clearCache: Examining and modifying the cache

Description

These are convenience wrappers around DBI package functions. They allow the user a bit of control over what is being cached.

Usage

clearCache(
  x,
  userTags = character(),
  after = NULL,
  before = NULL,
  ask = getOption("reproducible.ask"),
  useCloud = FALSE,
  cloudFolderID = getOption("reproducible.cloudFolderID", NULL),
  drv = getOption("reproducible.drv", RSQLite::SQLite()),
  conn = getOption("reproducible.conn", NULL),
  ...
)
# S4 method for ANY
clearCache(
  x,
  userTags = character(),
  after = NULL,
  before = NULL,
  ask = getOption("reproducible.ask"),
  useCloud = FALSE,
  cloudFolderID = getOption("reproducible.cloudFolderID", NULL),
  drv = getOption("reproducible.drv", RSQLite::SQLite()),
  conn = getOption("reproducible.conn", NULL),
  ...
)
cc(secs, ...)
showCache(
  x,
  userTags = character(),
  after = NULL,
  before = NULL,
  drv = getOption("reproducible.drv", RSQLite::SQLite()),
  conn = getOption("reproducible.conn", NULL),
  ...
)
# S4 method for ANY
showCache(
  x,
  userTags = character(),
  after = NULL,
  before = NULL,
  drv = getOption("reproducible.drv", RSQLite::SQLite()),
  conn = getOption("reproducible.conn", NULL),
  ...
)
keepCache(
  x,
  userTags = character(),
  after = NULL,
  before = NULL,
  ask = getOption("reproducible.ask"),
  drv = getOption("reproducible.drv", RSQLite::SQLite()),
  conn = getOption("reproducible.conn", NULL),
  ...
)
# S4 method for ANY
keepCache(
  x,
  userTags = character(),
  after = NULL,
  before = NULL,
  ask = getOption("reproducible.ask"),
  drv = getOption("reproducible.drv", RSQLite::SQLite()),
  conn = getOption("reproducible.conn", NULL),
  ...
)

Value

Will clear all objects (or those that match userTags, or those between after or before) from the repository located at cachePath of the sim object, if sim is provided, or located in cacheRepo. Invisibly returns a data.table of the removed items.

Arguments

x: A simList or a directory containing a valid Cache repository. Note: For compatibility with Cache argument, cacheRepo can also be used instead of x, though x will take precedence.
userTags: Character vector. If used, this will be used in place of the after and before. Specifying one or more userTag here will clear all objects that match those tags. Matching is via regular expression, meaning partial matches will work unless strict beginning (^) and end ($) of string characters are used. Matching will be against any of the 3 columns returned by showCache(), i.e., artifact, tagValue or tagName. Also, length userTags > 1, then matching is by `and`. For `or` matching, use | in a single character string. See examples.
after: A time (POSIX, character understandable by data.table). Objects cached after this time will be shown or deleted.
before: A time (POSIX, character understandable by data.table). Objects cached before this time will be shown or deleted.
ask: Logical. If FALSE, then it will not ask to confirm deletions using clearCache or keepCache. Default is TRUE
useCloud: Logical. If TRUE, then every object that is deleted locally will also be deleted in the cloudFolderID, if it is non-NULL
cloudFolderID: A googledrive dribble of a folder, e.g., using drive_mkdir(). If left as NULL, the function will create a cloud folder with name from last two folder levels of the cacheRepo path, : paste0(basename(dirname(cacheRepo)), "_", basename(cacheRepo)). This cloudFolderID will be added to options("reproducible.cloudFolderID"), but this will not persist across sessions. If this is a character string, it will treat this as a folder name to create or use on GoogleDrive.
drv: an object that inherits from DBIDriver, or an existing DBIConnection object (in order to clone an existing connection).
conn: A DBIConnection object, as returned by dbConnect().
...: Other arguments. Currently, regexp, a logical, can be provided. This must be TRUE if the use is passing a regular expression. Otherwise, userTags will need to be exact matches. Default is missing, which is the same as TRUE. If there are errors due to regular expression problem, try FALSE. For cc, it is passed to clearCache, e.g., ask, userTags
secs: Currently 3 options: the number of seconds to pass to clearCache(after = secs), a POSIXct time e.g., from Sys.time(), or missing. If missing, the default, then it will delete the most recent entry in the Cache.

Details

If neither after or before are provided, nor userTags, then all objects will be removed. If both after and before are specified, then all objects between after and before will be deleted. If userTags is used, this will override after or before.

cc(secs) is just a shortcut for clearCache(repo = Paths$cachePath, after = secs), i.e., to remove any cache entries touched in the last secs seconds.

clearCache: remove items from the cache based on their userTag or times values.
keepCache: remove all cached items except those based on certain userTags or times values.
showCache: display the contents of the cache.

Examples

Run this code

library(raster)

tmpDir <- file.path(tempdir(), "reproducible_examples", "Cache")
try(clearCache(tmpDir, ask = FALSE), silent = TRUE) # just to make sure it is clear

# Basic use
ranNumsA <- Cache(rnorm, 10, 16, cacheRepo = tmpDir)

# All same
ranNumsB <- Cache(rnorm, 10, 16, cacheRepo = tmpDir) # recovers cached copy
ranNumsD <- Cache(quote(rnorm(n = 10, 16)), cacheRepo = tmpDir) # recovers cached copy

# Any minor change makes it different
ranNumsE <- Cache(rnorm, 10, 6, cacheRepo = tmpDir) # different

## Example 1: basic cache use with tags
ranNumsA <- Cache(rnorm, 4, cacheRepo = tmpDir, userTags = "objectName:a")
ranNumsB <- Cache(runif, 4, cacheRepo = tmpDir, userTags = "objectName:b")
ranNumsC <- Cache(runif, 40, cacheRepo = tmpDir, userTags = "objectName:b")

showCache(tmpDir, userTags = c("objectName"))
showCache(tmpDir, userTags = c("^a$")) # regular expression ... "a" exactly

# Fine control of cache elements -- pick out only the large runif object, and remove it
cache1 <- showCache(tmpDir, userTags = c("runif")) # show only cached objects made during runif
toRemove <- cache1[tagKey == "object.size"][as.numeric(tagValue) > 700]$cacheId
clearCache(tmpDir, userTags = toRemove, ask = FALSE)
cacheAfter <- showCache(tmpDir, userTags = c("runif")) # Only the small one is left

tmpDir <- file.path(tempdir(), "reproducible_examples", "Cache")
try(clearCache(tmpDir, ask = FALSE), silent = TRUE) # just to make sure it is clear

Cache(rnorm, 1, cacheRepo = tmpDir)
thisTime <- Sys.time()
Cache(rnorm, 2, cacheRepo = tmpDir)
Cache(rnorm, 3, cacheRepo = tmpDir)
Cache(rnorm, 4, cacheRepo = tmpDir)
showCache(x = tmpDir) # shows all 4 entries
cc(ask = FALSE, x = tmpDir)
showCache(x = tmpDir) # most recent is gone
cc(thisTime, ask = FALSE, x = tmpDir)
showCache(x = tmpDir) # all those after thisTime gone, i.e., only 1 left
cc(ask = FALSE, x = tmpDir) # Cache is
cc(ask = FALSE, x = tmpDir) # Cache is already empty

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