R/cacheDirectories.R

In databio/simpleCache: Simply Caching R Objects

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# CACHE DIRECTORY FUNCTIONS
################################################################################
# These are exported functions for interacting with global variables that
# specify default directories for 2 cache types: project caches and shared
# caches.

#' Sets a global variable specifying the default cache directory for
#' \code{\link{simpleCache}} calls.
#'
#' @param cacheDir Directory where caches should be stored
#' @export
#' @example
#' R/examples/example.R
setCacheDir = function(cacheDir=NULL) { .setDir("RCACHE.DIR", cacheDir) }

#' Fetcher of the currently set cache directory.
#'
#' \code{getCacheDir} retrieves the value of the option that stores the currently 
#' set cache directory path.
#'
#' @return If the option is set, the path to the currently set cache directory; otherwise, \code{NULL}.
#' @export
getCacheDir = function() { getOption("RCACHE.DIR") }

#' Set shared cache directory
#'
#' Sets global variable specifying the default cache directory for
#' \code{\link{simpleCacheShared}} calls; this function is simply a helper alias for caching
#' results that will be used across projects.
#'
#' @param sharedCacheDir Directory where shared caches should be stored
#' @export
setSharedCacheDir = function(sharedCacheDir=NULL) { .setDir("RESOURCES.RCACHE", sharedCacheDir) }

#' Sets local cache build directory with scripts for building files.
#'
#' @param cacheBuildDir Directory where build scripts are stored.
#' @export
setCacheBuildDir = function(cacheBuildDir=NULL) { .setDir("RBUILD.DIR", cacheBuildDir) }

#' View simpleCache options
#'
#' Views simpleCache global variables
#' @export
simpleCacheOptions = function() {
	message("RESOURCES.RCACHE:\t", getOption("RESOURCES.RCACHE"))
	message("RCACHE.DIR:\t", getCacheDir())
	message("RBUILD.DIR:\t", getOption("RBUILD.DIR"))
	message("SIMPLECACHE.ENV:\t", getOption("SIMPLECACHE.ENV"))
}

#' Add a cache search environment
#'
#' Append a new Environment name (a character string) to a global option
#' which is a vector of such names. SimpleCache will search all of these
#' environments to check if a cache is previously loaded, before reloading it.
#' 
#' @param addEnv Environment to append to the shared cache search list
#' @export
addCacheSearchEnvironment = function(addEnv) {
	options(SIMPLECACHE.ENV=append(addEnv, getOption("SIMPLECACHE.ENV")))
}

#' Sets global option of cache search environments to \code{NULL}.
#' 
#' @export
resetCacheSearchEnvironment = function() {
	options(SIMPLECACHE.ENV=NULL)
}


.setDir = function(optname, dirpath=NULL) {
  diropts = list(ifelse(is.null(dirpath), getwd(), dirpath))
  names(diropts) = optname
  do.call(options, diropts)
}