open-nomad/ui/app/services/stats-trackers-registry.js

62 lines
2.1 KiB
JavaScript

import { computed } from '@ember/object';
import Service, { inject as service } from '@ember/service';
import { LRUMap } from 'lru_map';
import NodeStatsTracker from 'nomad-ui/utils/classes/node-stats-tracker';
import AllocationStatsTracker from 'nomad-ui/utils/classes/allocation-stats-tracker';
// An unbounded number of stat trackers is a great way to gobble up all the memory
// on a machine. This max number is unscientific, but aims to balance losing
// stat trackers a user is likely to return to with preventing gc from freeing
// memory occupied by stat trackers a user is likely to no longer care about
const MAX_STAT_TRACKERS = 10;
let registry;
const exists = (tracker, prop) =>
tracker.get(prop) && !tracker.get(prop).isDestroyed && !tracker.get(prop).isDestroying;
export default class StatsTrackersRegistryService extends Service {
@service token;
constructor() {
super(...arguments);
// The LRUMap limits the number of trackers tracked by making room for
// new entries beyond the limit by removing the least recently used entry.
registry = new LRUMap(MAX_STAT_TRACKERS);
}
// A read-only way of getting a reference to the registry.
// Since this could be overwritten by a bad actor, it isn't
// used in getTracker
@computed
get registryRef() {
return registry;
}
getTracker(resource) {
if (!resource) return;
const type = resource && resource.constructor.modelName;
const key = `${type}:${resource.get('id')}`;
const Constructor = type === 'node' ? NodeStatsTracker : AllocationStatsTracker;
const resourceProp = type === 'node' ? 'node' : 'allocation';
const cachedTracker = registry.get(key);
if (cachedTracker) {
// It's possible for the resource on a cachedTracker to have been
// deleted. Rebind it if that's the case.
if (!exists(cachedTracker, resourceProp)) cachedTracker.set(resourceProp, resource);
return cachedTracker;
}
const tracker = Constructor.create({
fetch: url => this.token.authorizedRequest(url),
[resourceProp]: resource,
});
registry.set(key, tracker);
return tracker;
}
}