Check External Sentinel Staleness for targets

Usage

check_external_sentinel(
  sentinel_path,
  input_files,
  on_missing = c("stop", "warn"),
  on_stale = c("stop", "warn", "delete")
)

Arguments

sentinel_path: Path to sentinel file, either relative to project root or absolute
input_files: Character vector of input file paths, either relative to project root or absolute
on_missing: Action when sentinel missing: "stop" (default) or "warn"
on_stale: Action when sentinel stale: "stop" (default), "warn", or "delete"

Value

Relative path to sentinel (invisibly) if valid, otherwise stops with informative error

Details

All paths are resolved relative to the project root using `here::here()`. Absolute paths are automatically converted to relative paths for comparison with stored paths, ensuring consistency across platforms and working directories.

All timestamps are compared in UTC, ensuring correct staleness detection even when sentinels are shared across machines in different timezones.

Validates sentinel by checking: 1. Sentinel file exists 2. Input files haven't changed since external process ran (compared by file content hash only) 3. All expected input files are tracked in sentinel

If validation fails, provides clear error message and optionally deletes stale sentinel.

Note: Only file hashes are used for staleness checks. Modification times are stored for information only.

Examples

if (FALSE) { # \dontrun{
# Using relative paths (recommended)
check_external_sentinel(
    sentinel_path = ".external/job_complete.json",
    input_files = c("data/raw.csv", "params.json")
)
} # }