How to handle NGX_AGAIN returned by ngx_http_read_client_request_body() within handler module?

[CarlWang]

I checked the error.log and found the ngx_http_v8_handler_request called
in the post access phase.
Then how should  the coding structure be?

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,3545,218023#msg-218023