Storage Quota Management in JavaScript

1// Method 1: Check storage quota
2async function getStorageQuota() {
3    if ('storage' in navigator && 'estimate' in navigator.storage) {
4        const estimate = await navigator.storage.estimate();
5        console.log('Quota:', estimate.quota);
6        console.log('Usage:', estimate.usage);
7        console.log('Available:', estimate.quota - estimate.usage);
8        console.log('Usage %:', ((estimate.usage / estimate.quota) * 100).toFixed(2) + '%');
9        return estimate;
10    }
11    return null;
12}
13
14getStorageQuota();
15
16// Method 2: Check localStorage size
17function getLocalStorageSize() {
18    let total = 0;
19    for (let key in localStorage) {
20        if (localStorage.hasOwnProperty(key)) {
21            total += localStorage[key].length + key.length;
22        }
23    }
24    return total;
25}
26
27const size = getLocalStorageSize();
28console.log('LocalStorage size:', size, 'bytes');
29console.log('Size in KB:', (size / 1024).toFixed(2));
30
31// Method 3: Check if storage is full
32function isStorageFull() {
33    try {
34        const test = '__storage_test__';
35        localStorage.setItem(test, 'test');
36        localStorage.removeItem(test);
37        return false;
38    } catch (e) {
39        return e.name === 'QuotaExceededError' || e.name === 'NS_ERROR_DOM_QUOTA_REACHED';
40    }
41}
42
43if (isStorageFull()) {
44    console.log('Storage is full');
45} else {
46    console.log('Storage has space');
47}
48
49// Method 4: Clear old data when full
50function setItemWithCleanup(key, value) {
51    try {
52        localStorage.setItem(key, value);
53    } catch (e) {
54        if (e.name === 'QuotaExceededError') {
55            console.log('Storage full, clearing old data...');
56            // Clear items older than 7 days
57            clearOldItems(7);
58            // Try again
59            localStorage.setItem(key, value);
60        } else {
61            throw e;
62        }
63    }
64}
65
66function clearOldItems(days) {
67    const cutoff = Date.now() - (days * 24 * 60 * 60 * 1000);
68    for (let i = localStorage.length - 1; i >= 0; i--) {
69        const key = localStorage.key(i);
70        const item = localStorage.getItem(key);
71        try {
72            const data = JSON.parse(item);
73            if (data.timestamp && data.timestamp < cutoff) {
74                localStorage.removeItem(key);
75            }
76        } catch (e) {
77            // Not JSON, skip
78        }
79    }
80}
81
82// Method 5: Monitor storage usage
83function monitorStorage() {
84    setInterval(async () => {
85        const estimate = await navigator.storage.estimate();
86        const usagePercent = (estimate.usage / estimate.quota) * 100;
87        
88        if (usagePercent > 80) {
89            console.warn('Storage usage high:', usagePercent.toFixed(2) + '%');
90        }
91    }, 60000); // Check every minute
92}
93
94// Method 6: Request persistent storage
95async function requestPersistentStorage() {
96    if ('storage' in navigator && 'persist' in navigator.storage) {
97        const isPersistent = await navigator.storage.persist();
98        console.log('Persistent storage granted:', isPersistent);
99        return isPersistent;
100    }
101    return false;
102}
103
104requestPersistentStorage();