The metadata helps determine if the target is up to date or outdated. The metadata of imports is used to compute the metadata of targets.

drake_meta(target, config = drake::read_drake_config())

Arguments

target

Character scalar, name of the target to get metadata.

config

Master internal configuration list produced by drake_config().

Value

A list of metadata on a target. Does not include the file modification time if the target is a file. That piece is provided later in make() by drake:::finish_meta.

Details

Target metadata is computed with drake_meta(), and then drake:::finish_meta() completes the metadata after the target is built. In other words, the output of drake_meta() corresponds to the state of the target immediately before make() builds it. See diagnose() to read the final metadata of a target, including any errors, warnings, and messages in the last build.

See also

diagnose(), dependency_profile(), make()

Examples

# NOT RUN {
test_with_dir("Quarantine side effects.", {
# This example is not really a user-side demonstration.
# It just walks through a dive into the internals.
# Populate your workspace and write 'report.Rmd'.
load_basic_example() # Get the code with drake_example("basic").
# Create the master internal configuration list.
config <- drake_config(my_plan)
# Optionally, compute metadata on 'small',
# including a hash/fingerprint
# of the dependencies. If meta is not supplied,
# drake_build() computes it automatically.
meta <- drake_meta(target = "small", config = config)
# Should not yet include 'small'.
cached()
# Build 'small'.
# Equivalent to just drake_build(target = "small", config = config).
drake_build(target = "small", config = config, meta = meta)
# Should now include 'small'
cached()
readd(small)
})
# }