purrr: rate-helpers – R documentation

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rate-helpers

Create delaying rate settings

Description

These helpers create rate settings that you can pass to insistently(). You can also use them in your own functions with rate_sleep().

Usage

rate_delay(pause = 1, max_times = Inf)

rate_backoff(
  pause_base = 1,
  pause_cap = 60,
  pause_min = 1,
  max_times = 3,
  jitter = TRUE
)

is_rate(x)

Arguments

`pause`	Delay between attempts in seconds.
`max_times`	Maximum number of requests to attempt.
`pause_base, pause_cap`	`rate_backoff()` uses an exponential back-off so that each request waits `pause_base * 2^i` seconds, up to a maximum of `pause_cap` seconds.
`pause_min`	Minimum time to wait in the backoff; generally only necessary if you need pauses less than one second (which may not be kind to the server, use with caution!).
`jitter`	Whether to introduce a random jitter in the waiting time.
`x`	An object to test.

Examples

# A delay rate waits the same amount of time:
rate <- rate_delay(0.02)
for (i in 1:3) rate_sleep(rate, quiet = FALSE)

# A backoff rate waits exponentially longer each time, with random
# jitter by default:
rate <- rate_backoff(pause_base = 0.2, pause_min = 0.005)
for (i in 1:3) rate_sleep(rate, quiet = FALSE)

purrr

Functional Programming Tools

v0.3.4

GPL-3 | file LICENSE

Authors

Lionel Henry [aut, cre], Hadley Wickham [aut], RStudio [cph, fnd]

Initial release