Kill a process running a heartbeat — rrq_heartbeat

Send a kill signal (typically SIGTERM) to terminate a process that is running a heartbeat. This is used by rrq_controller in order to tear down workers, even if they are processing a task. When a heartbeat process is created, in its main loop it will listen for requests to kill via this function and will forward them to the worker. This is primarily useful where workers are on a different physical machine to the controller where tools::pskill() cannot be used.

Usage

rrq_heartbeat_kill(con, key, signal = tools::SIGTERM)

Arguments

con: A hiredis object
key: The heartbeat key
signal: A signal to send (typically tools::SIGTERM for a "polite" shutdown)

Examples

if (redux::redis_available()) {
  rand_str <- function() {
    paste(sample(letters, 20, TRUE), collapse = "")
  }
  # Suppose we have a process that exposes a heartbeat running on
  # this key:
  key <- sprintf("rrq:heartbeat:%s", rand_str())

  # We can send it a SIGTERM signal over redis using:
  con <- redux::hiredis()
  rrq::rrq_heartbeat_kill(con, key, tools::SIGTERM)
}