bornfight/service-workers

Service workers

Simple helper library for working with service workers. There are two main things that need to be remembered:

1. SSL is a requirement.
2. You have scoped access, so your worker.js needs to be in your root.

Main thread

On your main thread, you need to include main-thread/ServiceWorker.js.

After that, just register your worker with new object.

(function(){

    var worker = new com.degordian.common.helpers.ServiceWorker('/worker.example.js');
    worker.register();

})();

That's it on your main thread.

Service worker thread

There are few things that need to be done on this thread:

1. Include workers definitions.
2. Initialize new worker.
3. Set definitions.

Definition of workers is in service-workers.js file.

importScripts('/path/to/service-workers.js');

It's good practice to set constants for further usage. Also, don't forget to pass context to worker.

var baseUrl = "https://your.base.url";
var context = self;
var version = "1";
var cacheKey = "cache" + version;

var worker = new com.degordian.common.ServiceWorker(self);

// Worker definitions
// TODO: wiil be filled

// Initialize worker
worker.init();

Worker defined like this knows how to work with following interfaces:

1. Installable
2. Activable
3. Fetchable
4. Syncable

Pushable will be added in future builds. Each of this represent a single event in life cycle.

All interfaces have getRoutes function and if there is a match with an event, worker will be called and event object will be passed to it.

ONLY FETCHABLE KNOW HOW TO DEAL WITH REGEX!

There is a certain amount of implemented content serving methods. Here is a list of those implemented.

Worker name	Constructor	Description	Interfaces
OnInstallDependency	(routes, cacheKey)	Provided routes will be fetched and cached during the install event. If any of these fails, worker will not be installed.	Installable
OnInstallNoDependency	(dependentRoutes, nonDependentRoutes, cacheKey)	Similar to OnInstallDependency, with extra of non dependent files (if fetching those fails, worker will still install)	Installable
OnActivate	(caches)	Responsible for cache clearing. If cache name is not provided in caches, it will be deleted.	Activable
OnNetworkResponseCache	(routes, cacheKey)	Returns from cache. If there is no match in cache, network request is normally done. On it's completion, response is cached for further usage.	Fetchable
StaleWhileRevalidate	(routes, cacheKey)	If there is a cache match, respond to event with that and make a request to network and upon completion cache it. If there is no cache, standard network request.	Fetchable
RevalidateWithCacheFallback	(routes, cacheKey)	Do a network request and cache on success. On failure, return match from cache.	Fetchable
OnBackgroundSync	(ids, cacheKey)	When sync event is triggered, put to cache all with event id.	Syncable
CacheOnly	(routes)	Fetch only from cache	Fetchable
CacheFallingBackToNetwork	(routes)	Get from cache if there is a match, otherwise standard network request (with no cache at response)	Fetchable
CacheAndNetworkRace	(routes)	Which ever responds first with success.	Fetchable
NetworkFallingBackToCache	(routes)	If there is network, standard network request. If there is no network, get a match from cache.	Fetchable

Here are two examples for working with strings and regular expressions:

worker.registerWorker(
    new com.degordian.common.serviceWorkers.OnInstallDependecy([
        baseUrl + "static/js/app.js",
        baseUrl + "static/js/main.js",
    ])
);

worker.registerWorker(
    new com.degordian.common.serviceWorkers.CacheFallingBackToNetwork([
        /main\.js$/,
        /app\.js$/,
        /sdk\.js$/
    ])
);

Final worker.js example:

/*
 * Path to the service-workers.js file
 */
importScripts('/path/to/service-workers.js');

var baseUrl = "https://your.base.url";
var context = self;
var version = "1";
var cacheKey = "cache" + version;

var worker = new com.degordian.common.ServiceWorker(self);

// Worker definitions

worker.registerWorker(
    new com.degordian.common.serviceWorkers.OnInstallDependecy([
        baseUrl + "static/js/app.js",
        baseUrl + "static/js/main.js",
    ])
);

worker.registerWorker(
    new com.degordian.common.serviceWorkers.CacheFallingBackToNetwork([
        /main\.js$/,
        /app\.js$/,
        /sdk\.js$/
    ])
);

worker.registerWorker(
    new com.degordian.common.serviceWorkers.StaleWhileRevalidate([
        /\.(png|jpg|jpeg|gif)$/,
        /gtm\.js/,
    ])
);

// Initialize worker
worker.init();