fix: preserve uri args if path has not been modified (#13080)

Author: shreemaan-abhishek

apisix/plugins/ext-plugin/init.lua

@@ -706,10 +706,10 @@ local rpc_handlers = {
                 end
 
                 core.request.set_uri_args(ctx, args)
+            end
 
-                if path then
-                    var.upstream_uri = path .. '?' .. var.args
-                end
+            if path then
+                var.upstream_uri = path .. (var.is_args or '') .. (var.args or '')
             end
         end
 

t/lib/ext-plugin.lua

@@ -399,6 +399,13 @@ function _M.go(case)
             local action = http_req_call_rewrite.End(builder)
             build_action(action, http_req_call_action.Rewrite)
 
+        elseif case.rewrite_path_only then
+            local path = builder:CreateString("/plugin_proxy_rewrite_args")
+            http_req_call_rewrite.Start(builder)
+            http_req_call_rewrite.AddPath(builder, path)
+            local action = http_req_call_rewrite.End(builder)
+            build_action(action, http_req_call_action.Rewrite)
+
         elseif case.rewrite_bad_path == true then
             local path = builder:CreateString("/plugin_proxy_rewrite_args?a=2")
             http_req_call_rewrite.Start(builder)

t/plugin/ext-plugin/http-req-call.t

@@ -807,3 +807,77 @@ cat
     }
 --- response_body
 abc
+
+
+
+=== TEST 29: rewrite path only (preserve original query args)
+--- config
+    location /t {
+        content_by_lua_block {
+            local json = require("toolkit.json")
+            local t = require("lib.test_admin")
+
+            local code, message, res = t.test('/apisix/admin/routes/1',
+                ngx.HTTP_PUT,
+                 [[{
+                    "uri": "/hello",
+                    "plugins": {
+                        "ext-plugin-pre-req": {
+                        }
+                    },
+                    "upstream": {
+                        "nodes": {
+                            "127.0.0.1:1980": 1
+                        },
+                        "type": "roundrobin"
+                    }
+                }]]
+            )
+
+            if code >= 300 then
+                ngx.status = code
+                ngx.say(message)
+                return
+            end
+
+            ngx.say(message)
+        }
+    }
+--- response_body
+passed
+
+
+
+=== TEST 30: hit (original query args should be preserved when only path is rewritten)
+--- request
+GET /hello?c=foo&d=bar
+--- extra_stream_config
+    server {
+        listen unix:$TEST_NGINX_HTML_DIR/nginx.sock;
+
+        content_by_lua_block {
+            local ext = require("lib.ext-plugin")
+            ext.go({rewrite_path_only = true})
+        }
+    }
+--- response_body
+uri: /plugin_proxy_rewrite_args
+c: foo
+d: bar
+
+
+
+=== TEST 31: hit (when no uri args are passed, there are no failures)
+--- request
+GET /hello
+--- extra_stream_config
+    server {
+        listen unix:$TEST_NGINX_HTML_DIR/nginx.sock;
+
+        content_by_lua_block {
+            local ext = require("lib.ext-plugin")
+            ext.go({rewrite_path_only = true})
+        }
+    }
+--- response_body
+uri: /plugin_proxy_rewrite_args