CI: gulp task in support of refcache cleanup & some refcache updates (o…

…pen-telemetry#2948)

gulp-src/README.txt

@@ -0,0 +1,3 @@
+# Gulp task files
+
+All files in this directory, except for `helpers.js`, are gulp tasks.

gulp-src/_util.js

@@ -0,0 +1,9 @@
+const yargs = require('yargs/yargs');
+const { hideBin } = require('yargs/helpers');
+
+exports.taskArgs = () =>
+  yargs(hideBin(process.argv).slice(1))
+    .strict()
+    .help('info')
+    // To avoid "task did not complete" errors, prevent help option from exiting
+    .exitProcess(false);

gulp-src/default.js

@@ -0,0 +1,15 @@
+const gulp = require('gulp');
+
+const usage = `
+Usage:
+  npx gulp --tasks # for a list of tasks
+  npx gulp <task> --info for task argument info`;
+
+const usageTask = (done) => {
+  console.log(usage);
+  done();
+};
+
+usageTask.description = 'Display usage instructions';
+
+gulp.task('default', usageTask);

gulp-src/prune.js

@@ -0,0 +1,57 @@
+// cSpell:ignore refcache
+
+const gulp = require('gulp');
+const fs = require('fs').promises;
+const { taskArgs } = require('./_util');
+
+const refcacheFile = 'static/refcache.json';
+const n_default = 25;
+
+// The refcacheFile is a JSON map with each map entry of the form, e.g.:
+//
+// "https://cncf.io": {
+//     "StatusCode": 206,
+//     "LastSeen": "2023-06-29T13:38:47.996793-04:00"
+//   },
+
+// Prune the oldest <n> entries from refcacheFile in a way that avoids
+// reordering entries (makes diffs easier to manage).
+async function pruneTask() {
+  const argv = taskArgs().options({
+    num: {
+      alias: 'n',
+      type: 'number',
+      description: 'Number of oldest refcache entries to drop.',
+      default: n_default,
+    },
+  }).argv;
+
+  const n = argv.num > 0 ? argv.num : n_default;
+
+  if (argv.info) return; // Info was already displayed
+
+  try {
+    const json = await fs.readFile(refcacheFile, 'utf8');
+    const entries = JSON.parse(json);
+
+    // Create a sorted array of URL keys and `LastSeen` dates
+    const sortedUrlsAndDates = Object.keys(entries)
+      .map((url) => [url, entries[url].LastSeen])
+      .sort((a, b) => new Date(a[1]) - new Date(b[1]));
+
+    // Get oldest argv.num keys
+    const oldestKeys = sortedUrlsAndDates.slice(0, n).map((item) => item[0]);
+
+    // Remove oldest entries
+    oldestKeys.forEach((key) => delete entries[key]);
+
+    const prettyJson = JSON.stringify(entries, null, 2) + '\n';
+    await fs.writeFile(refcacheFile, prettyJson, 'utf8');
+  } catch (err) {
+    console.error(err);
+  }
+}
+
+pruneTask.description = `Prune the oldest '--num <n>' entries from ${refcacheFile} file (default ${n_default}).`;
+
+gulp.task('prune', pruneTask);

gulpfile.js

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+const requireDir = require('require-dir');
+
+requireDir('./gulp-src');

package.json

@@ -67,11 +67,13 @@
   "devDependencies": {
     "autoprefixer": "^10.4.14",
     "cspell": "^6.31.1",
+    "gulp": "^4.0.2",
     "hugo-extended": "0.113.0",
     "netlify-cli": "^15.0.1",
     "npm-run-all": "^4.1.5",
     "postcss-cli": "^10.1.0",
     "prettier": "^2.8.4",
+    "require-dir": "^1.2.0",
     "textlint": "^13.1.4",
     "textlint-filter-rule-allowlist": "^4.0.0",
     "textlint-filter-rule-comments": "^1.2.2",