cowboy_req:inform(3)

Name

cowboy_req:inform - Send an informational response

Description

inform(Status, Req :: cowboy_req:req())
    -> inform(StatusCode, #{}, Req)

inform(Status, Headers, Req :: cowboy_req:req())
    -> ok

Status  :: cowboy:http_status()
Headers :: cowboy:http_headers()

Send an informational response.

Informational responses use a status code between 100 and 199. They cannot include a body. This function will not use any of the previously set headers. All headers to be sent must be given directly.

Any number of informational responses can be sent as long as they are sent before the proper response. Attempting to use this function after sending a normal response will result in an error.

The header names must be given as lowercase binary strings. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

Arguments

Status

The status code for the response.

Headers

The response headers.

Header names must be given as lowercase binary strings.

Req

The Req object.

Return value

The atom ok is always returned. It can be safely ignored.

Changelog

• 2.1: Function introduced.

Examples

Req = cowboy_req:inform(102, Req0).

Req = cowboy_req:inform(103, #{
    <<"link">> => <<"</style.css>; rel=preload; as=style">>,
    <<"link">> => <<"</script.js>; rel=preload; as=script">>
}, Req0).

See also

cowboy_req(3), cowboy_req:reply(3), cowboy_req:stream_reply(3), cowboy_req:push(3)