bugfix: support socket connection pool and fix repeated ssl_handshake().

Author: chenyyyang

.travis.yml

@@ -1,5 +1,5 @@
 sudo: required
-dist: bionic
+dist: focal
 
 os: linux
 

README.markdown

@@ -385,6 +385,44 @@ An optional Lua table can be specified as the last argument to this method to sp
 * `pool`
 
     Specifies a custom name for the connection pool being used. If omitted, then the connection pool name will be generated from the string template `<host>:<port>`.
+* `pool_size`
+
+  specify the size of the connection pool. If omitted and no
+  `backlog` option was provided, no pool will be created. If omitted
+  but `backlog` was provided, the pool will be created with a default
+  size equal to the value of the [lua_socket_pool_size](https://github.com/openresty/lua-nginx-module/tree/master#lua_socket_pool_size)
+  directive.
+  The connection pool holds up to `pool_size` alive connections
+  ready to be reused by subsequent calls to [connect](#client:connect), but
+  note that there is no upper limit to the total number of opened connections
+  outside of the pool. If you need to restrict the total number of opened
+  connections, specify the `backlog` option.
+  When the connection pool would exceed its size limit, the least recently used
+  (kept-alive) connection already in the pool will be closed to make room for
+  the current connection.
+  Note that the cosocket connection pool is per Nginx worker process rather
+  than per Nginx server instance, so the size limit specified here also applies
+  to every single Nginx worker process. Also note that the size of the connection
+  pool cannot be changed once it has been created.
+  This option was first introduced in the `v0.10.14` release.
+
+* `backlog`
+
+  if specified, this module will limit the total number of opened connections
+  for this pool. No more connections than `pool_size` can be opened
+  for this pool at any time. If the connection pool is full, subsequent
+  connect operations will be queued into a queue equal to this option's
+  value (the "backlog" queue).
+  If the number of queued connect operations is equal to `backlog`,
+  subsequent connect operations will fail and return `nil` plus the
+  error string `"too many waiting connect operations"`.
+  The queued connect operations will be resumed once the number of connections
+  in the pool is less than `pool_size`.
+  The queued connect operation will abort once they have been queued for more
+  than `connect_timeout`, controlled by
+  [settimeouts](#client:set_timeout), and will return `nil` plus
+  the error string `"timeout"`.
+  This option was first introduced in the `v0.10.14` release.
 * `ssl_verify`
 
     Specifies whether to perform SSL certificate verification during the

lib/resty/websocket/client.lua

@@ -2,7 +2,7 @@
 
 
 -- FIXME: this library is very rough and is currently just for testing
---        the websocket server.
+--        the websocket client.
 
 
 local wbproto = require "resty.websocket.protocol"
@@ -100,7 +100,7 @@ function _M.connect(self, uri, opts)
     end
 
     local ssl_verify, server_name, headers, proto_header, origin_header
-    local sock_opts = false
+    local sock_opts = {}
     local client_cert, client_priv_key
 
     if opts then
@@ -120,10 +120,17 @@ function _M.connect(self, uri, opts)
             origin_header = "\r\nOrigin: " .. origin
         end
 
-        local pool = opts.pool
-        if pool then
-            sock_opts = { pool = pool }
+        if opts.pool then
+            sock_opts.pool = opts.pool
         end
+        --pool_size specify the size of the connection pool. If omitted and no backlog option was provided, no pool will be created.
+        if opts.pool_size then
+            sock_opts.pool_size = opts.pool_size
+        end
+        if opts.backlog then
+            sock_opts.backlog = opts.backlog
+        end
+
 
         client_cert = opts.client_cert
         client_priv_key = opts.client_priv_key
@@ -149,16 +156,22 @@ function _M.connect(self, uri, opts)
         end
     end
 
-    local ok, err
-    if sock_opts then
-        ok, err = sock:connect(host, port, sock_opts)
-    else
-        ok, err = sock:connect(host, port)
-    end
+    local ok, err = sock:connect(host, port, sock_opts)
     if not ok then
         return nil, "failed to connect: " .. err
     end
 
+    -- check for connections from pool:
+    local reused_count, err = sock:getreusedtimes()
+    if not reused_count then
+        return nil, "failed to get reused times: " .. tostring(err)
+    end
+
+    if reused_count > 0 then
+        -- being a reused connection (must have done handshake)
+        return 1
+    end
+
     if scheme == "wss" then
         if not ssl_support then
             return nil, "ngx_lua 0.9.11+ required for SSL sockets"
@@ -175,17 +188,6 @@ function _M.connect(self, uri, opts)
         end
     end
 
-    -- check for connections from pool:
-
-    local count, err = sock:getreusedtimes()
-    if not count then
-        return nil, "failed to get reused times: " .. err
-    end
-    if count > 0 then
-        -- being a reused connection (must have done handshake)
-        return 1
-    end
-
     local custom_headers
     if headers then
         custom_headers = concat(headers, "\r\n")