Module type S.Client

The Client module implements non-pipelined single HTTP client calls. Each call will open a separate Net connection. For best results, the Body that is returned should be consumed in order to close the file descriptor in a timely fashion. It will still be finalized by a GC hook if it is not used up, but this can take some additional time to happen.

type ctx
val call : ?ctx:ctx -> ?headers:Cohttp.Header.t -> ?body:Body.t -> ?chunked:bool -> Cohttp.Code.meth -> Uri.t -> (Cohttp.Response.t * Body.t) Lwt.t

call ?ctx ?headers ?body ?chunked meth uri will resolve the uri to a concrete network endpoint using context ctx. It will then issue an HTTP request with method meth, adding request headers from headers if present. If a body is specified then that will be included with the request, using chunked encoding if chunked is true. The default is to disable chunked encoding for HTTP request bodies for compatibility reasons.

In most cases you should use the more specific helper calls in the interface rather than invoke this function directly. See head, get and post for some examples.

To avoid leaks, the body needs to be consumed, using the functions provided in the Body module and, if not necessary, should be explicitly drained calling Body.drain_body. Leaks are logged as debug messages by the client, these can be enabled activating the debug logging. For example, this can be done as follows in cohttp-lwt-unix

Cohttp_lwt_unix.Debug.activate_debug ();
Logs.set_level (Some Logs.Warning)

Depending on ctx, the library is able to send a simple HTTP request or an encrypted one with a secured protocol (such as TLS). Depending on how conduit is configured, ctx might initiate a secured connection with TLS (using ocaml-tls) or SSL (using ocaml-ssl), on *:443 or on the specified port by the user. If neitehr ocaml-tls or ocaml-ssl are installed on the system, cohttp/conduit tries the usual (*:80) or the specified port by the user in a non-secured way.

val head : ?ctx:ctx -> ?headers:Cohttp.Header.t -> Uri.t -> Cohttp.Response.t Lwt.t
val get : ?ctx:ctx -> ?headers:Cohttp.Header.t -> Uri.t -> (Cohttp.Response.t * Body.t) Lwt.t
val delete : ?ctx:ctx -> ?body:Body.t -> ?chunked:bool -> ?headers:Cohttp.Header.t -> Uri.t -> (Cohttp.Response.t * Body.t) Lwt.t
val post : ?ctx:ctx -> ?body:Body.t -> ?chunked:bool -> ?headers:Cohttp.Header.t -> Uri.t -> (Cohttp.Response.t * Body.t) Lwt.t
val put : ?ctx:ctx -> ?body:Body.t -> ?chunked:bool -> ?headers:Cohttp.Header.t -> Uri.t -> (Cohttp.Response.t * Body.t) Lwt.t
val patch : ?ctx:ctx -> ?body:Body.t -> ?chunked:bool -> ?headers:Cohttp.Header.t -> Uri.t -> (Cohttp.Response.t * Body.t) Lwt.t
val post_form : ?ctx:ctx -> ?headers:Cohttp.Header.t -> params:(string * string list) list -> Uri.t -> (Cohttp.Response.t * Body.t) Lwt.t