Implements event-driven promises capability through the aio callback mechanism

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: nanonext
 Type: Package
 Title: NNG (Nanomsg Next Gen) Lightweight Messaging Library
-Version: 0.13.6.9000
+Version: 0.13.6.9002
 Description: R binding for NNG (Nanomsg Next Gen), a successor to ZeroMQ. NNG is
     a socket library implementing 'Scalability Protocols', a reliable,
     high-performance standard for common communications patterns including
@@ -26,10 +26,14 @@ License: GPL (>= 3)
 BugReports: https://github.com/shikokuchuo/nanonext/issues
 URL: https://shikokuchuo.net/nanonext/, https://github.com/shikokuchuo/nanonext/
 Encoding: UTF-8
-SystemRequirements: 'libnng' >= 1.5 and 'libmbedtls' >= 2.5, or 'cmake' to
+SystemRequirements: 'libnng' >= 1.6 and 'libmbedtls' >= 2.5, or 'cmake' to
     compile NNG and/or Mbed TLS included in package sources
 Depends: 
     R (>= 3.5)
+Imports:
+    later
+LinkingTo: 
+    later
 Suggests: 
     knitr,
     markdown

NAMESPACE

@@ -75,6 +75,7 @@ export(recv_aio)
 export(recv_aio_signal)
 export(reply)
 export(request)
+export(request2)
 export(request_signal)
 export(send)
 export(send_aio)
@@ -96,6 +97,7 @@ export(until_)
 export(wait)
 export(wait_)
 export(write_cert)
+importFrom(later,later)
 importFrom(stats,start)
 importFrom(tools,md5sum)
 importFrom(utils,.DollarNames)

NEWS.md

@@ -1,4 +1,13 @@
-# nanonext 0.13.6 (development)
+# nanonext 0.13.6.9002 (development)
+
+#### New Features
+
+* Integrates with the `later` package to provide the foundation for truly event-driven (non-polling) promises (thanks @jcheng5 for the initial prototype in #28), where side-effects are enacted asynchronously upon aio completion.
+* Adds `request2()` for creating a request that may be turned into an event-driven promise.
+
+#### Updates
+
+* Updates minimum 'libnng' version requirement to v1.6.0 (if a suitable system-installed version is not found, the bundled version is compiled from source).
 
 # nanonext 0.13.6
 

R/context.R

@@ -269,3 +269,21 @@ request_signal <- function(context,
                                          "integer", "logical", "numeric", "raw", "string"),
                            timeout = NULL)
   data <- .Call(rnng_request_signal, context, data, cv, send_mode, recv_mode, timeout, environment())
+
+#' Request2 (RPC Client for Req/Rep Protocol)
+#'
+#' \strong{request2} is the next generation request function that optionally
+#'     takes a condition variable for signalling, and supports event-driven
+#'     promises.
+#'
+#' @rdname request
+#' @export
+#'
+request2 <- function(context,
+                     data,
+                     cv = NULL,
+                     send_mode = c("serial", "raw", "next"),
+                     recv_mode = c("serial", "character", "complex", "double",
+                                   "integer", "logical", "numeric", "raw", "string"),
+                     timeout = NULL)
+  data <- .Call(rnng_request_promise, context, data, cv, send_mode, recv_mode, timeout, environment())

R/nanonext-package.R

@@ -92,6 +92,7 @@
 #' @author Charlie Gao \email{charlie.gao@@shikokuchuo.net}
 #'     (\href{https://orcid.org/0000-0002-0750-061X}{ORCID})
 #'
+#' @importFrom later later
 #' @importFrom stats start
 #' @importFrom tools md5sum
 #' @importFrom utils .DollarNames

README.Rmd

@@ -149,7 +149,7 @@ vignette("nanonext", package = "nanonext")
 
 #### Linux / Mac / Solaris
 
-Installation from source requires 'libnng' >= v1.5.0 and 'libmbedtls' >= 2.5.0 (suitable installations are automatically detected), or else 'cmake' to compile 'libnng' v1.7.3 and 'libmbedtls' v3.6.0 LTS included within the package sources.
+Installation from source requires 'libnng' >= v1.6.0 and 'libmbedtls' >= 2.5.0 (suitable installations are automatically detected), or else 'cmake' to compile 'libnng' v1.7.3 and 'libmbedtls' v3.6.0 LTS included within the package sources.
 
 **It is recommended for optimal performance and stability to let the package automatically compile bundled versions of 'libmbedtls' and 'libnng' during installation.** To ensure the libraries are compiled from source even if system installations are present, set the `NANONEXT_LIBS` environment variable prior to installation e.g. by `Sys.setenv(NANONEXT_LIBS = 1)`.
 
@@ -169,6 +169,7 @@ We would like to acknowledge in particular:
 
 - [Garrett D'Amore](https://github.com/gdamore), author of the NNG library, for generous advice and for implementing a feature request specifically for a more efficient 'aio' implementation in `nanonext`.
 - The [R Consortium](https://www.r-consortium.org/) for funding the development of the secure TLS capabilities in the package, and [Henrik Bengtsson](https://github.com/HenrikBengtsson) and [Will Landau](https://github.com/wlandau/)'s roles in making this possible.
+- [Joe Cheng](https://github.com/jcheng5/) for prototyping the integration of `nanonext` with `later` to support the next generation of completely event-driven promises in `mirai`.
 - [R Core](https://www.r-project.org/contributors.html) for various auxiliary functions for serialisation and raw / character conversion, which have been adopted by the package.
 - [Luke Tierney](https://github.com/ltierney/) and [Mike Cheng](https://github.com/coolbutuseless) for meticulous documentation of the R serialization mechanism, which led to the package's own implementation of a low-level interface to R serialization.
 - [Jeroen Ooms](https://github.com/jeroen) - for his 'Anticonf (tm)' configure script, on which our original 'configure' was based, although much modified since.

README.md

@@ -178,7 +178,7 @@ vignette("nanonext", package = "nanonext")
 
 #### Linux / Mac / Solaris
 
-Installation from source requires ‘libnng’ \>= v1.5.0 and ‘libmbedtls’
+Installation from source requires ‘libnng’ \>= v1.6.0 and ‘libmbedtls’
 \>= 2.5.0 (suitable installations are automatically detected), or else
 ‘cmake’ to compile ‘libnng’ v1.7.3 and ‘libmbedtls’ v3.6.0 LTS included
 within the package sources.
@@ -221,6 +221,9 @@ We would like to acknowledge in particular:
   development of the secure TLS capabilities in the package, and [Henrik
   Bengtsson](https://github.com/HenrikBengtsson) and [Will
   Landau](https://github.com/wlandau/)’s roles in making this possible.
+- [Joe Cheng](https://github.com/jcheng5/) for prototyping the
+  integration of `nanonext` with `later` to support the next generation
+  of completely event-driven promises in `mirai`.
 - [R Core](https://www.r-project.org/contributors.html) for various
   auxiliary functions for serialisation and raw / character conversion,
   which have been adopted by the package.

configure

@@ -128,7 +128,7 @@ fi
 
 echo "#include <nng/nng.h>
 int main() {
-#if NNG_MAJOR_VERSION < 1 || NNG_MAJOR_VERSION == 1 && NNG_MINOR_VERSION < 5
+#if NNG_MAJOR_VERSION < 1 || NNG_MAJOR_VERSION == 1 && NNG_MINOR_VERSION < 6
     *(void *) 0 = 0;
 #endif
 }" | ${CC} ${NNG_CFLAGS} -xc - -o /dev/null > /dev/null 2>&1
@@ -140,7 +140,7 @@ fi
 
 if [ $? -ne 0 ]
 then
-  echo "No existing 'libnng' >= 1.5 found"
+  echo "No existing 'libnng' >= 1.6 found"
   echo "Detecting 'cmake'..."
   which cmake
   if [ $? -ne 0 ]