SiteGround Cache Manager

A GitHub Action to purge SiteGround caches (dynamic NGINX cache and Memcached object cache) directly from your CI/CD workflows.

Supports two operation modes:

• ssh (default) — Shared hosting. Connects via SSH and runs WP-CLI commands provided by the SG Optimizer plugin (which is preinstalled on every SiteGround WordPress site). This is the recommended approach for the vast majority of users.
• api — Agency-tier Site Tools API. Calls the SiteGround Site Tools REST API. Requires agency/reseller credentials.

Features

• Purge all caches (default) — clears both dynamic and memcached
• Purge dynamic cache only — clears the SG Optimizer/NGINX page cache
• Purge memcached only — flushes the WP object cache
• Passphrase-protected SSH keys — supported (SiteGround keys created in Site Tools always have a passphrase)
• KNOWN_HOSTS support — strict host key verification when provided

Quickstart

SSH mode (shared hosting — most common)

- name: Purge SiteGround Cache
  uses: fkwdigital/github-workflow-action-siteground-cache@v1
  with:
    SSH_PRIVATE_KEY: ${{ secrets.SSH_PRIVATE_KEY }}
    SSH_PASSPHRASE: ${{ secrets.SSH_PASSPHRASE }}
    KNOWN_HOSTS: ${{ secrets.KNOWN_HOSTS }}
    REMOTE_HOST: ${{ secrets.REMOTE_HOST }}
    REMOTE_USER: ${{ secrets.REMOTE_USER }}
    REMOTE_PATH: '/home/customer/www/example.com/public_html'

API mode (agency-tier)

- name: Purge SiteGround Cache (API)
  uses: fkwdigital/github-workflow-action-siteground-cache@v1
  with:
    MODE: 'api'
    SITEGROUND_API_TOKEN: ${{ secrets.SITEGROUND_API_TOKEN }}
    SITEGROUND_SITE_ID: ${{ secrets.SITEGROUND_SITE_ID }}

Inputs

Common

Input	Description	Required	Default
MODE	Operation mode: ssh (default) or api	No	ssh
CACHE_TYPE	What to purge: all (default), dynamic, or memcached	No	all

SSH mode (MODE=ssh)

Input	Description	Required	Default
SSH_PRIVATE_KEY	Private key contents	Yes	-
REMOTE_HOST	SSH host (SiteGround server hostname or IP)	Yes	-
REMOTE_USER	SSH username	Yes	-
REMOTE_PATH	Absolute path to the WP install (e.g. /home/customer/www/example.com/public_html)	Yes	-
SSH_PASSPHRASE	Passphrase for the private key. SiteGround keys created in Site Tools always have one.	No	-
KNOWN_HOSTS	Output of ssh-keyscan -H -p 18765 <host>. Strongly recommended — omitting disables host verification.	No	-
REMOTE_PORT	SSH port (SiteGround's default is 18765, not 22)	No	18765

API mode (MODE=api)

Input	Description	Required	Default
SITEGROUND_API_TOKEN	OAuth bearer token for the Site Tools API (agency/reseller required)	Yes	-
SITEGROUND_SITE_ID	Site ID from Site Tools	Yes	-
SITEGROUND_API_BASE	API base URL (override only if SiteGround changes endpoints)	No	https://api.siteground.com/v00

How it works

SSH mode

1. Writes SSH_PRIVATE_KEY to ~/.ssh/siteground_cache_key (mode 0600).
2. If SSH_PASSPHRASE is provided, strips it in-place using ssh-keygen -p so ssh -i can use the key without an interactive prompt.
3. If KNOWN_HOSTS is provided, appends it to ~/.ssh/known_hosts and uses StrictHostKeyChecking=yes.
4. Connects via SSH and runs the appropriate WP-CLI command(s) on the remote host.
5. Deletes the temporary key file on exit.

The remote commands are:

CACHE_TYPE	Remote command
all	wp sg purge --path=<REMOTE_PATH> && wp cache flush --path=<REMOTE_PATH>
dynamic	wp sg purge --path=<REMOTE_PATH>
memcached	wp cache flush --path=<REMOTE_PATH>

wp sg purge is provided by the SG Optimizer plugin (preinstalled on all SiteGround WordPress sites). wp cache flush is a built-in WP-CLI command that flushes the persistent object cache (which uses Memcached on SiteGround when the SG Optimizer plugin's "Memcached" toggle is enabled).

API mode

POSTs to SITEGROUND_API_BASE/sites/<SITE_ID>/<resource>/flush with a Bearer token, where <resource> is dynamic-cache, memcached, or both depending on CACHE_TYPE. This mode is intended for agency/reseller customers who already have a Site Tools API token.

SiteGround setup

Generate the SSH key (Site Tools)

1. Site Tools → Devs → SSH Keys Manager
2. Click Create
3. Set the passphrase (SiteGround requires one — there is no opt-out)
4. Download the private key
5. Upload the private key to GitHub Secrets as SSH_PRIVATE_KEY and the passphrase as SSH_PASSPHRASE

The matching public key is automatically authorized on the server.

Get host details

• REMOTE_HOST: Site Tools → Devs → SSH Keys Manager → look at the example connection string. Or use your domain.
• REMOTE_USER: same place — typically of the form u123-abc456.
• REMOTE_PATH: Site Tools → Site → File Manager. The WP install path is usually /home/customer/www/<domain>/public_html.

Get KNOWN_HOSTS (recommended)

Run locally once and paste the output into a GitHub secret:

ssh-keyscan -H -p 18765 your-siteground-host.com

Without KNOWN_HOSTS, the action falls back to StrictHostKeyChecking=no, which is vulnerable to MITM attacks.

Common workflows

Deploy then purge

name: Deploy to Production
on:
  push:
    branches: [main]

jobs:
  deploy:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Deploy via rsync
        uses: fkwdigital/github-workflow-action-ubuntu-rsync@v1
        with:
          SSH_PRIVATE_KEY: ${{ secrets.SSH_PRIVATE_KEY }}
          SSH_PASSPHRASE: ${{ secrets.SSH_PASSPHRASE }}
          KNOWN_HOSTS: ${{ secrets.KNOWN_HOSTS }}
          REMOTE_HOST: ${{ secrets.REMOTE_HOST }}
          REMOTE_USER: ${{ secrets.REMOTE_USER }}
          REMOTE_PORT: 18765
          REMOTE_PATH: '/home/customer/www/example.com/public_html'
          SOURCE: './public/'

      - name: Purge SiteGround Cache
        uses: fkwdigital/github-workflow-action-siteground-cache@v1
        with:
          SSH_PRIVATE_KEY: ${{ secrets.SSH_PRIVATE_KEY }}
          SSH_PASSPHRASE: ${{ secrets.SSH_PASSPHRASE }}
          KNOWN_HOSTS: ${{ secrets.KNOWN_HOSTS }}
          REMOTE_HOST: ${{ secrets.REMOTE_HOST }}
          REMOTE_USER: ${{ secrets.REMOTE_USER }}
          REMOTE_PATH: '/home/customer/www/example.com/public_html'

Purge dynamic cache only

- name: Purge SiteGround Dynamic Cache
  uses: fkwdigital/github-workflow-action-siteground-cache@v1
  with:
    SSH_PRIVATE_KEY: ${{ secrets.SSH_PRIVATE_KEY }}
    SSH_PASSPHRASE: ${{ secrets.SSH_PASSPHRASE }}
    REMOTE_HOST: ${{ secrets.REMOTE_HOST }}
    REMOTE_USER: ${{ secrets.REMOTE_USER }}
    REMOTE_PATH: '/home/customer/www/example.com/public_html'
    CACHE_TYPE: 'dynamic'

Manual purge (workflow_dispatch)

name: Purge SiteGround Cache
on:
  workflow_dispatch:
    inputs:
      cache_type:
        type: choice
        options: [all, dynamic, memcached]
        default: all

jobs:
  purge:
    runs-on: ubuntu-latest
    steps:
      - uses: fkwdigital/github-workflow-action-siteground-cache@v1
        with:
          SSH_PRIVATE_KEY: ${{ secrets.SSH_PRIVATE_KEY }}
          SSH_PASSPHRASE: ${{ secrets.SSH_PASSPHRASE }}
          KNOWN_HOSTS: ${{ secrets.KNOWN_HOSTS }}
          REMOTE_HOST: ${{ secrets.REMOTE_HOST }}
          REMOTE_USER: ${{ secrets.REMOTE_USER }}
          REMOTE_PATH: '/home/customer/www/example.com/public_html'
          CACHE_TYPE: ${{ github.event.inputs.cache_type }}

Troubleshooting

Permission denied (publickey)

• Make sure the key was created in SiteGround Site Tools and matches the user/host you're connecting as.
• If the key has a passphrase, you must pass SSH_PASSPHRASE.
• SiteGround's default SSH port is 18765, not 22.

wp: command not found

WP-CLI is preinstalled on every SiteGround managed WordPress site. If you're getting this on a non-WP application or a self-managed environment, install WP-CLI on the remote first.

Error: This is not a WordPress installation

REMOTE_PATH is wrong. It must be the directory containing wp-config.php. On SiteGround that's typically /home/customer/www/<domain>/public_html.

wp sg: not a registered subcommand

The SG Optimizer plugin isn't installed/active on that WordPress site. Install SG Optimizer (it's free in the WP plugin directory) or use CACHE_TYPE: memcached to skip the SG-specific purge.

API mode returns 404

The Site Tools API endpoint structure may differ depending on your agency tier. Override SITEGROUND_API_BASE if needed, or fall back to SSH mode.

License

MIT

Support

• Action issues: Open an issue on this repository
• SiteGround SSH/SG Optimizer docs: https://www.siteground.com/kb/