import openDB from './db'; const accountAssetKeys = ['avatar', 'avatar_static', 'header', 'header_static']; const storageMargin = 8388608; const storeLimit = 1024; function openCache() { // ServiceWorker and Cache API is not available on iOS 11 // https://webkit.org/status/#specification-service-workers return self.caches ? caches.open('mastodon-system') : Promise.reject(); } function printErrorIfAvailable(error) { if (error) { console.warn(error); } } function put(name, objects, onupdate, oncreate) { return openDB().then(db => (new Promise((resolve, reject) => { const putTransaction = db.transaction(name, 'readwrite'); const putStore = putTransaction.objectStore(name); const putIndex = putStore.index('id'); objects.forEach(object => { putIndex.getKey(object.id).onsuccess = retrieval => { function addObject() { putStore.add(object); } function deleteObject() { putStore.delete(retrieval.target.result).onsuccess = addObject; } if (retrieval.target.result) { if (onupdate) { onupdate(object, retrieval.target.result, putStore, deleteObject); } else { deleteObject(); } } else { if (oncreate) { oncreate(object, addObject); } else { addObject(); } } }; }); putTransaction.oncomplete = () => { const readTransaction = db.transaction(name, 'readonly'); const readStore = readTransaction.objectStore(name); const count = readStore.count(); count.onsuccess = () => { const excess = count.result - storeLimit; if (excess > 0) { const retrieval = readStore.getAll(null, excess); retrieval.onsuccess = () => resolve(retrieval.result); retrieval.onerror = reject; } else { resolve([]); } }; count.onerror = reject; }; putTransaction.onerror = reject; })).then(resolved => { db.close(); return resolved; }, error => { db.close(); throw error; })); } function evictAccountsByRecords(records) { return openDB().then(db => { const transaction = db.transaction(['accounts', 'statuses'], 'readwrite'); const accounts = transaction.objectStore('accounts'); const accountsIdIndex = accounts.index('id'); const accountsMovedIndex = accounts.index('moved'); const statuses = transaction.objectStore('statuses'); const statusesIndex = statuses.index('account'); function evict(toEvict) { toEvict.forEach(record => { openCache() .then(cache => accountAssetKeys.forEach(key => cache.delete(records[key]))) .catch(printErrorIfAvailable); accountsMovedIndex.getAll(record.id).onsuccess = ({ target }) => evict(target.result); statusesIndex.getAll(record.id).onsuccess = ({ target }) => evictStatusesByRecords(target.result); accountsIdIndex.getKey(record.id).onsuccess = ({ target }) => target.result && accounts.delete(target.result); }); } evict(records); db.close(); }).catch(printErrorIfAvailable); } export function evictStatus(id) { evictStatuses([id]); } export function evictStatuses(ids) { return openDB().then(db => { const transaction = db.transaction('statuses', 'readwrite'); const store = transaction.objectStore('statuses'); const idIndex = store.index('id'); const reblogIndex = store.index('reblog'); ids.forEach(id => { reblogIndex.getAllKeys(id).onsuccess = ({ target }) => target.result.forEach(reblogKey => store.delete(reblogKey)); idIndex.getKey(id).onsuccess = ({ target }) => target.result && store.delete(target.result); }); db.close(); }).catch(printErrorIfAvailable); } function evictStatusesByRecords(records) { return evictStatuses(records.map(({ id }) => id)); } export function putAccounts(records, avatarStatic) { const avatarKey = avatarStatic ? 'avatar_static' : 'avatar'; const newURLs = []; put('accounts', records, (newRecord, oldKey, store, oncomplete) => { store.get(oldKey).onsuccess = ({ target }) => { accountAssetKeys.forEach(key => { const newURL = newRecord[key]; const oldURL = target.result[key]; if (newURL !== oldURL) { openCache() .then(cache => cache.delete(oldURL)) .catch(printErrorIfAvailable); } }); const newURL = newRecord[avatarKey]; const oldURL = target.result[avatarKey]; if (newURL !== oldURL) { newURLs.push(newURL); } oncomplete(); }; }, (newRecord, oncomplete) => { newURLs.push(newRecord[avatarKey]); oncomplete(); }).then(records => Promise.all([ evictAccountsByRecords(records), openCache().then(cache => cache.addAll(newURLs)), ])).then(freeStorage, error => { freeStorage(); throw error; }).catch(printErrorIfAvailable); } export function putStatuses(records) { put('statuses', records) .then(evictStatusesByRecords) .catch(printErrorIfAvailable); } export function freeStorage() { // navigator.storage is not present on: // Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.100 Safari/537.36 Edge/16.16299 return 'storage' in navigator && navigator.storage.estimate().then(({ quota, usage }) => { if (usage + storageMargin < quota) { return null; } return openDB().then(db => new Promise((resolve, reject) => { const retrieval = db.transaction('accounts', 'readonly').objectStore('accounts').getAll(null, 1); retrieval.onsuccess = () => { if (retrieval.result.length > 0) { resolve(evictAccountsByRecords(retrieval.result).then(freeStorage)); } else { resolve(caches.delete('mastodon-system')); } }; retrieval.onerror = reject; db.close(); })); }); }