UBERF-8899: Fix Reconnect performance (#7597)

Signed-off-by: Andrey Sobolev <haiodo@gmail.com>

server/core/src/types.ts

@@ -162,6 +162,11 @@ export interface DBAdapterManager {
 
 export interface PipelineContext {
   workspace: WorkspaceIdWithUrl
+
+  lastTx?: string
+
+  lastHash?: string
+
   hierarchy: Hierarchy
   modelDb: ModelDb
   branding: Branding | null

server/middleware/src/model.ts

@@ -115,6 +115,7 @@ export class ModelMiddleware extends BaseMiddleware implements Middleware {
 
   private setLastHash (hash: string): void {
     this.lastHash = hash
+    this.context.lastHash = this.lastHash
     this.lastHashResponse = Promise.resolve({
       full: false,
       hash,

server/middleware/src/txPush.ts

@@ -16,12 +16,16 @@
 import core, {
   DOMAIN_TRANSIENT,
   DOMAIN_TX,
+  generateId,
   TxProcessor,
+  WorkspaceEvent,
   type Doc,
   type MeasureContext,
+  type SessionData,
   type Tx,
   type TxCUD,
-  type TxResult
+  type TxResult,
+  type TxWorkspaceEvent
 } from '@hcengineering/core'
 import { PlatformError, unknownError } from '@hcengineering/platform'
 import type { DBAdapterManager, Middleware, PipelineContext, TxMiddlewareResult } from '@hcengineering/server-core'
@@ -68,6 +72,22 @@ export class TxMiddleware extends BaseMiddleware implements Middleware {
           txes: Array.from(new Set(txToStore.map((it) => it._class)))
         }
       )
+      // We need to remember last Tx Id in context, so it will be used during reconnect to track a requirement for refresh.
+      this.context.lastTx = txToStore[txToStore.length - 1]._id
+      // We need to deliver information to all clients so far.
+      const evt: TxWorkspaceEvent = {
+        _class: core.class.TxWorkspaceEvent,
+        _id: generateId(),
+        event: WorkspaceEvent.LastTx,
+        modifiedBy: core.account.System,
+        modifiedOn: Date.now(),
+        objectSpace: core.space.DerivedTx,
+        space: core.space.DerivedTx,
+        params: {
+          lastTx: this.context.lastTx
+        }
+      }
+      ;(ctx.contextData as SessionData).broadcast.txes.push(evt)
     }
     if (txPromise !== undefined) {
       await txPromise

server/rpc/src/rpc.ts

@@ -46,6 +46,8 @@ export interface HelloResponse extends Response<any> {
   binary: boolean
   reconnect?: boolean
   serverVersion: string
+  lastTx?: string
+  lastHash?: string // Last model hash
 }
 
 function replacer (key: string, value: any): any {

server/server/src/sessionManager.ts

@@ -990,7 +990,7 @@ class TSessionManager implements SessionManager {
           return
         }
         if (request.id === -1 && request.method === 'hello') {
-          this.handleHello<S>(request, service, ctx, workspace, ws, requestCtx)
+          await this.handleHello<S>(request, service, ctx, workspace, ws, requestCtx)
           return
         }
         if (request.id === -2 && request.method === 'forceClose') {
@@ -1053,14 +1053,14 @@ class TSessionManager implements SessionManager {
       })
   }
 
-  private handleHello<S extends Session>(
+  private async handleHello<S extends Session>(
     request: Request<any>,
     service: S,
     ctx: MeasureContext<any>,
     workspace: string,
     ws: ConnectionSocket,
     requestCtx: MeasureContext<any>
-  ): void {
+  ): Promise<void> {
     const hello = request as HelloRequest
     service.binaryMode = hello.binary ?? false
     service.useCompression = hello.compression ?? false
@@ -1080,12 +1080,16 @@ class TSessionManager implements SessionManager {
     if (reconnect) {
       this.reconnectIds.delete(service.sessionId)
     }
+    const pipeline =
+      service.workspace.pipeline instanceof Promise ? await service.workspace.pipeline : service.workspace.pipeline
     const helloResponse: HelloResponse = {
       id: -1,
       result: 'hello',
       binary: service.binaryMode,
       reconnect,
-      serverVersion: this.serverVersion
+      serverVersion: this.serverVersion,
+      lastTx: pipeline.context.lastTx,
+      lastHash: pipeline.context.lastHash
     }
     ws.send(requestCtx, helloResponse, false, false)
   }