b/t/plugin/limit-count5.t
@@ -307,3 +307,45 @@ peek3: 3
 commit2: 0
 peek4: 0
 commit3: rejected
+
+=== TEST 9: error() call in gen_limit_key produces correct error message when parent is missing
+--- config
+    location /t {
+        content_by_lua_block {
+            local init = require("apisix.plugins.limit-count.init")
+            local conf = {
+                policy = "local",
+                count = 5,
+                time_window = 60,
+                key = "remote_addr",
+                key_type = "var",
+                rejected_code = 503,
+                allow_degradation = false,
+                show_limit_quota_header = true,
+                _meta = {}
+                -- _meta.parent is intentionally missing
+            }
+            local ctx = {
+                var = {remote_addr = "127.0.0.1"},
+                conf_version = 1,
+                conf_type = "route"
+            }
+            local ok, err = pcall(init.rate_limit, conf, ctx, "limit-count", 1)
+            if not ok then
+                -- error message should contain the JSON of parent (null)
+                if err:find("failed to generate key invalid parent") then
+                    ngx.say("correct error message")
+                else
+                    ngx.say("wrong error: " .. tostring(err))
+                end
+            else
+                ngx.say("should have errored")
+            end
+        }
+    }
+--- request
+GET /t
+--- response_body
+correct error message
+--- no_error_log
+[alert]

From 082c28572e63f43a2f3b4e098b66b6352d411000 Mon Sep 17 00:00:00 2001
From: suryaparua-official <surya.exce@gmail.com>
Date: Thu, 14 May 2026 15:18:40 +0000
Subject: [PATCH 2/3] test(limit-count): add three empty lines between tests

---
 t/plugin/limit-count5.t | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/t/plugin/limit-count5.t b/t/plugin/limit-count5.t
index a0d807d52732..7d07b369c0d2 100644
--- a/t/plugin/limit-count5.t
+++ b/t/plugin/limit-count5.t
@@ -308,6 +308,8 @@ commit2: 0
 peek4: 0
 commit3: rejected
 
+
+
 === TEST 9: error() call in gen_limit_key produces correct error message when parent is missing
 --- config
     location /t {

From d0321843f2edaa9298de7b9f87ae03d8c1c9b681 Mon Sep 17 00:00:00 2001
From: suryaparua-official <surya.exce@gmail.com>
Date: Wed, 27 May 2026 02:01:54 +0000
Subject: [PATCH 3/3] fix(dns): correct error() call in dns client
 initialization

Similar to the fix in limit-count plugin, the error() call in
apisix/discovery/dns/init.lua was passing a string as the second
argument instead of an integer stack level.
---
 apisix/discovery/dns/init.lua | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/apisix/discovery/dns/init.lua b/apisix/discovery/dns/init.lua
index 601de0ebc9ee..197b7580d996 100644
--- a/apisix/discovery/dns/init.lua
+++ b/apisix/discovery/dns/init.lua
@@ -78,7 +78,7 @@ function _M.init_worker()
 
     local client, err = core.dns_client.new(opts)
     if not client then
-        error("failed to init the dns client: ", err)
+        error("failed to init the dns client: " .. (err or "unknown"))
         return
     end