feat(nbstore): new doc sync engine (#8918)

packages/common/nbstore/src/impls/idb/doc.ts

@@ -1,5 +1,6 @@
 import { share } from '../../connection';
 import {
+  type DocClock,
   type DocClocks,
   type DocRecord,
   DocStorage,
@@ -14,9 +15,20 @@ export class IndexedDBDocStorage extends DocStorage {
     return this.connection.inner;
   }
 
-  override async pushDocUpdate(update: DocUpdate) {
-    const trx = this.db.transaction(['updates', 'clocks'], 'readwrite');
+  private _lastTimestamp = new Date(0);
+
+  private generateTimestamp() {
     const timestamp = new Date();
+    if (timestamp.getTime() <= this._lastTimestamp.getTime()) {
+      timestamp.setTime(this._lastTimestamp.getTime() + 1);
+    }
+    this._lastTimestamp = timestamp;
+    return timestamp;
+  }
+
+  override async pushDocUpdate(update: DocUpdate, origin?: string) {
+    const trx = this.db.transaction(['updates', 'clocks'], 'readwrite');
+    const timestamp = this.generateTimestamp();
     await trx.objectStore('updates').add({
       ...update,
       createdAt: timestamp,
@@ -24,6 +36,17 @@ export class IndexedDBDocStorage extends DocStorage {
 
     await trx.objectStore('clocks').put({ docId: update.docId, timestamp });
 
+    this.emit(
+      'update',
+      {
+        docId: update.docId,
+        bin: update.bin,
+        timestamp,
+        editor: update.editor,
+      },
+      origin
+    );
+
     return { docId: update.docId, timestamp };
   }
 
@@ -72,6 +95,12 @@ export class IndexedDBDocStorage extends DocStorage {
     }, {} as DocClocks);
   }
 
+  override async getDocTimestamp(docId: string): Promise<DocClock | null> {
+    const trx = this.db.transaction('clocks', 'readonly');
+
+    return (await trx.store.get(docId)) ?? null;
+  }
+
   protected override async setDocSnapshot(
     snapshot: DocRecord
   ): Promise<boolean> {

packages/common/nbstore/src/impls/idb/schema.ts

@@ -94,6 +94,7 @@ export interface DocStorageSchema extends DBSchema {
       peer: string;
       docId: string;
       clock: Date;
+      pulledClock: Date;
       pushedClock: Date;
     };
     indexes: {

packages/common/nbstore/src/impls/idb/sync.ts

@@ -8,7 +8,7 @@ export class IndexedDBSyncStorage extends SyncStorage {
     return this.connection.inner;
   }
 
-  override async getPeerClocks(peer: string) {
+  override async getPeerRemoteClocks(peer: string) {
     const trx = this.db.transaction('peerClocks', 'readonly');
 
     const records = await trx.store.index('peer').getAll(peer);
@@ -19,7 +19,7 @@ export class IndexedDBSyncStorage extends SyncStorage {
     }, {} as DocClocks);
   }
 
-  override async setPeerClock(peer: string, clock: DocClock) {
+  override async setPeerRemoteClock(peer: string, clock: DocClock) {
     const trx = this.db.transaction('peerClocks', 'readwrite');
     const record = await trx.store.get([peer, clock.docId]);
 
@@ -28,6 +28,32 @@ export class IndexedDBSyncStorage extends SyncStorage {
         peer,
         docId: clock.docId,
         clock: clock.timestamp,
+        pulledClock: record?.pulledClock ?? new Date(0),
+        pushedClock: record?.pushedClock ?? new Date(0),
+      });
+    }
+  }
+
+  override async getPeerPulledRemoteClocks(peer: string) {
+    const trx = this.db.transaction('peerClocks', 'readonly');
+
+    const records = await trx.store.index('peer').getAll(peer);
+
+    return records.reduce((clocks, { docId, pulledClock }) => {
+      clocks[docId] = pulledClock;
+      return clocks;
+    }, {} as DocClocks);
+  }
+  override async setPeerPulledRemoteClock(peer: string, clock: DocClock) {
+    const trx = this.db.transaction('peerClocks', 'readwrite');
+    const record = await trx.store.get([peer, clock.docId]);
+
+    if (!record || record.pulledClock < clock.timestamp) {
+      await trx.store.put({
+        peer,
+        docId: clock.docId,
+        clock: record?.clock ?? new Date(0),
+        pulledClock: clock.timestamp,
         pushedClock: record?.pushedClock ?? new Date(0),
       });
     }
@@ -54,6 +80,7 @@ export class IndexedDBSyncStorage extends SyncStorage {
         docId: clock.docId,
         clock: record?.clock ?? new Date(0),
         pushedClock: clock.timestamp,
+        pulledClock: record?.pulledClock ?? new Date(0),
       });
     }
   }

packages/common/nbstore/src/impls/idb/v1/doc.ts

@@ -57,6 +57,10 @@ export class IndexedDBV1DocStorage extends DocStorage {
     return {};
   }
 
+  override async getDocTimestamp(_docId: string) {
+    return null;
+  }
+
   protected override async setDocSnapshot(): Promise<boolean> {
     return false;
   }