Ocamlnet 3 Reference Manual : Netcgi_fcgi

# Module Netcgi_fcgi

    module Netcgi_fcgi: sig .. end

FastCGI connector.

Remark: This connector does not allow requests to be multiplexed (and let it know to the web server via FCGI_MPXS_CONNS=0). Multiplexing requests is seldom done by FastCGI modules and is even sometimes impossible because of bugs in them. Moreover, multiplexing is mostly useful if concurrent requests are handled by different threads while this library use a single thread to process all requests coming on a given connection. If the need is felt (speak out!), a multithreaded connector can be built on the side of this one.

    class type cgi = object .. end

The usual `Netcgi.cgi` class with FCGI specific methods.

    val run : ?config:Netcgi.config ->
           ?allow:(Unix.sockaddr -> bool) ->
           ?output_type:Netcgi.output_type ->
           ?arg_store:Netcgi.arg_store ->
           ?exn_handler:Netcgi.exn_handler ->
           ?sockaddr:Unix.sockaddr -> ?port:int -> (cgi -> unit) -> unit

`run f` register the function `f` as a main function of the script. Each call to the script will execute `f cgi`. The code outside `f` will be executed only once (when the script is loaded into memory) which allows to cache database connections, etc.
`config` : Default: `Netcgi.default_config`
`allow` : Tells whether a connection from the socket is allowed. Default: Use the comma separated list given in the environment variable FCGI_WEB_SERVER_ADDRS or allow all if it does not exist.
`output_type` : Default: ``Direct ""`
`arg_store` : Default: ``Automatic` for all arguments.
`exn_handler` : See `Netcgi.exn_handler`. Default: delegate all exceptions to the default handler.
`sockaddr` : tells on what socket to contact the script. If not specified, the script expects to be launched by the web server and to communicate with it through stdin. For external scripts (launched independently of the web server and possibly on a different machine), set `sockaddr` to the address the web server needs to connect to to talk to the script (this address must also be specified in the wen server config file).
`port` : alternative way to specify `sockaddr` for localhost

Your application should be ready handle SIGUSR1, used to resquest a "graceful" process shutdown, and SIGTERM to request a quick shutdown.

    val handle_request : Netcgi.config ->
           Netcgi.output_type ->
           Netcgi.arg_store ->
           Netcgi.exn_handler ->
           (cgi -> unit) ->
           max_conns:int ->
           log:(string -> unit) option -> Unix.file_descr -> Netcgi.connection_directive

`handle_request config output_type arg_store eh f ~max_conns ~log fd`: This is a lower-level interface that processes exactly one request arriving on the existing connection `fd`.

`max_conns` is passed to the FCGI client and indicates how many connections this server can process in parallel.

`log` is the error logger function or `None`, in which case errors are passed through to the FCGI client.

The other arguments are just like for `run`.

The return value indicates whether the connection can be kept open or must be closed.