HTTP Rest Server

NAMESPACE

@@ -91,6 +91,7 @@ export(request)
 export(send)
 export(send_aio)
 export(serial_config)
+export(server)
 export(set_promise_context)
 export(socket)
 export(stat)

NEWS.md

@@ -4,6 +4,7 @@
 
 * Adds support for threaded dispatcher in `mirai`.
 * Adds 'recvAio' method for `promises::as.promise()` and `promises::is.promising()` to enable 'recvAio' promises.
+* Adds `server()`, an HTTP REST server for evaluation of R expressions (experimental).
 
 #### Updates
 

R/server.R

@@ -0,0 +1,79 @@
+# Copyright (C) 2022-2024 Hibiki AI Limited <[email protected]>
+#
+# This file is part of nanonext.
+#
+# nanonext is free software: you can redistribute it and/or modify it under the
+# terms of the GNU General Public License as published by the Free Software
+# Foundation, either version 3 of the License, or (at your option) any later
+# version.
+#
+# nanonext is distributed in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+# A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# nanonext. If not, see <https://www.gnu.org/licenses/>.
+
+# nanonext - server - HTTP REST Server -----------------------------------------
+
+#' Start REST Server
+#'
+#' Creates an instance of an HTTP REST server which evaluates R expressions sent
+#'     to it [EXPERIMENTAL]. As arbitrary R expressions are evaluated, this
+#'     should only be deployed on the local machine (using the 127.0.0.1
+#'     loopback address) in a trusted environment.
+#'
+#' @param url full http address including hostname, port and path at which to
+#'     host the server.
+#'
+#' @details Query the API with an HTTP client using the \sQuote{POST} method,
+#'     with the request data being the R expression as a text string. The
+#'     received response body will consist of the evaluation result as a text
+#'     string (if of the appropriate type), or otherwise a serialized R object,
+#'     which should be passed to \code{\link{unserialize}}.
+#'
+#'     If the expression could not be parsed or evaluated, the response will be
+#'     returned with a status code of 500 and a blank body.
+#'
+#'     User interrupts will only be processed after the next query has been
+#'     completed, hence return from the function may not be immediate. Use
+#'     \sQuote{ctrl + \\} to forcibly quit the entire R session if required.
+#'
+#' @return This function never returns.
+#'
+#' @examples
+#' if (interactive()) {
+#'
+#' # run server in a new session:
+#' # Rscript -e 'nanonext::server("http://127.0.0.1:5555/api/rest")'
+#'
+#' # query using curl:
+#' # curl -X POST http://127.0.0.1:5555/api/rest -d 'format(Sys.time())'
+#'
+#' ncurl(
+#'   "http://127.0.0.1:5555/api/rest",
+#'   method = "POST",
+#'   data = "format(Sys.time())"
+#' )
+#'
+#' # error will return status of 500
+#' ncurl(
+#'   "http://127.0.0.1:5555/api/rest",
+#'   method = "POST",
+#'   data = "not_valid()"
+#' )
+#'
+#' res <- ncurl(
+#'   "http://127.0.0.1:5555/api/rest",
+#'   convert = FALSE,
+#'   method = "POST",
+#'   data = "data.frame(random = nanonext::random(3))"
+#' )
+#' if (!is_error_value(res$data)) unserialize(res$data)
+#'
+#' }
+#'
+#' @export
+#'
+server <- function(url = "http://127.0.0.1:5555/api/rest")
+  .Call(rnng_rest_server, url)

src/init.c

@@ -167,6 +167,7 @@ static const R_CallMethodDef callMethods[] = {
   {"rnng_recv", (DL_FUNC) &rnng_recv, 4},
   {"rnng_recv_aio", (DL_FUNC) &rnng_recv_aio, 6},
   {"rnng_request", (DL_FUNC) &rnng_request, 7},
+  {"rnng_rest_server", (DL_FUNC) &rnng_rest_server, 1},
   {"rnng_send", (DL_FUNC) &rnng_send, 4},
   {"rnng_send_aio", (DL_FUNC) &rnng_send_aio, 5},
   {"rnng_serial_config", (DL_FUNC) &rnng_serial_config, 4},

src/nanonext.h

@@ -294,6 +294,7 @@ int nano_matchargs(const SEXP);
 
 void pipe_cb_signal(nng_pipe, nng_pipe_ev, void *);
 void tls_finalizer(SEXP);
+void nano_printf(const int, const char *, ...);
 
 SEXP rnng_advance_rng_state(void);
 SEXP rnng_aio_call(SEXP);
@@ -347,6 +348,7 @@ SEXP rnng_reap(SEXP);
 SEXP rnng_recv(SEXP, SEXP, SEXP, SEXP);
 SEXP rnng_recv_aio(SEXP, SEXP, SEXP, SEXP, SEXP, SEXP);
 SEXP rnng_request(SEXP, SEXP, SEXP, SEXP, SEXP, SEXP, SEXP);
+SEXP rnng_rest_server(SEXP);
 SEXP rnng_send(SEXP, SEXP, SEXP, SEXP);
 SEXP rnng_send_aio(SEXP, SEXP, SEXP, SEXP, SEXP);
 SEXP rnng_serial_config(SEXP, SEXP, SEXP, SEXP);