tar_timestamp: Get the timestamp(s) of a target.

Description Usage Arguments Details Value See Also Examples

View source: R/tar_timestamp.R

Description

Get the time that a target last ran successfully. If there are multiple artifacts, as with file or URL targets, then multiple time stamps may be returned.

Usage

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tar_timestamp(
  name = NULL,
  format = NULL,
  tz = NULL,
  parse = NULL,
  store = targets::tar_config_get("store")
)

Arguments

name

Symbol, name of the target. If NULL (default) then tar_timestamp() will attempt to return the timestamp of the target currently running. Must be called inside a target's command or a supporting function in order to work.

format

Deprecated in targets version 0.6.0 (2021-07-21).

tz

Deprecated in targets version 0.6.0 (2021-07-21).

parse

Deprecated in targets version 0.6.0 (2021-07-21).

store

Character of length 1, path to the targets data store. Defaults to tar_config_get("store"), which in turn defaults to _targets/. When you set this argument, the value of tar_config_get("store") is temporarily changed for the current function call. See tar_config_get() and tar_config_set() for details about how to set the data store path persistently for a project.

Details

tar_timestamp() checks the metadata in _targets/meta/meta, not the actual data. Time stamps are recorded only for targets that run commands: just non-branching targets and individual dynamic branches.

Value

If the target is not recorded in the metadata or cannot be parsed correctly, then tar_timestamp() returns a POSIXct object at 1970-01-01 UTC.

See Also

Other time: tar_newer(), tar_older(), tar_timestamp_raw()

Examples

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if (identical(Sys.getenv("TAR_EXAMPLES"), "true")) {
tar_dir({ # tar_dir() runs code from a temporary directory.
tar_script({
  list(tar_target(x, 1))
}, ask = FALSE)
tar_make()
# Get the timestamp.
tar_timestamp(x)
# We can use the timestamp to cancel the target
# if it already ran within the last hour.
# Be sure to set `cue = tar_cue(mode = "always")`
# if you want the target to always check the timestamp.
tar_script({
  list(
  tar_target(
    x,
    tar_cancel((Sys.time() - tar_timestamp()) < 3600),
    cue = tar_cue(mode = "always")
  )
)}, ask = FALSE)
tar_make()
})
}

targets documentation built on July 21, 2021, 5:07 p.m.