feat(protocol): send worker id to broker

### Summary

This is a feature that sends worker info to broker. This feature is needed for
future PRs to implement worker id based broker queues (to replace worker
connection based queues).

lualib/resty/events/protocol.lua

@@ -1,9 +1,14 @@
 local frame = require "resty.events.frame"
+local codec = require "resty.events.codec"
 
 local _recv_frame = frame.recv
 local _send_frame = frame.send
+local encode = codec.encode
+local decode = codec.decode
 
 local ngx = ngx
+local worker_id = ngx.worker.id
+local worker_pid = ngx.worker.pid
 local tcp = ngx.socket.tcp
 local re_match = ngx.re.match
 local req_sock = ngx.req.socket
@@ -83,12 +88,22 @@ function _Server.new()
 
     sock:settimeout(DEFAULT_TIMEOUT)
 
+    local data, err = _recv_frame(sock)
+    if err then
+        return nil, "failed to read worker info from worker: " .. err
+    end
+
+    local info = decode(data)
+    if not info then
+        return nil, "invalid worker info: " .. data
+    end
+
     return setmetatable({
+        info = info,
         sock = sock,
     }, _SERVER_MT)
 end
 
-
 local _Client = {
     is_closed = is_closed,
     is_timeout = is_timeout,
@@ -153,6 +168,14 @@ function _Client:connect(addr)
         end
     end -- subsystem == "http"
 
+    local _, err = _send_frame(sock, encode({
+        id = worker_id() or -1,
+        pid = worker_pid(),
+    }))
+    if err then
+        return nil, "failed to send worker info: " .. err
+    end
+
     return true
 end
 

t/protocol.t

@@ -7,7 +7,7 @@ use Test::Nginx::Socket::Lua;
 
 repeat_each(2);
 
-plan tests => repeat_each() * (blocks() * 9) - 6;
+plan tests => repeat_each() * (blocks() * 9) - 4;
 
 $ENV{TEST_NGINX_HTML_DIR} ||= html_dir();
 
@@ -33,6 +33,7 @@ __DATA__
                 end
 
                 ngx.log(ngx.DEBUG, "Upgrade: ", ngx.var.http_upgrade)
+                ngx.log(ngx.DEBUG, "Worker ID: ", conn.info.id)
 
                 local data, err = conn:recv_frame()
                 if not data or err then
@@ -84,6 +85,7 @@ GET /test
 world
 --- error_log
 Upgrade: Kong-Worker-Events/1
+Worker ID: 0
 srv recv data: hello
 srv send data: world
 cli recv len: 5
@@ -122,5 +124,3 @@ addr is nginx.sock
 [error]
 [crit]
 [alert]
-
-

t/stream-protocol.t

@@ -7,7 +7,7 @@ use Test::Nginx::Socket::Lua;
 
 repeat_each(2);
 
-plan tests => repeat_each() * (blocks() * 9) - 8;
+plan tests => repeat_each() * (blocks() * 9) - 4;
 
 $ENV{TEST_NGINX_HTML_DIR} ||= html_dir();
 
@@ -32,6 +32,7 @@ __DATA__
                     return
                 end
 
+                ngx.log(ngx.DEBUG, "Worker ID: ", conn.info.id)
                 ngx.log(ngx.DEBUG, "stream connect ok")
 
                 local data, err = conn:recv_frame()
@@ -106,6 +107,8 @@ GET /test
 --- response_body
 world
 --- error_log
+Worker ID: 0
+stream connect ok
 srv recv data: hello
 srv send data: world
 cli recv len: 5
@@ -168,5 +171,3 @@ addr is nginx.sock
 [error]
 [crit]
 [alert]
-
-