mkruisselbrink
commented
10 years ago Discovery certainly seems like an interesting feature to have, and one that would enable all kinds of cool use-cases. I'm not sure if it makes much sense to include in this initial version of the spec though, since it would make things a lot more complicated. Presumably for a discovery service to be useful you don't just want to know all the services that are available, but you want to know what services implement some specific API. Something like this seems to be what you're proposing?
// service worker:
self.onactivate = function(e) {
self.exposeService('/services/notify', 'com.rektide.Notify')
};
// other event handlers...
// client code:
navigator.getServices('com.rektide.Notify').then(
function(services) {
navigator.connect(services[0]).then(
function(port) {
// ....
}
);
}
);One reason to not include this in at least a first iteration of this spec is that most of this can actually be implemented using navigator.connect. You can implement your own discovery service as a navigator.connect exposed API (with a known URL); other services can then register with this discovery service, and clients can query the discovery service to get a list of services. Something like this (ignoring how to actually implement the discovery service and how to make sure the discovery service is available):
// service worker:
self.onactivate = function(e) {
e.waitUntil(navigator.connect('https://rektide.com/discoveryservice/register').then(
function(port) {
port.postMessage({url: 'https://example.com/services/notify', action: 'com.rektide.Notify'});
}
));
};
// other event handlers...
// client code:
navigator.connect('https://rektide.com/discoveryservice/lookup').then(
function(discoveryPort) {
discoveryPort.postMessage({action: 'com.rektide.Notify'});
discoveryPort.onmessage = function(event) {
var services = event.data.services;
navigator.connect(services[0]).then(
function(port) {
// ....
}
);
};
}
);(and all that extra boilerplate could of course be wrapped in convenience methods).
rektide
I would like to be able to advertise my ServiceWorker's willingness to be connected to. External/other-domained ServiceWorkerGlobalScopes should be able to elect to get notice of a connect-to URL that I broadcast to any receiving ServiceWorkerGlobalScopes.
This would deprecate my desire for a
chrome.extensions.discoverycapability.