hometown/app/javascript/mastodon/storage/modifier.js
2018-04-08 13:32:39 +02:00

207 lines
5.7 KiB
JavaScript

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() {
return 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();
}));
});
}