Add app package

packages/app/src/freshness.ts

@@ -0,0 +1,22 @@
+import {writable} from 'svelte/store'
+import {assoc} from '@welshman/lib'
+import {withGetter} from '@welshman/store'
+
+export const freshness = withGetter(writable<Record<string, number>>({}))
+
+export const getFreshnessKey = (ns: string, key: string) => `${ns}:${key}`
+
+export const getFreshness = (ns: string, key: string) =>
+  freshness.get()[getFreshnessKey(ns, key)] || 0
+
+export const setFreshness = (ns: string, key: string, ts: number) =>
+  freshness.update(assoc(getFreshnessKey(ns, key), ts))
+
+export const setFreshnessBulk = (ns: string, updates: Record<string, number>) =>
+  freshness.update($freshness => {
+    for (const [key, ts] of Object.entries(updates)) {
+      $freshness[key] = ts
+    }
+
+    return $freshness
+  })