CDN and Versions

Note: This page covers advanced Workbox configuration. Most applications should use the default configuration documented in the Workbox README.

Default Configuration

The bundle ships with Workbox 7.3.0 (released October 2024) and serves all files locally from your application server. This provides:

• Faster loading (same-origin)

• Offline availability immediately

• No external dependencies

• Better privacy

• Controlled updates

/config/packages/pwa.yaml

pwa:
    serviceworker:
        workbox:
            use_cdn: false  # Default
            version: "7.3.0"  # Default

Available Versions

The bundle includes these Workbox versions locally:

• 7.3.0 (default, recommended)

• 7.0.0 (for compatibility if needed)

Using a CDN

For quick prototyping or bandwidth considerations, you can load Workbox from a CDN:

/config/packages/pwa.yaml

pwa:
    serviceworker:
        enabled: true
        src: "sw.js"
        workbox:
            use_cdn: true
            version: "7.3.0"

When use_cdn: true, Workbox files are loaded from https://storage.googleapis.com/workbox-cdn/releases/{version}/.

CDN Pros

• No local storage: Workbox files not bundled with your app

• Shared cache: Users may already have Workbox cached from other sites

• Always latest: Can easily switch versions

• Reduced deploy size: Slightly smaller deployment

CDN Cons

• External dependency: Requires Google's CDN to be available

• Network request: Adds latency on first load

• Privacy: Third-party request (though Google doesn't track via Workbox CDN)

• Offline delay: Service worker can't work until Workbox loads

• Version risk: CDN outages affect your app

Production Recommendation: Use local installation (use_cdn: false) for production applications. The benefits of local hosting far outweigh the small bandwidth savings of a CDN.

Custom Versions

You can specify any Workbox version when using the CDN:

/config/packages/pwa.yaml

pwa:
    serviceworker:
        workbox:
            use_cdn: true
            version: "6.5.4"  # Older version

Version Selection Guidelines

Use 7.3.0 (default) when:

• Starting a new project

• No specific compatibility requirements

• Want the latest features and fixes

Use 7.0.0 when:

• Need stability over new features

• Specific compatibility requirements

• Team has testing/docs for 7.0.0

Use 6.x when:

• Legacy project already using Workbox 6.x

• Breaking changes in 7.x affect your application

• Need to maintain compatibility with older code

Major Version Upgrades: Workbox 7.x includes breaking changes from 6.x. Review the Workbox migration guide before upgrading.

Complete Configuration Examples

Local Installation (Recommended)

/config/packages/pwa.yaml

pwa:
    serviceworker:
        enabled: true
        src: "sw.js"
        workbox:
            enabled: true
            use_cdn: false          # Local files (default)
            version: "7.3.0"        # Latest bundled version
            workbox_public_url: "/workbox"  # Where Workbox is served
            idb_public_url: "/idb"          # Where IndexedDB lib is served

CDN Installation

/config/packages/pwa.yaml

pwa:
    serviceworker:
        enabled: true
        src: "sw.js"
        workbox:
            enabled: true
            use_cdn: true           # Load from Google CDN
            version: "7.3.0"        # Version to load

Legacy Version with CDN

/config/packages/pwa.yaml

pwa:
    serviceworker:
        enabled: true
        src: "sw.js"
        workbox:
            enabled: true
            use_cdn: true
            version: "6.5.4"        # Older version for compatibility

Custom Public URLs (Local Only)

When using local installation, customize where Workbox files are served:

/config/packages/pwa.yaml

pwa:
    serviceworker:
        workbox:
            use_cdn: false
            workbox_public_url: "/assets/workbox"
            idb_public_url: "/assets/idb"

This is useful when:

• Organizing assets by type

• Complying with specific URL structures

• Integrating with CDN configurations

Checking Your Configuration

To verify which Workbox version and source is being used:

1. Open DevTools (F12)

2. Go to Application → Service Workers

3. View service worker source

4. Look for importScripts() calls at the top

Local installation:

importScripts('/workbox/workbox-sw.js');

CDN installation:

importScripts('https://storage.googleapis.com/workbox-cdn/releases/7.3.0/workbox-sw.js');

Version Update Process

When updating Workbox versions:

1. Review changelog: Check Workbox releases for breaking changes

2. Update configuration: Change version in pwa.yaml

3. Clear caches: Clear browser caches during testing

4. Test thoroughly: Test all caching strategies and offline functionality

5. Monitor: Watch for errors after deployment

Troubleshooting

Workbox not loading?

• Check CDN availability if use_cdn: true

• Verify version is correct and available

• Check browser console for import errors

• Ensure service worker is registered

Using CDN but want to switch to local?

workbox:
    use_cdn: false  # Switch to local
    version: "7.3.0"

Then clear caches and re-register service worker.

Using local but Workbox not found?

• Verify bundle provides the version you specified

• Check workbox_public_url is accessible

• Look for 404 errors in Network tab

Best Practice: Start with local installation using the default version. Only use CDN for quick prototyping or specific use cases where bandwidth is critical and reliability of an external CDN is acceptable.