yomichan/ext/bg/js/generic-database.js
toasted-nutbread 244ab31bb2
Generic database (#600)
* Update test

* Rename db to _db

* Create GenericDatabase class

* Catch prepare error

* Allow database to be purged even if it was not open

* Remove unused functions

* Change static functions to non-static

* Delete and count using the media object store

* Update tests
2020-06-21 16:12:56 -04:00

328 lines
11 KiB
JavaScript

/*
* Copyright (C) 2020 Yomichan Authors
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
class GenericDatabase {
constructor() {
this._db = null;
this._isOpening = false;
}
// Public
async open(databaseName, version, structure) {
if (this._db !== null) {
throw new Error('Database already open');
}
if (this._isOpening) {
throw new Error('Already opening');
}
try {
this._isOpening = true;
this._db = await this._open(databaseName, version, (db, transaction, oldVersion) => {
this._upgrade(db, transaction, oldVersion, structure);
});
} finally {
this._isOpening = false;
}
}
close() {
if (this._db === null) {
throw new Error('Database is not open');
}
this._db.close();
this._db = null;
}
isOpening() {
return this._isOpening;
}
isOpen() {
return this._db !== null;
}
transaction(storeNames, mode) {
if (this._db === null) {
throw new Error(this._isOpening ? 'Database not ready' : 'Database not open');
}
return this._db.transaction(storeNames, mode);
}
bulkAdd(objectStoreName, items, start, count) {
return new Promise((resolve, reject) => {
if (start + count > items.length) {
count = items.length - start;
}
if (count <= 0) {
resolve();
return;
}
const end = start + count;
let completedCount = 0;
const onError = (e) => reject(e.target.error);
const onSuccess = () => {
if (++completedCount >= count) {
resolve();
}
};
const transaction = this.transaction([objectStoreName], 'readwrite');
const objectStore = transaction.objectStore(objectStoreName);
for (let i = start; i < end; ++i) {
const request = objectStore.add(items[i]);
request.onerror = onError;
request.onsuccess = onSuccess;
}
});
}
getAll(objectStoreOrIndex, query, resolve, reject) {
if (typeof objectStoreOrIndex.getAll === 'function') {
this._getAllFast(objectStoreOrIndex, query, resolve, reject);
} else {
this._getAllUsingCursor(objectStoreOrIndex, query, resolve, reject);
}
}
getAllKeys(objectStoreOrIndex, query, resolve, reject) {
if (typeof objectStoreOrIndex.getAll === 'function') {
this._getAllKeysFast(objectStoreOrIndex, query, resolve, reject);
} else {
this._getAllKeysUsingCursor(objectStoreOrIndex, query, resolve, reject);
}
}
find(objectStoreName, indexName, query, predicate=null, defaultValue) {
return new Promise((resolve, reject) => {
const transaction = this.transaction([objectStoreName], 'readonly');
const objectStore = transaction.objectStore(objectStoreName);
const objectStoreOrIndex = indexName !== null ? objectStore.index(indexName) : objectStore;
const request = objectStoreOrIndex.openCursor(query, 'next');
request.onerror = (e) => reject(e.target.error);
request.onsuccess = (e) => {
const cursor = e.target.result;
if (cursor) {
const value = cursor.value;
if (typeof predicate !== 'function' || predicate(value)) {
resolve(value);
} else {
cursor.continue();
}
} else {
resolve(defaultValue);
}
};
});
}
bulkCount(targets, resolve, reject) {
const targetCount = targets.length;
if (targetCount <= 0) {
resolve();
return;
}
let completedCount = 0;
const results = new Array(targetCount).fill(null);
const onError = (e) => reject(e.target.error);
const onSuccess = (e, index) => {
const count = e.target.result;
results[index] = count;
if (++completedCount >= targetCount) {
resolve(results);
}
};
for (let i = 0; i < targetCount; ++i) {
const index = i;
const [objectStoreOrIndex, query] = targets[i];
const request = objectStoreOrIndex.count(query);
request.onerror = onError;
request.onsuccess = (e) => onSuccess(e, index);
}
}
delete(objectStoreName, key) {
return new Promise((resolve, reject) => {
const transaction = this.transaction([objectStoreName], 'readwrite');
const objectStore = transaction.objectStore(objectStoreName);
const request = objectStore.delete(key);
request.onerror = (e) => reject(e.target.error);
request.onsuccess = () => resolve();
});
}
bulkDelete(objectStoreName, indexName, query, filterKeys=null, onProgress=null) {
return new Promise((resolve, reject) => {
const transaction = this.transaction([objectStoreName], 'readwrite');
const objectStore = transaction.objectStore(objectStoreName);
const objectStoreOrIndex = indexName !== null ? objectStore.index(indexName) : objectStore;
const onGetKeys = (keys) => {
try {
if (typeof filterKeys === 'function') {
keys = filterKeys(keys);
}
this._bulkDeleteInternal(objectStore, keys, onProgress, resolve, reject);
} catch (e) {
reject(e);
}
};
this.getAllKeys(objectStoreOrIndex, query, onGetKeys, reject);
});
}
static deleteDatabase(databaseName) {
return new Promise((resolve, reject) => {
const request = indexedDB.deleteDatabase(databaseName);
request.onerror = (e) => reject(e.target.error);
request.onsuccess = () => resolve();
request.onblocked = () => reject(new Error('Database deletion blocked'));
});
}
// Private
_open(name, version, onUpgradeNeeded) {
return new Promise((resolve, reject) => {
const request = indexedDB.open(name, version);
request.onupgradeneeded = (event) => {
try {
request.transaction.onerror = (e) => reject(e.target.error);
onUpgradeNeeded(request.result, request.transaction, event.oldVersion, event.newVersion);
} catch (e) {
reject(e);
}
};
request.onerror = (e) => reject(e.target.error);
request.onsuccess = () => resolve(request.result);
});
}
_upgrade(db, transaction, oldVersion, upgrades) {
for (const {version, stores} of upgrades) {
if (oldVersion >= version) { continue; }
for (const [objectStoreName, {primaryKey, indices}] of Object.entries(stores)) {
const existingObjectStoreNames = transaction.objectStoreNames || db.objectStoreNames;
const objectStore = (
this._listContains(existingObjectStoreNames, objectStoreName) ?
transaction.objectStore(objectStoreName) :
db.createObjectStore(objectStoreName, primaryKey)
);
const existingIndexNames = objectStore.indexNames;
for (const indexName of indices) {
if (this._listContains(existingIndexNames, indexName)) { continue; }
objectStore.createIndex(indexName, indexName, {});
}
}
}
}
_listContains(list, value) {
for (let i = 0, ii = list.length; i < ii; ++i) {
if (list[i] === value) { return true; }
}
return false;
}
_getAllFast(objectStoreOrIndex, query, resolve, reject) {
const request = objectStoreOrIndex.getAll(query);
request.onerror = (e) => reject(e.target.error);
request.onsuccess = (e) => resolve(e.target.result);
}
_getAllUsingCursor(objectStoreOrIndex, query, resolve, reject) {
const results = [];
const request = objectStoreOrIndex.openCursor(query, 'next');
request.onerror = (e) => reject(e.target.error);
request.onsuccess = (e) => {
const cursor = e.target.result;
if (cursor) {
results.push(cursor.value);
cursor.continue();
} else {
resolve(results);
}
};
}
_getAllKeysFast(objectStoreOrIndex, query, resolve, reject) {
const request = objectStoreOrIndex.getAllKeys(query);
request.onerror = (e) => reject(e.target.error);
request.onsuccess = (e) => resolve(e.target.result);
}
_getAllKeysUsingCursor(objectStoreOrIndex, query, resolve, reject) {
const results = [];
const request = objectStoreOrIndex.openKeyCursor(query, 'next');
request.onerror = (e) => reject(e.target.error);
request.onsuccess = (e) => {
const cursor = e.target.result;
if (cursor) {
results.push(cursor.primaryKey);
cursor.continue();
} else {
resolve(results);
}
};
}
_bulkDeleteInternal(objectStore, keys, onProgress, resolve, reject) {
const count = keys.length;
if (count === 0) {
resolve();
return;
}
let completedCount = 0;
const hasProgress = (typeof onProgress === 'function');
const onError = (e) => reject(e.target.error);
const onSuccess = () => {
++completedCount;
if (hasProgress) {
try {
onProgress(completedCount, count);
} catch (e) {
// NOP
}
}
if (completedCount >= count) {
resolve();
}
};
for (const key of keys) {
const request = objectStore.delete(key);
request.onerror = onError;
request.onsuccess = onSuccess;
}
}
}