scopus_quota: Parse 'Scopus' quota and rate-limit headers

In scopusflow: A Reproducible Workflow Layer for 'Scopus' Bibliographic Searches

Parse 'Scopus' quota and rate-limit headers

Description

Elsevier returns the caller's weekly quota and short-term rate-limit status in response headers. scopus_quota() extracts them into a tidy list so a workflow can pause, schedule or report on the remaining allowance.

Usage

scopus_quota(resp)

Arguments

resp	An httr2::response object, typically captured during a request.

Details

The relevant headers are X-RateLimit-Limit, X-RateLimit-Remaining, X-RateLimit-Reset (epoch seconds), X-ELS-Status and Retry-After. When the API raises a quota or rate-limit error, the parsed quota is also attached to the resulting condition, where it is available as cnd$quota.

Value

A list with elements limit, remaining, reset (a POSIXct time at which the rate-limit window resets, or NA), status and retry_after (seconds, or NA). A missing header yields NA.

Examples

# Build a fake response to show the shape of the output (no network used).
resp <- httr2::response(
  status_code = 200,
  headers = list(
    `X-RateLimit-Limit` = "20000",
    `X-RateLimit-Remaining` = "19987",
    `X-RateLimit-Reset` = "1700000000"
  )
)
scopus_quota(resp)

scopusflow documentation built on June 20, 2026, 5:06 p.m.