An early look at what hot reloading might look like in the ember ecosystem
ember install ember-cli-hot-loader
During installation Ember CLI will prompt you to update the resolver code. This is required for ember-cli-hot-loader to work. If you have never modified the resolver, you can simply accept the changes or do a diff and update it manually. The final code should look something like:
import Resolver from 'ember-resolver';
import HotReloadMixin from 'ember-cli-hot-loader/mixins/hot-reload-resolver';
export default Resolver.extend(HotReloadMixin);
note: The HotReloadMixin is replaced with an empty Mixin for production/test builds
After the ember install simply run ember serve
as you normally would. Any changes to component JS/HBS files will result in a hot reload (not a full page reload). If you alter a route, service, controller or controller template ember-cli will do a full page reload.
If you want to exclude any component(s) from hot reloading simply configure them using excluded
//my-app/config/environment.js
if (environment === 'development') {
ENV['ember-cli-hot-loader'] = {
excluded: ['liquid-unless', 'liquid-child']
}
}
If you want to get more control over any component(s) excluding from hot reloading you can implement custom logic in resolver mixin method, named shouldExcludeComponent
.
For example if we don't want to reload ember-bootstrap
components -
we need to exclude all components with names started with bs-
prefix.
Working example available at lifeart/ember-hot-reload-demo (bs + non-reloadable bs-button
component)
import Resolver from 'ember-resolver';
import HotReloadMixin from 'ember-cli-hot-loader/mixins/hot-reload-resolver';
import Mixin from '@ember/object/mixin';
const CustomHotReloadMixin = Mixin.create(HotReloadMixin, {
shouldExcludeComponent({name}) {
const excludedFromConfig = this._super(...arguments);
const isBootstrapComponent = name.startsWith('bs-');
return excludedFromConfig || isBootstrapComponent;
}
});
export default Resolver.extend(CustomHotReloadMixin);
If you prefer to avoid the extra div that wraps each hot reloaded component configure it with tagless. Note: the tagless configuration does not support components that receive controller actions.
//my-app/config/environment.js
if (environment === 'development') {
ENV['ember-cli-hot-loader'] = {
tagless: true
}
}
An example application that hot reloads styles/components/reducers
https://github.com/toranb/ember-hot-reload-demo
- ember-cli will hot reload styles for you when using ember-cli 2.3+
- ember-cli-hot-loader will hot reload component JS/HBS changes
- to hot reload another file type, such as reducers you need to first enable it:
//my-app/config/environment.js
if (environment === 'development') {
ENV['ember-cli-hot-loader'] = {
supportedTypes: ['components', 'reducers']
}
}
Next write a service that will respond to the events willLiveReload
and willHotReload
import Service from '@ember/service';
import Evented from '@ember/object/evented';
export default Service.extend(Evented, {
init () {
this._super(...arguments);
this.on('willLiveReload', this, 'confirmLiveReload');
this.on('willHotReload', this, 'attemptHotReload');
},
confirmLiveReload(event) {
const module = getModulePath(event.modulePath);
if (module) {
event.cancel = true;
window.requirejs.unsee(module);
}
},
attemptHotReload(modulePath) {
const module = getModulePath(modulePath);
if (module) {
// re-render, replace module, etc
}
}
});
https://github.com/ember-redux/ember-redux-hot-loader
There is a known issue when used in conjunction with ember-cli-content-security-policy or any strong Content Security Policy that blocks "unsafe-eval"
(as it should).
When this plugin tries to execute the Ember.HTMLBars.compile
function, a CSP (Content Security Policy) that does not allow "unsafe-eval"
will block the JS execution with the following error:
Uncaught EvalError: Refused to evaluate a string as JavaScript
because 'unsafe-eval' is not an allowed source of script in the
following Content Security Policy directive: "script-src ...
To workaround this issue, in the config/environment.js
file, add "unsafe-eval"
to the Development and Test environment sections. Do NOT just add "unsafe-eval"
to the CSP that goes to Production as this will defeat one of the main safeguards that comes from using a CSP. Here is sample code to add to the CSP in the proper environments only:
// config/environment.js
ENV.contentSecurityPolicy = {
// normal CSP for Production here
}
if (environment === 'development') {
// ...
// Allow unsafe eval on dev environment
ENV.contentSecurityPolicy['script-src'].push("'unsafe-eval'");
}
if (environment === 'test') {
// ...
// Allow unsafe eval on test environment
ENV.contentSecurityPolicy['script-src'].push("'unsafe-eval'");
}