simplifies status()

DESCRIPTION

@@ -21,7 +21,7 @@ BugReports: https://github.com/shikokuchuo/mirai/issues
 URL: https://shikokuchuo.net/mirai/, https://github.com/shikokuchuo/mirai/
 Encoding: UTF-8
 Depends: 
-    R (>= 2.12)
+    R (>= 3.5)
 Imports: 
     nanonext (>= 0.9.1)
 RoxygenNote: 7.2.3

NEWS.md

@@ -4,8 +4,11 @@
   + Straight pass through without serialization/unserialization allows higher performance and lower memory utilisation.
   + Fixes edge cases of `status()` occasionally failing to communicate with dispatcher.
 * `saisei()` with argument `force = TRUE` now immediately regenerates the socket and returns any ongoing mirai as an 'errorValue'. This allows tasks that consistently hang or crash to be cancelled rather than being repeated when a new daemon connects.
-* `status()` now returns the daemons status matrix with the column 'i' for ease of use with other functions such as `saisei()` or `launch_local()` etc. that require this.
-* Error messages tweaked to be more accurate and informative.
+* Tweaks to `status():`
+  + The daemons status matrix adds a column 'i' for ease of use with other functions such as `saisei()` or `launch_local()` etc.
+  + `$daemons` now returns NULL if daemons have not been set.
+* Certain error messages are more accurate and informative.
+* Requires nanonext >= [0.9.1], and consequently R >= 3.5.
 
 # mirai 0.9.1
 

R/mirai.R

@@ -866,13 +866,14 @@ saisei <- function(i = 1L, force = FALSE, .compute = "default") {
 #'
 #' @return A named list comprising:
 #'     \itemize{
-#'     \item{\strong{connections}} {- number of active connections. Always 1L
-#'     when using dispatcher as there is a single connection to the dispatcher,
-#'     which in turn connects to the daemons.}
-#'     \item{\strong{daemons}} {- if using dispatcher: a status matrix (see
-#'     Status Matrix section below), or else an integer 'errorValue' if
-#'     communication with dispatcher was unsuccessful. If not using
-#'     dispatcher: the character host URL. If daemons are not set: 0L.}
+#'     \item{\strong{connections}} {- integer number of active connections.
+#'     \cr Using dispatcher: Always 1L as there is a single connection to
+#'     dispatcher, which connects to the daemons in turn.}
+#'     \item{\strong{daemons}} {- of variable type.
+#'     \cr Using dispatcher: a status matrix (see Status Matrix section below),
+#'     or else an integer 'errorValue' if communication with dispatcher failed.
+#'     \cr Not using dispatcher: the character host URL.
+#'     \cr Not set: NULL.}
 #'     }
 #'
 #' @section Status Matrix:
@@ -911,9 +912,9 @@ saisei <- function(i = 1L, force = FALSE, .compute = "default") {
 status <- function(.compute = "default") {
 
     envir <- ..[[.compute]]
-    active <- length(envir[["sock"]])
-    list(connections = if (active) stat(envir[["sock"]], "pipes") else 0L,
-         daemons = if (length(envir[["sockc"]])) query_status(envir) else if (active) envir[["urls"]] else 0L)
+    sock <- envir[["sock"]]
+    list(connections = if (is.null(sock)) 0L else as.integer(stat(sock, "pipes")),
+         daemons = if (is.null(envir[["sockc"]])) envir[["urls"]] else query_status(envir))
 
 }
 

README.Rmd

@@ -280,7 +280,7 @@ The daemons interface may also be used to send tasks for computation to remote d
 
 Call `daemons()` specifying 'url' as a character value the host network address and a port that is able to accept incoming connections.
 
-The examples below use an illustrative local network IP address of '10.216.62.86'.
+The examples below use an illustrative local network IP address of '10.75.34.138'.
 
 A port on the host machine also needs to be open and available for inbound connections from the local network, illustratively '5555' in the examples below.
 
@@ -293,15 +293,15 @@ The default `dispatcher = TRUE` creates a background `dispatcher()` process on t
 It is recommended to use a websocket URL starting `ws://` instead of TCP in this scenario (used interchangeably with `tcp://`). A websocket URL supports a path after the port number, which can be made unique for each daemon. In this way a dispatcher can connect to an arbitrary number of daemons over a single port.
 
 ```{r localqueue}
-daemons(n = 4, url = "ws://10.216.62.86:5555")
+daemons(n = 4, url = "ws://10.75.34.138:5555")
 ```
 
 Above, a single URL was supplied, along with `n = 4` to specify that the dispatcher should listen at 4 URLs. In such a case, an integer sequence is automatically appended to the path `/1` through `/4` to produce these URLs.
 
 Alternatively, supplying a vector of URLs allows the use of arbitrary port numbers / paths, e.g.:
 
 ```{r vectorqueue, eval=FALSE}
-daemons(url = c("ws://10.216.62.86:5566/cpu", "ws://10.216.62.86:5566/gpu", "ws://10.216.62.86:7788/1"))
+daemons(url = c("ws://10.75.34.138:5566/cpu", "ws://10.75.34.138:5566/gpu", "ws://10.75.34.138:7788/1"))
 ```
 
 Above, 'n' is not specified, in which case its value is inferred from the length of the 'url' vector supplied.
@@ -311,10 +311,10 @@ Above, 'n' is not specified, in which case its value is inferred from the length
 On the remote resource, `daemon()` may be called from an R session, or directly from a shell using Rscript. Each daemon instance should dial into one of the unique URLs that the dispatcher is listening at:
 
 ```
-Rscript -e 'mirai::daemon("ws://10.216.62.86:5555/1")'
-Rscript -e 'mirai::daemon("ws://10.216.62.86:5555/2")'
-Rscript -e 'mirai::daemon("ws://10.216.62.86:5555/3")'
-Rscript -e 'mirai::daemon("ws://10.216.62.86:5555/4")'
+Rscript -e 'mirai::daemon("ws://10.75.34.138:5555/1")'
+Rscript -e 'mirai::daemon("ws://10.75.34.138:5555/2")'
+Rscript -e 'mirai::daemon("ws://10.75.34.138:5555/3")'
+Rscript -e 'mirai::daemon("ws://10.75.34.138:5555/4")'
 
 ```
 
@@ -323,7 +323,7 @@ Note that `daemons()` should be set up on the host machine before launching `dae
 `launch_remote()` may also be used to launch daemons directly on a remote machine. For example, if the remote machine at 10.216.62.100 accepts SSH connections over port 22:
 
 ```{r launchremote, eval=FALSE}
-launch_remote(1:4, command = "ssh", args = c("-p 22 10.216.62.100", .))
+launch_remote(1:4, command = "ssh", args = c("-p 22 10.75.34.138", .))
 ```
 ```{r launchremotereal, echo=FALSE}
 launch_remote(1:4)
@@ -362,7 +362,7 @@ Closing the connection causes the dispatcher to exit automatically, and in turn
 By specifying `dispatcher = FALSE`, remote daemons connect directly to the host process. The host listens at a single URL, and distributes tasks to all connected daemons.
 
 ```{r remote, eval=FALSE}
-daemons(url = "tcp://10.216.62.86:0", dispatcher = FALSE)
+daemons(url = "tcp://10.75.34.138:0", dispatcher = FALSE)
 ```
 
 Alternatively, simply supply a colon followed by the port number to listen on all interfaces on the local host, for example:
@@ -378,17 +378,17 @@ Note that above, the port number is specified as zero. This is a wildcard value
 On the network resource, `daemon()` may be called from an R session, or an Rscript invocation from a shell. This sets up a remote daemon process that connects to the host URL and receives tasks:
 
 ```
-Rscript -e 'mirai::daemon("tcp://10.216.62.86:0")'
+Rscript -e 'mirai::daemon("tcp://10.75.34.138:0")'
 ```
 Note that `daemons()` should be set up on the host machine before launching `daemon()` on remote resources, otherwise the daemon instances will exit if a connection is not immediately available. Alternatively, specifying `daemon(asyncdial = TRUE)` will allow daemons to wait (indefinitely) for a connection to become available.
 
-`launch_remote()` may also be used to launch daemons directly on a remote machine. For example, if the remote machine at 10.216.62.100 accepts SSH connections over port 22:
+`launch_remote()` may also be used to launch daemons directly on a remote machine. For example, if the remote machine at 10.75.34.100 accepts SSH connections over port 22:
 
 ```{r launchremoteu, eval=FALSE}
-launch_remote("tcp://10.216.62.86:0", command = "ssh", args = c("-p 22 10.216.62.100", .))
+launch_remote("tcp://10.75.34.138:0", command = "ssh", args = c("-p 22 10.75.34.100", .))
 ```
 ```{r launchremoteureal, echo=FALSE}
-launch_remote("tcp://10.216.62.86:0")
+launch_remote("tcp://10.75.34.138:0")
 ```
 
 The returned vector comprises the shell commands executed on the remote machine.