Deal with class for saving to and loading from Cache or Disk

This generic and some methods will do whatever is required to prepare an object for saving to disk (or RAM) via e.g., saveRDS. Some objects (e.g., terra's Spat*) cannot be saved without first wrapping them. Also, file-backed objects are similar.

.wrap(
  obj,
  cachePath,
  preDigest,
  drv = getDrv(getOption("reproducible.drv", NULL)),
  conn = getOption("reproducible.conn", NULL),
  verbose = getOption("reproducible.verbose"),
  outputObjects = NULL,
  ...
)

# S3 method for class 'list'
.wrap(
  obj,
  cachePath,
  preDigest,
  drv = getDrv(getOption("reproducible.drv", NULL)),
  conn = getOption("reproducible.conn", NULL),
  verbose = getOption("reproducible.verbose"),
  outputObjects = NULL,
  ...
)

# S3 method for class 'environment'
.wrap(
  obj,
  cachePath,
  preDigest,
  drv = getDrv(getOption("reproducible.drv", NULL)),
  conn = getOption("reproducible.conn", NULL),
  verbose = getOption("reproducible.verbose"),
  outputObjects = NULL,
  ...
)

# Default S3 method
.wrap(
  obj,
  cachePath,
  preDigest,
  drv = getDrv(getOption("reproducible.drv", NULL)),
  conn = getOption("reproducible.conn", NULL),
  verbose = getOption("reproducible.verbose"),
  ...
)

# Default S3 method
.unwrap(
  obj,
  cachePath,
  cacheId,
  drv = getDrv(getOption("reproducible.drv", NULL)),
  conn = getOption("reproducible.conn", NULL),
  ...
)

.unwrap(
  obj,
  cachePath,
  cacheId,
  drv = getDrv(getOption("reproducible.drv", NULL)),
  conn = getOption("reproducible.conn", NULL),
  ...
)

# S3 method for class 'environment'
.unwrap(
  obj,
  cachePath,
  cacheId,
  drv = getDrv(getOption("reproducible.drv", NULL)),
  conn = getOption("reproducible.conn", NULL),
  ...
)

# S3 method for class 'list'
.unwrap(
  obj,
  cachePath,
  cacheId,
  drv = getDrv(getOption("reproducible.drv", NULL)),
  conn = getOption("reproducible.conn", NULL),
  ...
)

Arguments

obj: Any arbitrary R object.
cachePath: A repository used for storing cached objects. This is optional if Cache is used inside a SpaDES module.
preDigest: The list of preDigest that comes from CacheDigest of an object
drv: if using a database backend, drv must be an object that inherits from DBIDriver e.g., from package RSQLite, e.g., SQLite
conn: an optional DBIConnection object, as returned by dbConnect().
verbose: Numeric, -1 silent (where possible), 0 being very quiet, 1 showing more messaging, 2 being more messaging, etc. Default is 1. Above 3 will output much more information about the internals of Caching, which may help diagnose Caching challenges. Can set globally with an option, e.g., options('reproducible.verbose' = 0) to reduce to minimal
outputObjects: Optional character vector indicating which objects to return. This is only relevant for list, environment (or similar) objects
...: Arguments passed to methods; default does not use anything in ....
cacheId: Used strictly for messaging. This should be the cacheId of the object being recovered.

Value

Returns an object that can be saved to disk e.g., via saveRDS.

Examples

# For SpatExtent
if (requireNamespace("terra")) {
  ex <- terra::ext(c(0, 2, 0, 3))
  exWrapped <- .wrap(ex)
  ex1 <- .unwrap(exWrapped)
}