CRAN R Package Scraper

Scrape R package metadata from the CRAN (Comprehensive R Archive Network) database. Extract package titles, descriptions, authors, license info, dependencies, and more from crandb.r-pkg.org — no API key required.

What does it do?

• Search packages by name or keyword — find all packages matching "ggplot", "tidyverse", etc.
• Fetch by name — retrieve full metadata for specific known packages
• List recent releases — monitor the latest packages added to CRAN

Input

Field	Type	Description
mode	select	searchPackages, getByName, or listRecent
searchQuery	string	Keyword to filter packages (for searchPackages mode)
packageNames	array	Exact package names to fetch (for getByName mode)
maxItems	integer	Max results (1–1000, default 50)

Example inputs

Search for ggplot-related packages:

{
  "mode": "searchPackages",
  "searchQuery": "ggplot",
  "maxItems": 20
}

Fetch specific packages:

{
  "mode": "getByName",
  "packageNames": ["ggplot2", "dplyr", "tidyr", "purrr"],
  "maxItems": 10
}

List 30 recent releases:

{
  "mode": "listRecent",
  "maxItems": 30
}

Output

Each record contains:

Field	Description
packageName	CRAN package name
title	Short human-readable title
description	Full package description
version	Latest version string
author	Package author(s)
maintainer	Current maintainer with email
license	License type (e.g. MIT, GPL-2)
url	Package homepage
bugReports	Issue tracker URL
depends	Required package dependencies (list)
imports	Imported packages (list)
suggests	Suggested packages (list)
publishedDate	Publication date
cranUrl	CRAN package page URL
sourceUrl	Same as cranUrl
recordType	Always "package"
scrapedAt	ISO 8601 timestamp

Example output record

{
  "packageName": "ggplot2",
  "title": "Create Elegant Data Visualisations Using the Grammar of Graphics",
  "description": "A system for declaratively creating graphics...",
  "version": "3.5.1",
  "author": "Hadley Wickham [aut], ...",
  "maintainer": "Thomas Lin Pedersen <thomas.pedersen@posit.co>",
  "license": "MIT + file LICENSE",
  "url": "https://ggplot2.tidyverse.org",
  "bugReports": "https://github.com/tidyverse/ggplot2/issues",
  "depends": ["R"],
  "imports": ["cli", "glue", "gtable", "rlang", "scales"],
  "publishedDate": "2024-04-23 08:30:00 UTC",
  "cranUrl": "https://cran.r-project.org/package=ggplot2",
  "sourceUrl": "https://cran.r-project.org/package=ggplot2",
  "recordType": "package",
  "scrapedAt": "2025-01-01T00:00:00+00:00"
}

FAQs

Do I need an API key? No. The CRAN database at crandb.r-pkg.org is a public API with no authentication required.

Is there a rate limit? The actor uses concurrent fetching with a built-in concurrency limit to be respectful of the API.

How many packages are on CRAN? CRAN hosts over 20,000 R packages. The searchPackages mode filters these by name/description to find relevant ones.

Why does searchPackages search by name? Client-side filtering of package names is fast and reliable. The /-/desc endpoint is used when available for broader description-based search.

Can I get all packages? Use listRecent with maxItems=1000 to get the most recently published packages.