feat(gui): added a new feature to support proxy Admin API via Gui.

kong.conf.default

@@ -2034,10 +2034,13 @@
 
 #admin_gui_api_url =    # Hierarchical part of a URI which is composed
                         # optionally of a host, port, and path at which the
-                        # Admin API accepts HTTP or HTTPS traffic. When
-                        # this config is disabled, Kong Manager will
-                        # use the window protocol + host and append the
-                        # resolved admin_listen HTTP/HTTPS port.
+                        # Admin API accepts HTTP or HTTPS traffic.
+                        # 
+                        # Examples:
+                        # - http://localhost:8001
+                        # - http://127.0.0.1:8001
+                        # - https://admin.konghq.com:8444
+                        # - https://127.0.0.1:8444
 
 #admin_gui_ssl_cert =   # The SSL certificate for `admin_gui_listen` values
                         # with SSL enabled.

kong/admin_gui/init.lua

@@ -4,24 +4,15 @@ local fmt = string.format
 local insert = table.insert
 local concat = table.concat
 
-local select_listener = utils.select_listener
 local prepare_variable = utils.prepare_variable
 
 local _M = {}
 
 function _M.generate_kconfig(kong_config)
-  local api_listen = select_listener(kong_config.admin_listeners, {ssl = false})
-  local api_port = api_listen and api_listen.port
-
-  local api_ssl_listen = select_listener(kong_config.admin_listeners, {ssl = true})
-  local api_ssl_port = api_ssl_listen and api_ssl_listen.port
-
   local configs = {
     ADMIN_GUI_URL = prepare_variable(kong_config.admin_gui_url),
     ADMIN_GUI_PATH = prepare_variable(kong_config.admin_gui_path),
     ADMIN_API_URL = prepare_variable(kong_config.admin_gui_api_url),
-    ADMIN_API_PORT = prepare_variable(api_port),
-    ADMIN_API_SSL_PORT = prepare_variable(api_ssl_port),
     ANONYMOUS_REPORTS = prepare_variable(kong_config.anonymous_reports),
   }
 

kong/init.lua

@@ -77,6 +77,7 @@ local certificate = require "kong.runloop.certificate"
 local concurrency = require "kong.concurrency"
 local cache_warmup = require "kong.cache.warmup"
 local balancer = require "kong.runloop.balancer"
+local utils = require "kong.admin_gui.utils"
 local kong_error_handlers = require "kong.error_handlers"
 local plugin_servers = require "kong.runloop.plugin_servers"
 local lmdb_txn = require "resty.lmdb.transaction"
@@ -124,6 +125,7 @@ local set_current_peer = ngx_balancer.set_current_peer
 local set_timeouts     = ngx_balancer.set_timeouts
 local set_more_tries   = ngx_balancer.set_more_tries
 local enable_keepalive = ngx_balancer.enable_keepalive
+local select_listener  = utils.select_listener
 
 
 local time_ns            = kong_time.time_ns
@@ -1938,6 +1940,20 @@ function Kong.admin_gui_kconfig_content()
   end
 end
 
+function Kong.admin_gui_api_balancer()
+  local admin_listeners = kong.configuration.admin_listeners
+  local listener = select_listener(admin_listeners, { ssl = true })
+  if not listener then
+    listener = select_listener(admin_listeners, { ssl = false })
+  end
+
+  local ok, err = set_current_peer(listener.ip, listener.port)
+  if not ok then
+    ngx.log(ngx.ERR, "failed to set the Admin Api balancer: ", err)
+    return ngx.exit(500)
+  end
+end
+
 function Kong.admin_gui_log()
   if kong.configuration.anonymous_reports then
     reports.admin_gui_log(ngx.ctx)

kong/templates/nginx_kong.lua

@@ -84,6 +84,16 @@ upstream kong_upstream {
     }
 }
 
+> if (role == "control_plane" or role == "traditional") and #admin_listeners > 0 then
+upstream kong_admin_gui_api {
+  server 0.0.0.1;
+
+  balancer_by_lua_block {
+    Kong.admin_gui_api_balancer()
+  }
+}
+> end
+
 server {
     server_name kong;
 > for _, entry in ipairs(proxy_listeners) do

kong/templates/nginx_kong_gui_include.lua

@@ -23,6 +23,25 @@ location = $(admin_gui_path_prefix)/kconfig.js {
     }
 }
 
+> if (role == "control_plane" or role == "traditional") and #admin_listeners > 0 then
+location ~* $(admin_gui_path_prefix)/gateway/api {
+    set_by_lua_block $backend {
+        local utils = require "kong.admin_gui.utils"
+        local listener = utils.select_listener(kong.configuration.admin_listeners, { ssl = true })
+        if listener then
+            return "https://kong_admin_gui_api"
+        else
+            return "http://kong_admin_gui_api"
+        end
+    }
+    rewrite ^$(admin_gui_path_prefix)/gateway/api(/.*)$ $1 break;
+    proxy_pass $backend;
+    proxy_set_header Host $host;
+    proxy_set_header X-Real-IP $remote_addr;
+    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+}
+> end
+
 location = $(admin_gui_path_prefix)/favicon.ico {
     root gui;
 

spec/01-unit/29-admin_gui/02-admin_gui_template_spec.lua

@@ -67,8 +67,6 @@ describe("admin_gui template", function()
       assert.matches("'ADMIN_GUI_URL': 'http://0.0.0.0:8002'", kconfig_content, nil, true)
       assert.matches("'ADMIN_GUI_PATH': '/manager'", kconfig_content, nil, true)
       assert.matches("'ADMIN_API_URL': 'https://admin-reference.kong-cloud.test'", kconfig_content, nil, true)
-      assert.matches("'ADMIN_API_PORT': '8001'", kconfig_content, nil, true)
-      assert.matches("'ADMIN_API_SSL_PORT': '8444'", kconfig_content, nil, true)
     end)
 
     it("should regenerates the appropriate kconfig from another call", function()
@@ -86,8 +84,6 @@ describe("admin_gui template", function()
       assert.matches("'ADMIN_GUI_URL': 'http://admin-test.example.com'", new_content, nil, true)
       assert.matches("'ADMIN_GUI_PATH': '/manager'", new_content, nil, true)
       assert.matches("'ADMIN_API_URL': 'http://localhost:8001'", new_content, nil, true)
-      assert.matches("'ADMIN_API_PORT': '8001'", new_content, nil, true)
-      assert.matches("'ADMIN_API_SSL_PORT': '8444'", new_content, nil, true)
     end)
   end)
 
@@ -148,8 +144,6 @@ describe("admin_gui template", function()
 
       assert.matches("'ADMIN_GUI_URL': 'http://0.0.0.0:8002'", kconfig_content, nil, true)
       assert.matches("'ADMIN_API_URL': '0.0.0.0:8001'", kconfig_content, nil, true)
-      assert.matches("'ADMIN_API_PORT': '8001'", kconfig_content, nil, true)
-      assert.matches("'ADMIN_API_SSL_PORT': '8444'", kconfig_content, nil, true)
       assert.matches("'ANONYMOUS_REPORTS': 'false'", kconfig_content, nil, true)
     end)
 
@@ -166,8 +160,6 @@ describe("admin_gui template", function()
       -- test configuration values against template
       assert.matches("'ADMIN_GUI_URL': 'http://admin-test.example.com'", new_content, nil, true)
       assert.matches("'ADMIN_API_URL': '0.0.0.0:8001'", new_content, nil, true)
-      assert.matches("'ADMIN_API_PORT': '8001'", new_content, nil, true)
-      assert.matches("'ADMIN_API_SSL_PORT': '8444'", new_content, nil, true)
       assert.matches("'ANONYMOUS_REPORTS': 'true'", new_content, nil, true)
     end)
   end)