Purging

Purge cached content to force the CDN to request a new version of that content from an origin server or Serverless Compute. This ensures that the latest version of that content is delivered to your clients.

Purge by relative path, surrogate key, or all cached content using the:

• Edgio Developer console
• Edgio CLI
• Edgio REST API (clear-cache)

Relative Path #

You may specify a relative path that identifies the set of cached respones that will be purged. This relative path starts directly after the hostname.

Example:

This example assumes that you need to purge the following content:

https://cdn.example.com/sports/basketball/marchtournament.html

Purge the above URL by specifying the following relative path:

/sports/basketball/marchtournament.html

Alternatively, you can use an * to recursively purge a directory. The following relative path pattern recursively purges all content from the /sports directory including marchtournament.html:

/sports/*

Surrogate Key #

You may purge cached content by surrogate key (aka cache tag). A surrogate key is a label that you may apply to cached responses. Purging by surrogate key allows you to purge related content across your entire site.

Tagging Cached Content #

Apply a surrogate key by setting the Surrogate-Key response header.

Syntax: Surrogate-Key: <TAG1> <TAG2> <TAG3>

Example:

For example, the following response header applies three surrogate keys to the cached response. Purging any of those three surrogate keys will purge all cached responses tagged with that surrogate key.

Surrogate-Key: sports basketball march-tournament

Edgio Developer Console #

Use the Edgio Developer console to purge cached content within a specific environment.

To purge content

1. Load the Caching page.

   1. From the Edgio Developer console, select the desired private or team space.
   2. Select the desired property.
   3. From the left-hand pane, select the desired environment from under the Environments section.
   4. From the left-hand pane, select Caching.

2. From the Cache Purge History section, click Purge the Cache.

   

3. Purge:

   • All Cached Content: Select Purge all entries.
   • By Path: Select Purge by path. Specify each desired relative path on a separate line.
   • By Surrogate Key: Select Purge by surrogate key. Specify each desired surrogate key on a separate line.

4. Click Purge Cache.

5. When prompted, click Purge to confirm that your content will be purged.

Edgio CLI #

Purge cached content through the Edgio CLI by passing the cache-clear argument. You may purge:

• All content: Exclude the --path and --surrogate-key options.
• By relative path: Pass the --path option. You may use an * to represent zero or more characters.
• By surrogate key: Pass the --surrogate-key option. Learn more about surrogate keys.

Example:

Run the following command to purge the basketball surrogate key from the production environment from the my-videos property:

1edgio cache-clear --team=my-team --site=my-videos --environment=production --surrogate-key=basketball

REST API #

Purge cached content through the Edgio REST API through the clear-cache endpoint. You may purge:

• All content: Exclude the paths and surrogateKeys properties.
• By relative path: Pass the paths array of string values. You may use an * to represent zero or more characters.
• By surrogate key: Pass the surrogateKeys array of string values. Learn more about surrogate keys.

Deployments #

By default, all cached responses are purged from an environment when you deploy a new version of your site. Override this behavior by marking the Preserve cache between deployments setting on the Caching page.

Static prerendering after clearing the cache #

If you have enabled static prerendering, the cache will automatically be repopulated when you clear all entries from the cache (such as when you select Purge all entries in the Edgio Developer Console or run edgio cache-clear without providing --path or --surrogate-key). You can view the prerendering progress by clicking on the active deployment for the environment that was cleared.

Automated Purging #

Automate cache purging through NPM scripts and GitHub actions.

NPM Scripts #

Here is an example script you can add to your package.json to handle cache clearing for each environment. You can also configure scripts to clear by surrogate key, path, or group (As defined in Edgio Console)

These scripts assume that you have created environments called “production”, “staging”, and “development and you have created a deploy key for your site and added it as a secret in your repo called “edgio_deploy_token”.

1"scripts": {
2    ...
3    "clearcache:dev": "edgio cache-clear --team=myTeam --site=myEdgioApp --environment=development --token=$edgio_deploy_token",
4    "clearcache:stage": "edgio cache-clear --team=myTeam --site=myEdgioApp --environment=staging --token=$edgio_deploy_token",
5    "clearcache:prod": "edgio cache-clear --team=myTeam --site=myEdgioApp --environment=production --token=$edgio_deploy_token",
6    "clearcache:prod:pdps": "edgio cache-clear --team=myTeam --site=myEdgioApp --environment=production --surrogate-key=pdp --token=$edgio_deploy_token",
7    "clearcache:prod:plps": "edgio cache-clear --team=myTeam --site=myEdgioApp --environment=production --surrogate-key=plp --token=$edgio_deploy_token",
8    ...
9  },

GitHub Actions #

Here is an example GitHub action that clears the cache at a scheduled time using the jobs defined in your package.json

1# Add this file to your project at .github/workflows/clear-cache.yml
2#
3# This GitHub action clears the sites PRODUCTION cache at 09:15AM UTC every day.
4#
5# The schedule syntax is standard cron syntax
6# minute  hour  day-of-month  month day-of-week
7#   *      *         *          *        *
8#
9# 1.) This example depends on a script being defined in your package.json called clearcache:prod
10#
11# In order for this action to clear your cache, you must create a deploy token from the site settings page
12# in https://edgio.app and configure it as a secret called "edgio_deploy_token" in your repo on GitHub.
13
14name: Clear PRODUCTION cache at 5am
15on:
16  schedule:
17    - cron: '15 9 * * *'
18jobs:
19  clear-the-cache:
20    runs-on: ubuntu-latest
21    steps:
22      - name: Extract branch name
23        shell: bash
24        run: echo "BRANCH_NAME=$(echo ${GITHUB_REF#refs/heads/} | sed 's/\//_/g')" >> $GITHUB_ENV
25      - uses: actions/checkout@v1
26      - uses: actions/setup-node@v1
27        with:
28          node-version: 14
29          registry-url: https://npm-proxy.fury.io/layer0/
30      - name: Cache node modules
31        uses: actions/cache@v1
32        env:
33          cache-name: cache-node-modules
34        with:
35          path: ~/.npm # npm cache files are stored in `~/.npm` on Linux/macOS
36          key: ${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('**/package-lock.json') }}
37          restore-keys: |
38            ${{ runner.os }}-build-${{ env.cache-name }}-
39            ${{ runner.os }}-build-
40            ${{ runner.os }}-
41      - run: npm ci
42      - name: Clear cache in production
43        run: npm run clearcache:prod
44        env:
45          edgio_deploy_token: ${{secrets.edgio_deploy_token}}