[dev] how to read client body data

[Igor Sysoev]

On Tue, Aug 21, 2007 at 10:51:18PM +0200, Manlio Perillo wrote:

> I'm tryng to understand how to read client body data for a request.
> 
> Reading the perl module and the dav module I have found these options:
> 
> request_body_in_single_buf

An request body may be read in two buffers, first part in
client_header_buffer_size and second part in other memory or file buffer.
This option require to store body in single buffer - memory or file.

> request_body_in_file_only

An body should be store in file only. Even if has zero size.

> request_body_in_persistent_file

An request body temporary file is not removed just after opening.
Use it if you need to temporary file name later.

> request_body_in_clean_file

If request body file still exists on the end of request processing,
then nginx will deletes it by itself.

> request_body_file_group_access

If set temporary file will have 0660 access rights, otherwise - 0600.

> request_body_file_log_level

The log level of warning "a client request body is buffered to a temporary
file". Can be 0 (no log), or NGX_LOG_WARN, NGX_LOG_NOTICE, etc.

> What's the meaning of these parameters?
> 
> 
> To read the client body data, all I have to do is to set the previous 
> parameters (as I wish) and call ngx_http_read_client_request_body with a 
> "secondary" handler that will receive the request object filled with the 
> necessary data?
> 
> Ihis operation is asyncronous, right?
> This is the reason why you need to call ngx_http_finalize_request from 
> the "secondary" handler.

Yes.

> In the end, all I need is:
> 1) if the request body length is <= client_body_buffer_size, store
>    the body in *only one* memory buffer (that is, all the data stored in
>    a contiguos memory block)
>
> 2) if the request body length is > client_body_buffer_size, store
>    *all the* body in a temporary file.
> 
> 
> Is 1) possible?

Yes, use

    r->request_body_in_single_buf = 1;
    r->request_body_in_persistent_file = 1;
    r->request_body_in_clean_file = 1;
    r->request_body_file_log_level = 0;

and you will get it.


-- 
Igor Sysoev
http://sysoev.ru/en/