Feat/wrpc (#8357)

This commit add the wRPC protocol and uses it for the DP/CP connection in hybrid mode.

The wRPC protocol is a generic, bidirectional RPC protocol that allows multiple services on the same persistent (WebSocket) connection.

kong-2.8.0-0.rockspec

@@ -67,6 +67,8 @@ build = {
     ["kong.clustering"] = "kong/clustering/init.lua",
     ["kong.clustering.data_plane"] = "kong/clustering/data_plane.lua",
     ["kong.clustering.control_plane"] = "kong/clustering/control_plane.lua",
+    ["kong.clustering.wrpc_data_plane"] = "kong/clustering/wrpc_data_plane.lua",
+    ["kong.clustering.wrpc_control_plane"] = "kong/clustering/wrpc_control_plane.lua",
     ["kong.clustering.compat.removed_fields"] = "kong/clustering/compat/removed_fields.lua",
 
     ["kong.cluster_events"] = "kong/cluster_events/init.lua",
@@ -136,6 +138,9 @@ build = {
     ["kong.tools.sandbox"] = "kong/tools/sandbox.lua",
     ["kong.tools.uri"] = "kong/tools/uri.lua",
     ["kong.tools.kong-lua-sandbox"] = "kong/tools/kong-lua-sandbox.lua",
+    ["kong.tools.protobuf"] = "kong/tools/protobuf.lua",
+    ["kong.tools.wrpc"] = "kong/tools/wrpc.lua",
+    ["kong.tools.channel"] = "kong/tools/channel.lua",
 
     ["kong.runloop.handler"] = "kong/runloop/handler.lua",
     ["kong.runloop.certificate"] = "kong/runloop/certificate.lua",

kong/clustering/init.lua

@@ -130,7 +130,20 @@ function _M.new(conf)
   local key = assert(pl_file.read(conf.cluster_cert_key))
   self.cert_key = assert(ssl.parse_pem_priv_key(key))
 
-  self.child = require("kong.clustering." .. conf.role).new(self)
+  print("role: ", conf.role, "  protocol: ", conf.cluster_protocol)
+
+  if conf.role == "control_plane" then
+    self.json_handler = require("kong.clustering.control_plane").new(self)
+    self.wrpc_handler = require("kong.clustering.wrpc_control_plane").new(self)
+
+  else
+    local clustering_submodule = conf.role
+    if conf.cluster_protocol == "wrpc" then
+      clustering_submodule = "wrpc_" .. clustering_submodule
+    end
+
+    self.child = require("kong.clustering." .. clustering_submodule).new(self)
+  end
 
   return self
 end
@@ -184,7 +197,11 @@ end
 
 
 function _M:handle_cp_websocket()
-  return self.child:handle_cp_websocket()
+  return self.json_handler:handle_cp_websocket()
+end
+
+function _M:handle_wrpc_websocket()
+  return self.wrpc_handler:handle_cp_websocket()
 end
 
 
@@ -198,7 +215,13 @@ function _M:init_worker()
     return { name = p.name, version = p.handler.VERSION, }
   end, self.plugins_list)
 
-  self.child:init_worker()
+  for _, ch in ipairs{"child", "json_handler", "wrpc_handler"} do
+    local child = self[ch]
+    if child then
+      child:init_worker()
+    end
+  end
+  --self.child:init_worker()
 end