trilium/src/becca/entities/abstract_becca_entity.ts
2024-02-18 20:41:30 +02:00

329 lines
12 KiB
TypeScript

"use strict";
import utils = require('../../services/utils');
import sql = require('../../services/sql');
import entityChangesService = require('../../services/entity_changes');
import eventService = require('../../services/events');
import dateUtils = require('../../services/date_utils');
import cls = require('../../services/cls');
import log = require('../../services/log');
import protectedSessionService = require('../../services/protected_session');
import blobService = require('../../services/blob');
import Becca = require('../becca-interface');
let becca: Becca | null = null;
interface ContentOpts {
forceSave?: boolean;
forceFrontendReload?: boolean;
}
interface ConstructorData<T extends AbstractBeccaEntity<T>> {
primaryKeyName: string;
entityName: string;
hashedProperties: (keyof T)[];
}
/**
* Base class for all backend entities.
*/
abstract class AbstractBeccaEntity<T extends AbstractBeccaEntity<T>> {
protected utcDateModified?: string;
protected dateCreated?: string;
protected dateModified?: string;
protected isSynced?: boolean;
protected blobId?: string;
utcDateCreated!: string;
isProtected?: boolean;
protected beforeSaving() {
const constructorData = (this.constructor as unknown as ConstructorData<T>);
if (!(this as any)[constructorData.primaryKeyName]) {
(this as any)[constructorData.primaryKeyName] = utils.newEntityId();
}
}
protected getUtcDateChanged() {
return this.utcDateModified || this.utcDateCreated;
}
protected get becca(): Becca {
if (!becca) {
becca = require('../becca');
}
return becca as Becca;
}
protected putEntityChange(isDeleted: boolean) {
const constructorData = (this.constructor as unknown as ConstructorData<T>);
entityChangesService.putEntityChange({
entityName: constructorData.entityName,
entityId: (this as any)[constructorData.primaryKeyName],
hash: this.generateHash(isDeleted),
isErased: false,
utcDateChanged: this.getUtcDateChanged(),
isSynced: constructorData.entityName !== 'options' || !!this.isSynced
});
}
protected generateHash(isDeleted: boolean): string {
const constructorData = (this.constructor as unknown as ConstructorData<T>);
let contentToHash = "";
for (const propertyName of constructorData.hashedProperties) {
contentToHash += `|${(this as any)[propertyName]}`;
}
if (isDeleted) {
contentToHash += "|deleted";
}
return utils.hash(contentToHash).substr(0, 10);
}
protected getPojoToSave() {
return this.getPojo();
}
hasStringContent(): boolean {
// TODO: Not sure why some entities don't implement it.
return true;
}
abstract getPojo(): {};
get isDeleted(): boolean {
// TODO: Not sure why some entities don't implement it.
return false;
}
/**
* Saves entity - executes SQL, but doesn't commit the transaction on its own
*/
// TODO: opts not used but called a few times, maybe should be used by derived classes or passed to beforeSaving.
save(opts?: {}): this {
const constructorData = (this.constructor as unknown as ConstructorData<T>);
const entityName = constructorData.entityName;
const primaryKeyName = constructorData.primaryKeyName;
const isNewEntity = !(this as any)[primaryKeyName];
this.beforeSaving();
const pojo = this.getPojoToSave();
sql.transactional(() => {
sql.upsert(entityName, primaryKeyName, pojo);
if (entityName === 'recent_notes') {
return;
}
this.putEntityChange(!!this.isDeleted);
if (!cls.isEntityEventsDisabled()) {
const eventPayload = {
entityName,
entity: this
};
if (isNewEntity) {
eventService.emit(eventService.ENTITY_CREATED, eventPayload);
}
eventService.emit(eventService.ENTITY_CHANGED, eventPayload);
}
});
return this;
}
protected _setContent(content: string | Buffer, opts: ContentOpts = {}) {
// client code asks to save entity even if blobId didn't change (something else was changed)
opts.forceSave = !!opts.forceSave;
opts.forceFrontendReload = !!opts.forceFrontendReload;
if (content === null || content === undefined) {
const constructorData = (this.constructor as unknown as ConstructorData<T>);
throw new Error(`Cannot set null content to ${constructorData.primaryKeyName} '${(this as any)[constructorData.primaryKeyName]}'`);
}
if (this.hasStringContent()) {
content = content.toString();
} else {
content = Buffer.isBuffer(content) ? content : Buffer.from(content);
}
const unencryptedContentForHashCalculation = this.getUnencryptedContentForHashCalculation(content);
if (this.isProtected) {
if (protectedSessionService.isProtectedSessionAvailable()) {
const encryptedContent = protectedSessionService.encrypt(content);
if (!encryptedContent) {
throw new Error(`Unable to encrypt the content of the entity.`);
}
content = encryptedContent;
} else {
throw new Error(`Cannot update content of blob since protected session is not available.`);
}
}
sql.transactional(() => {
const newBlobId = this.saveBlob(content, unencryptedContentForHashCalculation, opts);
const oldBlobId = this.blobId;
if (newBlobId !== oldBlobId || opts.forceSave) {
this.blobId = newBlobId;
this.save();
if (oldBlobId && newBlobId !== oldBlobId) {
this.deleteBlobIfNotUsed(oldBlobId);
}
}
});
}
private deleteBlobIfNotUsed(oldBlobId: string) {
if (sql.getValue("SELECT 1 FROM notes WHERE blobId = ? LIMIT 1", [oldBlobId])) {
return;
}
if (sql.getValue("SELECT 1 FROM attachments WHERE blobId = ? LIMIT 1", [oldBlobId])) {
return;
}
if (sql.getValue("SELECT 1 FROM revisions WHERE blobId = ? LIMIT 1", [oldBlobId])) {
return;
}
sql.execute("DELETE FROM blobs WHERE blobId = ?", [oldBlobId]);
// blobs are not marked as erased in entity_changes, they are just purged completely
// this is because technically every keystroke can create a new blob, and there would be just too many
sql.execute("DELETE FROM entity_changes WHERE entityName = 'blobs' AND entityId = ?", [oldBlobId]);
}
private getUnencryptedContentForHashCalculation(unencryptedContent: Buffer | string) {
if (this.isProtected) {
// a "random" prefix makes sure that the calculated hash/blobId is different for a decrypted/encrypted content
const encryptedPrefixSuffix = "t$[nvQg7q)&_ENCRYPTED_?M:Bf&j3jr_";
return Buffer.isBuffer(unencryptedContent)
? Buffer.concat([Buffer.from(encryptedPrefixSuffix), unencryptedContent])
: `${encryptedPrefixSuffix}${unencryptedContent}`;
} else {
return unencryptedContent;
}
}
private saveBlob(content: string | Buffer, unencryptedContentForHashCalculation: string | Buffer, opts: ContentOpts = {}) {
/*
* We're using the unencrypted blob for the hash calculation, because otherwise the random IV would
* cause every content blob to be unique which would balloon the database size (esp. with revisioning).
* This has minor security implications (it's easy to infer that given content is shared between different
* notes/attachments), but the trade-off comes out clearly positive.
*/
const newBlobId = utils.hashedBlobId(unencryptedContentForHashCalculation);
const blobNeedsInsert = !sql.getValue('SELECT 1 FROM blobs WHERE blobId = ?', [newBlobId]);
if (!blobNeedsInsert) {
return newBlobId;
}
const pojo = {
blobId: newBlobId,
content: content,
dateModified: dateUtils.localNowDateTime(),
utcDateModified: dateUtils.utcNowDateTime()
};
sql.upsert("blobs", "blobId", pojo);
// we can't reuse blobId as an entity_changes hash, because this one has to be calculatable without having
// access to the decrypted content
const hash = blobService.calculateContentHash(pojo);
entityChangesService.putEntityChange({
entityName: 'blobs',
entityId: newBlobId,
hash: hash,
isErased: false,
utcDateChanged: pojo.utcDateModified,
isSynced: true,
// overriding componentId will cause the frontend to think the change is coming from a different component
// and thus reload
componentId: opts.forceFrontendReload ? utils.randomString(10) : null
});
eventService.emit(eventService.ENTITY_CHANGED, {
entityName: 'blobs',
entity: this
});
return newBlobId;
}
protected _getContent(): string | Buffer {
const row = sql.getRow<{ content: string | Buffer }>(`SELECT content FROM blobs WHERE blobId = ?`, [this.blobId]);
if (!row) {
const constructorData = (this.constructor as unknown as ConstructorData<T>);
throw new Error(`Cannot find content for ${constructorData.primaryKeyName} '${(this as any)[constructorData.primaryKeyName]}', blobId '${this.blobId}'`);
}
return blobService.processContent(row.content, this.isProtected || false, this.hasStringContent());
}
/**
* Mark the entity as (soft) deleted. It will be completely erased later.
*
* This is a low-level method, for notes and branches use `note.deleteNote()` and 'branch.deleteBranch()` instead.
*/
markAsDeleted(deleteId: string | null = null) {
const constructorData = (this.constructor as unknown as ConstructorData<T>);
const entityId = (this as any)[constructorData.primaryKeyName];
const entityName = constructorData.entityName;
this.utcDateModified = dateUtils.utcNowDateTime();
sql.execute(`UPDATE ${entityName} SET isDeleted = 1, deleteId = ?, utcDateModified = ?
WHERE ${constructorData.primaryKeyName} = ?`,
[deleteId, this.utcDateModified, entityId]);
if (this.dateModified) {
this.dateModified = dateUtils.localNowDateTime();
sql.execute(`UPDATE ${entityName} SET dateModified = ? WHERE ${constructorData.primaryKeyName} = ?`,
[this.dateModified, entityId]);
}
log.info(`Marking ${entityName} ${entityId} as deleted`);
this.putEntityChange(true);
eventService.emit(eventService.ENTITY_DELETED, { entityName, entityId, entity: this });
}
markAsDeletedSimple() {
const constructorData = (this.constructor as unknown as ConstructorData<T>);
const entityId = (this as any)[constructorData.primaryKeyName];
const entityName = constructorData.entityName;
this.utcDateModified = dateUtils.utcNowDateTime();
sql.execute(`UPDATE ${entityName} SET isDeleted = 1, utcDateModified = ?
WHERE ${constructorData.primaryKeyName} = ?`,
[this.utcDateModified, entityId]);
log.info(`Marking ${entityName} ${entityId} as deleted`);
this.putEntityChange(true);
eventService.emit(eventService.ENTITY_DELETED, { entityName, entityId, entity: this });
}
}
export = AbstractBeccaEntity;