Files
OSIT-AE-App-Svelte/src/lib/stores/store_versions.ts
2026-03-24 13:27:40 -04:00

63 lines
2.4 KiB
TypeScript

/**
* store_versions.ts
*
* Single source of truth for persisted store schema versions.
*
* HOW IT WORKS:
* This file is imported at the top of ae_stores.ts and ae_events_stores.ts.
* ES modules resolve imports before running the importing module's body,
* so the version check + localStorage wipe here runs BEFORE persisted() is
* called — meaning stale data is cleared before svelte-persisted-store
* can hydrate from it.
*
* HOW TO USE:
* When a store schema changes in a breaking way (type change, required
* restructure, field rename that code depends on), bump the relevant version
* by 1. Any client with an older version will have that store silently wiped
* on next page load. They re-initialize from the new defaults.
*
* WHAT COUNTS AS BREAKING:
* - Changing a field's type (e.g. string → object, or null → required object)
* - Renaming a field that code reads directly (not just a display label)
* - Restructuring a nested object that breaks existing property access
* DOES NOT require a bump:
* - Adding a new optional field (svelte-persisted-store deep-merges defaults)
* - Removing a field (old value is ignored, no error)
* - Changing a default value when the stored value being stale is acceptable
*
* localStorage keys:
* 'ae_loc' → AE_LOC_VERSION
* 'ae_events_loc' → AE_EVENTS_LOC_VERSION
*/
export const AE_LOC_VERSION = 1;
export const AE_EVENTS_LOC_VERSION = 1;
// Version check side-effect: runs on import, before any persisted() call.
// Guards typeof localStorage for safety (SSR environments, test runners).
if (typeof localStorage !== 'undefined') {
_check_and_wipe('ae_loc', AE_LOC_VERSION);
_check_and_wipe('ae_events_loc', AE_EVENTS_LOC_VERSION);
}
function _check_and_wipe(key: string, expected_version: number): void {
try {
const raw = localStorage.getItem(key);
if (!raw) return; // No stored value — nothing to wipe.
const parsed = JSON.parse(raw);
if (parsed?.__version !== expected_version) {
localStorage.removeItem(key);
console.info(
`[store_versions] '${key}' wiped — schema v${parsed?.__version ?? 'none'} → v${expected_version}`
);
}
} catch {
// Corrupt JSON — wipe unconditionally.
localStorage.removeItem(key);
console.warn(
`[store_versions] '${key}' wiped — corrupt JSON in localStorage`
);
}
}