Watch a deferred pipeline and log errors incrementally

Polls deferred_errors() and deferred_status() every interval seconds. Only appends new errors to the log (deduplicates via in-memory signature set). Writes a [DONE] summary when all chunks complete.

Usage

parade_watch(d, interval = 30, log_path = "parade.log", max_errors = 20L)

Arguments

d

A parade_deferred object

interval

Polling interval in seconds (default 30)

log_path

Path to log file (default "parade.log"). Set to NULL to disable file logging (still blocks until done).

max_errors

Maximum error lines to write per run (default 20)

Value

The deferred object (invisibly)

Examples

# \donttest{
grid <- data.frame(x = 1:4, group = rep(c("A", "B"), 2))
fl <- flow(grid) |>
  stage("calc", function(x) x^2, schema = returns(result = dbl())) |>
  distribute(dist_local(by = "group"))
d <- submit(fl)
parade_watch(d, interval = 5, log_path = NULL)
# }