I am using the serviceworker-rails gem to make my eCommerce application a progressive web app. Here is a gem file snippet from the project;
# progressive web application gem
gem 'serviceworker-rails'
# eCommerce gems
gem 'solidus'
gem 'solidus_auth_devise'
#base gems
gem 'rails', '~> 5.2.0'
ruby '2.5.1'
the serviceworker-rails gem in turn generates the manifest files needed to make the app a progressive web application;
app/assets/javascripts/serviceworker.js.erb
var CACHE_VERSION = 'v1';
var CACHE_NAME = CACHE_VERSION + ':sw-cache-';
function onInstall(event) {
console.log('[Serviceworker]', "Installing!", event);
event.waitUntil(
caches.open(CACHE_NAME).then(function prefill(cache) {
return cache.addAll([
// make sure serviceworker.js is not required by application.js
// if you want to reference application.js from here
'<%#= asset_path "application.js" %>',
'<%= asset_path "application.css" %>',
'/offline.html',
]);
})
);
}
function onActivate(event) {
console.log('[Serviceworker]', "Activating!", event);
event.waitUntil(
caches.keys().then(function(cacheNames) {
return Promise.all(
cacheNames.filter(function(cacheName) {
// Return true if you want to remove this cache,
// but remember that caches are shared across
// the whole origin
return cacheName.indexOf(CACHE_VERSION) !== 0;
}).map(function(cacheName) {
return caches.delete(cacheName);
})
);
})
);
}
// Borrowed from https://github.com/TalAter/UpUp
function onFetch(event) {
event.respondWith(
// try to return untouched request from network first
fetch(event.request).catch(function() {
// if it fails, try to return request from the cache
return caches.match(event.request).then(function(response) {
if (response) {
return response;
}
// if not found in cache, return default offline content for navigate requests
if (event.request.mode === 'navigate' ||
(event.request.method === 'GET' && event.request.headers.get('accept').includes('text/html'))) {
console.log('[Serviceworker]', "Fetching offline content", event);
return caches.match('/offline.html');
}
})
})
);
}
self.addEventListener('install', onInstall);
self.addEventListener('activate', onActivate);
self.addEventListener('fetch', onFetch);
app/assets/javascripts/serviceworker-companion.js
if (navigator.serviceWorker) {
navigator.serviceWorker.register('/serviceworker.js', { scope: './' })
.then(function(reg) {
console.log('[Companion]', 'Service worker registered!');
});
}
The application does not raise up any errors; just that I happen to notice that the service worker is not being registered. Here is the manifest in use;
app/assets/javascripts/manifest.json.erb
{
"name": "My Progressive Rails App",
"short_name": "Progressive",
"start_url": "/"
}
...and finally;
app/views/layouts/application.html.erb
<!DOCTYPE html>
<html>
<head>
<title>Istore</title>
<%= csrf_meta_tags %>
<%= csp_meta_tag %>
<%= stylesheet_link_tag 'application', media: 'all', 'data-turbolinks-track': 'reload' %>
<%= javascript_include_tag 'application', 'data-turbolinks-track': 'reload' %>
<link rel="manifest" href="/manifest.json" />
<meta name="apple-mobile-web-app-capable" content="yes">
</head>
<body>
<%= yield %>
</body>
</html>
To be fair; I have used this set up before and it worked good. Something breaks when I use it with solidus_gem. So far; my efforts to debug the issue has only zeroed me in on a set of probabilities. The strongest being; lack of a root directive.
(the gem also doesn't work for the default rails starter page)
But upon setting a custom root page; the gem works. So I did some monkey patching and added the solidus' root page to my project then appended the application routes to include the solidus home page.
config/routes.rb
Rails.application.routes.draw do
root to: 'spree/home#index'
mount Spree::Core::Engine, at: '/'
end
This has proven unsuccessful. I am using lighthouse to audit the application and the error signifies that the serviceworker is not being registered.
What am I missing? Is something out of scope?
I finally got it to work :) . The gem supplying the application layout is solidus but the problem is that the manifest is in the local application within which solidus is a gem.
To make it visible to the gem; I removed the tags from
app/views/layouts/application.html.erb
and then put them in the gems layout file. You have to download it locally to make changes. The layout file as of writing this is at
app/views/spree/layouts/
but the head section contains a render of a _head partial at
app/views/spree/shared/_head.html.erb
from where it is more efficient to place these tags inside to resolve the issue.
<%= javascript_include_tag "application" %>
<link rel="manifest" href="/manifest.json" />
<meta name="apple-mobile-web-app-capable" content="yes">