badge(cran): Implement CRAN service (#479)

* feat: implement CRAN service

* feat(cran): add dependents badge

* fix(cran): alter version badge label

api/cran.ts

@@ -0,0 +1,115 @@
+import got from '../libs/got'
+import { millify, version, versionColor } from '../libs/utils'
+import { createBadgenHandler, PathArgs } from '../libs/create-badgen-handler'
+
+const CRAN_API_URL = 'https://crandb.r-pkg.org/'
+const CRANLOGS_API_URL = 'https://cranlogs.r-pkg.org/'
+
+export default createBadgenHandler({
+  title: 'CRAN',
+  examples: {
+    '/cran/v/dplyr': 'version',
+    '/cran/license/ggplot2': 'license',
+    '/cran/r/data.table': 'r version',
+    '/cran/dependents/R6': 'dependents',
+    '/cran/dt/Rcpp': 'total downloads',
+    '/cran/dd/Rcpp': 'daily downloads',
+    '/cran/dw/Rcpp': 'weekly downloads',
+    '/cran/dm/Rcpp': 'monthly downloads'
+  },
+  handlers: {
+    '/cran/:topic<v|version|license|r|dependents>/:pkg': cranHandler,
+    '/cran/:topic<dd|dw|dm|dt>/:pkg': cranlogsHandler
+  }
+})
+
+async function cranHandler ({ topic, pkg }: PathArgs) {
+  const client = got.extend({ prefixUrl: CRAN_API_URL })
+
+  switch (topic) {
+    case 'v':
+    case 'version': {
+      const data = await client.get(pkg).json<any>()
+      return {
+        subject: 'cran',
+        status: version(data.Version),
+        color: versionColor(data.Version)
+      }
+    }
+    case 'license': {
+      const data = await client.get(pkg).json<any>()
+      const license = data.License?.replace(/\s*\S\s+file\s+LICEN[CS]E$/i, '')
+      return {
+        subject: 'license',
+        status: license || 'unknown',
+        color: 'blue'
+      }
+    }
+    case 'r': {
+      const data = await client.get(pkg).json<any>()
+      const rVersion = data.Depends?.R?.replace(/([<>=]+)\s+/, '$1') || '*'
+      return {
+        subject: 'R',
+        status: version(rVersion),
+        color: versionColor(rVersion)
+      }
+    }
+    case 'dependents': {
+      const data = await client.get(`/-/revdeps/${pkg}`).json<any>()
+      const dependents = Object.keys(data[pkg].Depends).length
+      return {
+        subject: 'dependents',
+        status: millify(dependents),
+        color: 'green'
+      }
+    }
+  }
+}
+
+async function cranlogsHandler ({ topic, pkg }: PathArgs) {
+  switch (topic) {
+    case 'dt': {
+      const downloads = await fetchDownloads(pkg, 'total')
+      return {
+        subject: 'downloads',
+        status: millify(downloads),
+        color: 'green'
+      }
+    }
+    case 'dd': {
+      const downloads = await fetchDownloads(pkg, 'last-day')
+      return {
+        subject: 'downloads',
+        status: `${millify(downloads)}/day`,
+        color: 'green'
+      }
+    }
+    case 'dw': {
+      const downloads = await fetchDownloads(pkg, 'last-week')
+      return {
+        subject: 'downloads',
+        status: `${millify(downloads)}/week`,
+        color: 'green'
+      }
+    }
+    case 'dm': {
+      const downloads = await fetchDownloads(pkg, 'last-month')
+      return {
+        subject: 'downloads',
+        status: `${millify(downloads)}/month`,
+        color: 'green'
+      }
+    }
+  }
+}
+
+async function fetchDownloads (pkg: string, period: string) {
+  const client = got.extend({ prefixUrl: CRANLOGS_API_URL })
+  if (period === 'total') {
+    const [start] = new Date(0).toISOString().split('T')
+    const end = 'last-day'
+    period = [start, end].join(':')
+  }
+  const [stats] = await client.get(`downloads/total/${period}/${pkg}`).json()
+  return stats.downloads
+}

libs/badge-list.ts

@@ -31,6 +31,7 @@ export const liveBadgeList = [
   'haxelib',
   'opam',
   'cpan',
+  'cran',
   'ctan',
   'elm-package',
   'scoop',