Merge branch 'main' into patch-1

Author: janiceilene

Procfile

@@ -1 +1,3 @@
 web: NODE_ENV=production node server.js
+
+release: NODE_ENV=production node script/purge-redis-pages.js

content/actions/learn-github-actions/finding-and-customizing-actions.md

@@ -79,7 +79,7 @@ steps:
 
 #### Using branches
 
-Referring to a specific branch means that the action will always use the latest updates on the target branch, but can create problems if those updates include breaking changes. This example targets a branch named `@main`:
+Specifying a target branch for the action means it will always run the version currently on that branch. This approach can create problems if an update to the branch includes breaking changes. This example targets a branch named `@main`:
 
 ```yaml
 steps:

data/release-notes/2-22/0.yml

@@ -5,7 +5,7 @@ sections:
     - heading: GitHub Actions Beta
       notes:
         - |
-          [GitHub Actions](https://github.com/features/actions) is a powerful, flexible solution for CI/CD and workflow automation. GitHub Actions on Enteprise Server includes tools to help you manage the service, including key metrics in the Management Console, audit logs and access controls to help you control the roll out.
+          [GitHub Actions](https://github.com/features/actions) is a powerful, flexible solution for CI/CD and workflow automation. GitHub Actions on Enterprise Server includes tools to help you manage the service, including key metrics in the Management Console, audit logs and access controls to help you control the roll out.
 
           You will need to provide your own [storage](https://docs.github.com/en/enterprise/2.22/admin/github-actions/enabling-github-actions-and-configuring-storage) and runners for GitHub Actions. AWS S3, Azure Blob Storage and MinIO are supported. Please review the [updated minimum requirements for your platform](https://docs.github.com/en/enterprise/2.22/admin/installation/setting-up-a-github-enterprise-server-instance) before you turn on GitHub Actions. To learn more, contact the GitHub Sales team or [sign up for the beta](https://resources.github.com/beta-signup/). {% comment %} https://github.com/github/releases/issues/775 {% endcomment %}
 

script/purge-redis-pages.js

@@ -0,0 +1,122 @@
+#!/usr/bin/env node
+
+// [start-readme]
+//
+// Run this script to manually purge the Redis rendered page cache.
+// This will typically only be run by Heroku during the deployment process,
+// as triggered via our Procfile's "release" phase configuration.
+//
+// [end-readme]
+
+const program = require('commander')
+const Redis = require('ioredis')
+
+const { REDIS_URL, HEROKU_RELEASE_VERSION, HEROKU_PRODUCTION_APP } = process.env
+const isHerokuProd = HEROKU_PRODUCTION_APP === 'true'
+const pageCacheDatabaseNumber = 1
+const keyScanningPattern = HEROKU_RELEASE_VERSION ? '*:rp:*' : 'rp:*'
+const scanSetSize = 250
+
+const startTime = Date.now()
+const expirationDuration = 30 * 60 * 1000 // 30 minutes
+const expirationTimestamp = startTime + expirationDuration // 30 minutes from now
+
+program
+  .description('Purge the Redis rendered page cache')
+  .option('-d, --dry-run', 'print keys to be purged without actually purging')
+  .parse(process.argv)
+
+const dryRun = program.dryRun
+
+// verify environment variables
+if (!REDIS_URL) {
+  if (isHerokuProd) {
+    console.error('Error: you must specify the REDIS_URL environment variable.\n')
+    process.exit(1)
+  } else {
+    console.warn('Warning: you did not specify a REDIS_URL environment variable. Exiting...\n')
+    process.exit(0)
+  }
+}
+
+console.log({
+  HEROKU_RELEASE_VERSION,
+  HEROKU_PRODUCTION_APP
+})
+
+purgeRenderedPageCache()
+
+function purgeRenderedPageCache () {
+  const redisClient = new Redis(REDIS_URL, { db: pageCacheDatabaseNumber })
+  let totalKeyCount = 0
+  let iteration = 0
+
+  // Create a readable stream (object mode) for the SCAN cursor
+  const scanStream = redisClient.scanStream({
+    match: keyScanningPattern,
+    count: scanSetSize
+  })
+
+  scanStream.on('end', function () {
+    console.log(`Done purging keys; affected total: ${totalKeyCount}`)
+    console.log(`Time elapsed: ${Date.now() - startTime} ms`)
+
+    // This seems to be unexpectedly necessary
+    process.exit(0)
+  })
+
+  scanStream.on('error', function (error) {
+    console.error('An unexpected error occurred!\n' + error.stack)
+    console.error('\nAborting...')
+    process.exit(1)
+  })
+
+  scanStream.on('data', async function (keys) {
+    console.log(`[Iteration ${iteration++}] Received ${keys.length} keys...`)
+
+    // NOTE: It is possible for a SCAN cursor iteration to return 0 keys when
+    // using a MATCH because it is applied after the elements are retrieved
+    if (keys.length === 0) return
+
+    if (dryRun) {
+      console.log(`DRY RUN! This iteration might have set TTL for up to ${keys.length} keys:\n - ${keys.join('\n - ')}`)
+      return
+    }
+
+    // Pause the SCAN stream while we set a TTL on these keys
+    scanStream.pause()
+
+    // Find existing TTLs to ensure we aren't extending the TTL if it's already set
+    // PTTL mykey // only operate on -1 result values or those greater than ONE_HOUR_FROM_NOW
+    const pttlPipeline = redisClient.pipeline()
+    keys.forEach(key => pttlPipeline.pttl(key))
+    const pttlResults = await pttlPipeline.exec()
+
+    // Update pertinent keys to have TTLs set
+    let updatingKeyCount = 0
+    const pexpireAtPipeline = redisClient.pipeline()
+    keys.forEach((key, i) => {
+      const [error, pttl] = pttlResults[i]
+      const needsShortenedTtl = error == null && (pttl === -1 || pttl > expirationDuration)
+      const isOldKey = !HEROKU_RELEASE_VERSION || !key.startsWith(`${HEROKU_RELEASE_VERSION}:`)
+
+      if (needsShortenedTtl && isOldKey) {
+        pexpireAtPipeline.pexpireat(key, expirationTimestamp)
+        updatingKeyCount += 1
+      }
+    })
+
+    // Only update TTLs if there are records worth updating
+    if (updatingKeyCount > 0) {
+      // Set all the TTLs
+      const pexpireAtResults = await pexpireAtPipeline.exec()
+      const updatedResults = pexpireAtResults.filter(([error, result]) => error == null && result === 1)
+
+      // Count only the entries whose TTLs were successfully updated
+      totalKeyCount += updatedResults.length
+    }
+
+    // Resume the SCAN stream
+    scanStream.resume()
+  })
+}