Merge pull request #154 from shikokuchuo/daemons

Allow control over whether to reset daemons settings

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: mirai
 Type: Package
 Title: Minimalist Async Evaluation Framework for R
-Version: 1.2.0.9015
+Version: 1.2.0.9016
 Description: Designed for simplicity, a 'mirai' evaluates an R expression
     asynchronously in a parallel process, locally or distributed over the
     network, with the result automatically available upon completion. Modern

NEWS.md

@@ -1,6 +1,9 @@
-# mirai 1.2.0.9015 (development)
+# mirai 1.2.0.9016 (development)
 
 * `daemons(dispatcher = NA)` now provides access to threaded dispatcher (experimental). This implements dispatcher using a thread rather than an external process and is faster and more efficient.
+* `daemons()` behavioural changes:
+  - Return value is now always an integer value - either the number of daemons set if using dispatcher, or the number of daemons launched locally (zero if using a remote launcher).
+  - Gains argument 'force' to control whether calls to `daemons()` resets previous settings for the same compute profile.
 * `mirai_map()` behavioural changes:
   - Combining multiple collection options becomes easier, allowing for instance `x[.stop, .progress]`.
   - Adds `mirai_map()[.progress_cli]` as an alternative progress indicator, using the 'cli' package to show % complete and ETA.

R/daemons.R

@@ -48,6 +48,10 @@
 #'     dispatcher and \sQuote{asyncdial}, \sQuote{autoexit}, \sQuote{cleanup},
 #'     \sQuote{output}, \sQuote{maxtasks}, \sQuote{idletime}, \sQuote{walltime}
 #'     and \sQuote{timerstart} at daemon.
+#' @param force [default TRUE] logical value whether to always reset and apply
+#'     new daemons settings, even if the compute profile is already set up. If
+#'     FALSE, to apply new daemons settings requires daemons to be explicitly
+#'     reset first using \code{daemons(0)}.
 #' @param seed [default NULL] (optional) supply a random seed (single value,
 #'     interpreted as an integer). This is used to inititalise the L'Ecuyer-CMRG
 #'     RNG streams sent to each daemon. Note that reproducible results can be
@@ -64,13 +68,9 @@
 #'     vector comprising [i] the TLS certificate (optionally certificate chain)
 #'     and [ii] the associated private key.
 #'
-#' @return Depending on the arguments supplied:
-#'
-#'     \itemize{
-#'     \item using dispatcher: integer number of daemons set.
-#'     \item or else launching local daemons: integer number of daemons launched.
-#'     \item otherwise: the character host URL.
-#'     }
+#' @return If using dispatcher, the integer number of daemons set, or else the
+#'     integer number of daemons launched locally (zero if using a remote
+#'     launcher).
 #'
 #' @details Use \code{daemons(0)} to reset daemon connections:
 #'     \itemize{
@@ -80,8 +80,8 @@
 #'     \item Any unresolved \sQuote{mirai} will return an \sQuote{errorValue} 19
 #'     (Connection reset) after a reset.
 #'     \item Calling \code{daemons} with revised (or even the same) settings for
-#'     the same compute profile implicitly resets daemons before applying the
-#'     new settings.
+#'     the same compute profile resets daemons before applying the new settings
+#'     if \code{force = TRUE}.
 #'     }
 #'
 #'     If the host session ends, all connected dispatcher and daemon processes
@@ -284,7 +284,7 @@
 #'
 #' @export
 #'
-daemons <- function(n, url = NULL, remote = NULL, dispatcher = TRUE, ...,
+daemons <- function(n, url = NULL, remote = NULL, dispatcher = TRUE, ..., force = TRUE,
                     seed = NULL, tls = NULL, pass = NULL, .compute = "default") {
 
   missing(n) && missing(url) && return(status(.compute))
@@ -373,7 +373,7 @@ daemons <- function(n, url = NULL, remote = NULL, dispatcher = TRUE, ...,
         `[[<-`(envir, "urls", urld)
       }
       `[[<-`(.., .compute, `[[<-`(`[[<-`(envir, "sock", sock), "n", n))
-    } else {
+    } else if (force) {
       daemons(n = 0L, .compute = .compute)
       return(daemons(n = n, url = url, remote = remote, dispatcher = dispatcher, ...,
                      seed = seed, tls = tls, pass = pass, .compute = .compute))
@@ -382,7 +382,7 @@ daemons <- function(n, url = NULL, remote = NULL, dispatcher = TRUE, ...,
   }
 
   is.null(envir) && return(0L)
-  `class<-`(if (envir[["n"]]) envir[["n"]] else envir[["urls"]], c("miraiDaemons", .compute))
+  `class<-`(envir[["n"]], c("miraiDaemons", .compute))
 
 }
 

tests/tests.R

@@ -104,15 +104,17 @@ connection && {
 # additional daemons tests
 connection && .Platform[["OS.type"]] != "windows" && {
   Sys.sleep(1L)
-  nanotest(daemons(url = value <- local_url(), dispatcher = FALSE) == value)
-  nanotesti(status()$daemons, nextget("urls"))
+  nanotestz(daemons(url = value <- local_url(), dispatcher = FALSE))
+  nanotesti(status()$daemons, value)
+  nanotesti(nextget("urls"), value)
   nanotestz(daemons(0L))
   Sys.sleep(1L)
   nanotest(is.character(launch_remote("ws://[::1]:5555", remote = remote_config(command = "echo", args = list(c("Test out:", ".", ">/dev/null")), rscript = "/usr/lib/R/bin/Rscript"))))
   nanotest(is.character(launch_remote("tcp://localhost:5555", remote = ssh_config(remotes = c("ssh://remotehost", "ssh://remotenode"), tunnel = TRUE, command = "echo"))))
   nanotestn(launch_local(local_url(), .compute = "test"))
   Sys.sleep(1L)
-  nanotest(daemons(n = 2L, url = value <- "ws://:0", dispatcher = FALSE, remote = remote_config(quote = TRUE)) != value)
+  nanotestz(daemons(n = 2L, url = value <- "ws://:0", dispatcher = FALSE, remote = remote_config(quote = TRUE)))
+  nanotest(status()$daemons != value)
   nanotestz(daemons(0L))
   Sys.sleep(1L)
   m <- with(daemons(1, dispatcher = FALSE, .compute = "ml"), {