From e22a8d891a900ee25f08d2f111ec8bd69ff3c4bc Mon Sep 17 00:00:00 2001
From: Abhishek Choudhary <shreemaan.abhishek@gmail.com>
Date: Mon, 13 Nov 2023 14:54:08 +0545
Subject: [PATCH 1/6] fix regex pattern

---
 apisix/core/utils.lua | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/apisix/core/utils.lua b/apisix/core/utils.lua
index 70531e7c1fa9..f33c54b9d394 100644
--- a/apisix/core/utils.lua
+++ b/apisix/core/utils.lua
@@ -292,7 +292,7 @@ local resolve_var
 do
     local _ctx
     local n_resolved
-    local pat = [[(?<!\\)\$\{?(\w+)\}?]]
+    local pat = [[(?<!\\)\$(\{(\w+)\}|(\w+))]]
     local _escaper
 
     local function resolve(m)

From d1e4a26960f215748c237b89d547fec391a2d8b0 Mon Sep 17 00:00:00 2001
From: Abhishek Choudhary <shreemaan.abhishek@gmail.com>
Date: Mon, 13 Nov 2023 15:02:58 +0545
Subject: [PATCH 2/6] add test

---
 t/plugin/fault-injection2.t | 44 +++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/t/plugin/fault-injection2.t b/t/plugin/fault-injection2.t
index 0ba23f536069..b77848ddaf96 100644
--- a/t/plugin/fault-injection2.t
+++ b/t/plugin/fault-injection2.t
@@ -140,3 +140,47 @@ GET /hello
 h1: v1
 h2: 2
 h3: /hello
+
+
+
+=== TEST 4: closing curly brace not should not be a part of variable
+--- config
+ location /t {
+           content_by_lua_block {
+               local t = require("lib.test_admin").test
+               local code, body = t('/apisix/admin/routes/1',
+                    ngx.HTTP_PUT,
+                    [=[{
+                            "plugins": {
+                               "fault-injection": {
+                                   "abort": {
+                                      "http_status": 200,
+                                      "body": "{\"count\": $arg_count}"
+                                   }
+                               }
+                            },
+                            "upstream": {
+                               "nodes": {
+                                   "127.0.0.1:1980": 1
+                               },
+                               "type": "roundrobin"
+                            },
+                            "uri": "/hello"
+                        }]=]
+                   )
+               if code >= 300 then
+                   ngx.status = code
+               end
+               ngx.say(body)
+           }
+       }
+--- response_body
+passed
+
+
+
+=== TEST 5: inject header
+--- request
+GET /hello?count=2
+--- response_body chomp
+{"count": 2}

From 77f7d1d5951450c96ba3cac8519c2ecdc4d701fd Mon Sep 17 00:00:00 2001
From: Abhishek Choudhary <shreemaan.abhishek@gmail.com>
Date: Tue, 14 Nov 2023 07:27:50 +0545
Subject: [PATCH 3/6] reindex

---
 t/plugin/fault-injection2.t | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/t/plugin/fault-injection2.t b/t/plugin/fault-injection2.t
index b77848ddaf96..bd28f6bfa5d2 100644
--- a/t/plugin/fault-injection2.t
+++ b/t/plugin/fault-injection2.t
@@ -143,7 +143,7 @@ h3: /hello
 
 
 
-=== TEST 4: closing curly brace not should not be a part of variable
+=== TEST 6: closing curly brace not should not be a part of variable
 --- config
  location /t {
            content_by_lua_block {
@@ -179,7 +179,7 @@ passed
 
 
 
-=== TEST 5: inject header
+=== TEST 7: test route
 --- request
 GET /hello?count=2
 --- response_body chomp

From c276f5597eaf5b2101d7d8a3255dc086b1bde1dc Mon Sep 17 00:00:00 2001
From: Abhishek Choudhary <shreemaan.abhishek@gmail.com>
Date: Tue, 14 Nov 2023 07:28:11 +0545
Subject: [PATCH 4/6] avoid evaluating capture with braces

---
 apisix/core/utils.lua | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/apisix/core/utils.lua b/apisix/core/utils.lua
index f33c54b9d394..6c0abc2ad269 100644
--- a/apisix/core/utils.lua
+++ b/apisix/core/utils.lua
@@ -296,7 +296,11 @@ do
     local _escaper
 
     local function resolve(m)
-        local v = _ctx[m[1]]
+        local i = 1
+        if m[1]:byte(1) == 123 then
+            i = 2
+        end
+        local v = _ctx[m[i]]
         if v == nil then
             return ""
         end

From f30fe75ce317d4d2e7279ec1910d9ee88caee624 Mon Sep 17 00:00:00 2001
From: Abhishek Choudhary <shreemaan.abhishek@gmail.com>
Date: Tue, 14 Nov 2023 08:59:45 +0545
Subject: [PATCH 5/6] add comment

---
 apisix/core/utils.lua | 1 +
 1 file changed, 1 insertion(+)

diff --git a/apisix/core/utils.lua b/apisix/core/utils.lua
index 6c0abc2ad269..a759135c6ccd 100644
--- a/apisix/core/utils.lua
+++ b/apisix/core/utils.lua
@@ -297,6 +297,7 @@ do
 
     local function resolve(m)
         local i = 1
+        -- if first capture's first char is "{" evaluate the second capture
         if m[1]:byte(1) == 123 then
             i = 2
         end

From 533a626a7c4ec65ec62cfc7216a066d990783742 Mon Sep 17 00:00:00 2001
From: Abhishek Choudhary <shreemaan.abhishek@gmail.com>
Date: Tue, 21 Nov 2023 19:38:55 +0545
Subject: [PATCH 6/6] optimize

---
 apisix/core/utils.lua | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/apisix/core/utils.lua b/apisix/core/utils.lua
index a759135c6ccd..adca3d856d8c 100644
--- a/apisix/core/utils.lua
+++ b/apisix/core/utils.lua
@@ -296,12 +296,9 @@ do
     local _escaper
 
     local function resolve(m)
-        local i = 1
-        -- if first capture's first char is "{" evaluate the second capture
-        if m[1]:byte(1) == 123 then
-            i = 2
-        end
-        local v = _ctx[m[i]]
+        local variable = m[2] or m[3]
+        local v = _ctx[variable]
+
         if v == nil then
             return ""
         end