doc: document pool_only_after_response

Author: GuyLewin

Diff for: README.md

@@ -171,6 +171,7 @@ The options table has the following fields:
 * `pool`: custom connection pool name. Option as per [OpenResty docs](https://github.com/openresty/lua-nginx-module#tcpsockconnect), except that the default will become a pool name constructed using the SSL / proxy properties, which is important for safe connection reuse. When in doubt, leave it blank!
 * `pool_size`: option as per [OpenResty docs](https://github.com/openresty/lua-nginx-module#tcpsockconnect)
 * `backlog`: option as per [OpenResty docs](https://github.com/openresty/lua-nginx-module#tcpsockconnect)
+* `pool_only_after_response`: when enabled, set_keepalive() verifies http response fully read before pooling. Default is `false`
 * `proxy_opts`: sub-table, defaults to the global proxy options set, see [set\_proxy\_options](#set_proxy_options).
 * `ssl_verify`: option as per [OpenResty docs](https://github.com/openresty/lua-nginx-module#tcpsocksslhandshake), except that it defaults to `true`.
 * `ssl_server_name`: option as per [OpenResty docs](https://github.com/openresty/lua-nginx-module#tcpsocksslhandshake)

Diff for: lib/resty/http_connect.lua

@@ -20,7 +20,7 @@ client:connect {
     pool = nil,                       -- connection pool name, leave blank! this function knows best!
     pool_size = nil,                  -- options as per: https://github.com/openresty/lua-nginx-module#tcpsockconnect
     backlog = nil,
-    pool_only_after_response = false, -- only allow set_keepalive() after http response fully read
+    pool_only_after_response = false, -- set_keepalive() verifies http response fully read before pooling
 
     -- ssl options as per: https://github.com/openresty/lua-nginx-module#tcpsocksslhandshake
     ssl_server_name = nil,