Hello! On Thu, Sep 29, 2022 at 04:47:43PM -0700, Dk Jack wrote:
> Hi, > In my module I have a body filter. In the body filter, I respond with a 4XX > if the body contains a matching pattern. This is working correctly. > > However, I would like to send a custom response message when the above > situation occurs. I tried doing this by attaching a buffer to the output > headers and calling send header before returning from the filter handler as > shown below. > > ----------------------------------------------------------------------- > r->err_status = http_status; > r->headers_out.status = http_status; > r->headers_out.content_length_n = buf->last - buf->pos; > ngx_str_set(&r->headers_out.content_type, "text/plain"); > > rc = ngx_http_send_header(r); > ----------------------------------------------------------------------- > > However, this causes the "header already sent" error to be raised in the > error.log. The reason for this is because, ngx_http_core_content_phase > calls ngx_http_finalize_request after returning from the body filter. > > ngx_http_finalize_request calls ngx_http_special_response_handler if the > body filter returns any codes greater than NGX_HTTP_SPECIAL_RESPONSE. The > ngx_http_special_response_handler in turn calls > ngx_http_send_special_response which again tries to send the response > header using the stock error message in the ngx_http_error_pages array for > the return code in question. The alert is raised since we already sent it. > > Is there a way to prevent the special_response handler from either sending > this message again or use the buffer attached to the request in the body > filter? It is not possible to return a response body from a request body filter, you can only return an error code. If you want to return a custom response, consider configuring an error_page and return an appropriate custom response message from there. -- Maxim Dounin http://mdounin.ru/ _______________________________________________ nginx-devel mailing list -- nginx-devel@nginx.org To unsubscribe send an email to nginx-devel-le...@nginx.org
