Updates

client/jsonCache.js

@@ -0,0 +1,133 @@
+/**
+ * Atomic JSON cache under ~/.config/peardata/cache/{name}.json
+ * (+ optional localStorage mirror / legacy migration).
+ */
+import fs from 'fs'
+import path from 'path'
+import { getPeardataCacheDir } from './paths.js'
+
+export const JSON_CACHE_VERSION = 1
+export const JSON_CACHE_LS_PREFIX = 'peardata.cache.'
+
+/**
+ * @param {string} name
+ */
+export function sanitizeCacheName(name) {
+  const s = String(name || '')
+    .trim()
+    .toLowerCase()
+    .replace(/[^a-z0-9._-]+/g, '-')
+    .replace(/^-+|-+$/g, '')
+  if (!s || s === '.' || s === '..') throw new Error(`Invalid cache name: ${name}`)
+  return s
+}
+
+/**
+ * @param {string} name
+ */
+export function getCacheFilePath(name) {
+  return path.join(getPeardataCacheDir(), `${sanitizeCacheName(name)}.json`)
+}
+
+/**
+ * @param {string} name
+ */
+export function getCacheLocalStorageKey(name) {
+  return JSON_CACHE_LS_PREFIX + sanitizeCacheName(name)
+}
+
+/**
+ * @param {string} file
+ * @param {object} payload
+ */
+export function atomicWriteJson(file, payload) {
+  const dir = path.dirname(file)
+  fs.mkdirSync(dir, { recursive: true, mode: 0o700 })
+  const json = JSON.stringify(payload, null, 2)
+  const tmp = `${file}.${process.pid}.${Date.now()}.tmp`
+  fs.writeFileSync(tmp, json, { mode: 0o600 })
+  fs.renameSync(tmp, file)
+  try {
+    fs.chmodSync(file, 0o600)
+  } catch {
+    // ignore
+  }
+}
+
+/**
+ * @param {string} name
+ * @param {unknown} data
+ * @param {{ mirrorLocalStorage?: boolean }} [opts]
+ */
+export function saveJsonCache(name, data, opts = {}) {
+  const file = getCacheFilePath(name)
+  const payload = {
+    version: JSON_CACHE_VERSION,
+    updatedAt: new Date().toISOString(),
+    data,
+  }
+  try {
+    atomicWriteJson(file, payload)
+  } catch (err) {
+    console.warn('[WARN] jsonCache: write failed', name, err?.message || err)
+  }
+  if (opts.mirrorLocalStorage !== false) {
+    try {
+      if (typeof localStorage !== 'undefined') {
+        localStorage.setItem(getCacheLocalStorageKey(name), JSON.stringify(payload))
+      }
+    } catch {
+      // ignore
+    }
+  }
+  return data
+}
+
+/**
+ * @param {string} name
+ * @param {{ legacyLocalStorageKey?: string, defaultValue?: unknown }} [opts]
+ */
+export function loadJsonCache(name, opts = {}) {
+  const file = getCacheFilePath(name)
+  try {
+    if (fs.existsSync(file)) {
+      const raw = JSON.parse(fs.readFileSync(file, 'utf8'))
+      if (raw && typeof raw === 'object' && 'data' in raw) return raw.data
+      return raw
+    }
+  } catch {
+    // fall through
+  }
+
+  // Legacy localStorage migration
+  if (opts.legacyLocalStorageKey) {
+    try {
+      if (typeof localStorage !== 'undefined') {
+        const legacy = localStorage.getItem(opts.legacyLocalStorageKey)
+        if (legacy) {
+          const parsed = JSON.parse(legacy)
+          const data =
+            parsed && typeof parsed === 'object' && 'data' in parsed ? parsed.data : parsed
+          saveJsonCache(name, data ?? opts.defaultValue ?? null)
+          return data ?? opts.defaultValue ?? null
+        }
+      }
+    } catch {
+      // ignore
+    }
+  }
+
+  try {
+    if (typeof localStorage !== 'undefined') {
+      const mir = localStorage.getItem(getCacheLocalStorageKey(name))
+      if (mir) {
+        const parsed = JSON.parse(mir)
+        return parsed && typeof parsed === 'object' && 'data' in parsed ? parsed.data : parsed
+      }
+    }
+  } catch {
+    // ignore
+  }
+
+  return opts.defaultValue ?? null
+}