Recreate sliding window sample in typescript. Based on Go/Java/Python samples (#452)

billrich2001 · chris-olszewski · web-flow · commit a8a6d95e43ae · 2026-03-11T10:26:52.000-06:00
* Recreate sliding window sample in typescript. Based on Go/Java/Python samples

* Fix CI/linter issues

* Apply suggestions from code review

Co-authored-by: Chris Olszewski &lt;chrisdolszewski@gmail.com&gt;

* fix typo, change SingleRecord type to be imported explicitly

---------

Co-authored-by: Chris Olszewski &lt;chrisdolszewski@gmail.com&gt;
diff --git a/.scripts/list-of-samples.json b/.scripts/list-of-samples.json
@@ -4,6 +4,7 @@
     "activities-dependency-injection",
     "activities-examples",
     "ai-sdk",
+    "batch-sliding-window",
     "child-workflows",
     "continue-as-new",
     "cron-workflows",
diff --git a/batch-sliding-window/.eslintignore b/batch-sliding-window/.eslintignore
@@ -0,0 +1,3 @@
+node_modules
+lib
+.eslintrc.js
diff --git a/batch-sliding-window/.eslintrc.js b/batch-sliding-window/.eslintrc.js
@@ -0,0 +1,48 @@
+const { builtinModules } = require('module');
+
+const ALLOWED_NODE_BUILTINS = new Set(['assert']);
+
+module.exports = {
+  root: true,
+  parser: '@typescript-eslint/parser',
+  parserOptions: {
+    project: './tsconfig.json',
+    tsconfigRootDir: __dirname,
+  },
+  plugins: ['@typescript-eslint', 'deprecation'],
+  extends: [
+    'eslint:recommended',
+    'plugin:@typescript-eslint/eslint-recommended',
+    'plugin:@typescript-eslint/recommended',
+    'prettier',
+  ],
+  rules: {
+    // recommended for safety
+    '@typescript-eslint/no-floating-promises': 'error', // forgetting to await Activities and Workflow APIs is bad
+    'deprecation/deprecation': 'warn',
+
+    // code style preference
+    'object-shorthand': ['error', 'always'],
+
+    // relaxed rules, for convenience
+    '@typescript-eslint/no-unused-vars': [
+      'warn',
+      {
+        argsIgnorePattern: '^_',
+        varsIgnorePattern: '^_',
+      },
+    ],
+    '@typescript-eslint/no-explicit-any': 'off',
+  },
+  overrides: [
+    {
+      files: ['src/workflows.ts', 'src/workflows-*.ts', 'src/workflows/*.ts'],
+      rules: {
+        'no-restricted-imports': [
+          'error',
+          ...builtinModules.filter((m) => !ALLOWED_NODE_BUILTINS.has(m)).flatMap((m) => [m, `node:${m}`]),
+        ],
+      },
+    },
+  ],
+};
diff --git a/batch-sliding-window/.gitignore b/batch-sliding-window/.gitignore
@@ -0,0 +1,2 @@
+lib
+node_modules
diff --git a/batch-sliding-window/.npmrc b/batch-sliding-window/.npmrc
@@ -0,0 +1 @@
+package-lock=false
diff --git a/batch-sliding-window/.nvmrc b/batch-sliding-window/.nvmrc
@@ -0,0 +1 @@
+22
diff --git a/batch-sliding-window/.post-create b/batch-sliding-window/.post-create
@@ -0,0 +1,18 @@
+To begin development, install the Temporal CLI:
+
+Mac: {cyan brew install temporal}
+Other: Download and extract the latest release from https://github.com/temporalio/cli/releases/latest
+
+Start Temporal Server:
+
+{cyan temporal server start-dev}
+
+Use Node version 18+ (v22.x is recommended):
+
+Mac: {cyan brew install node@22}
+Other: https://nodejs.org/en/download/
+
+Then, in the project directory, using two other shells, run these commands:
+
+{cyan npm run start.watch}
+{cyan npm run workflow}
diff --git a/batch-sliding-window/.prettierignore b/batch-sliding-window/.prettierignore
@@ -0,0 +1 @@
+lib
diff --git a/batch-sliding-window/.prettierrc b/batch-sliding-window/.prettierrc
@@ -0,0 +1,2 @@
+printWidth: 120
+singleQuote: true
diff --git a/batch-sliding-window/README.md b/batch-sliding-window/README.md
@@ -0,0 +1,18 @@
+# Batch Sliding Window
+
+This sample demonstrates a batch processing workflow that maintains a sliding window of record processing workflows.
+
+A `SlidingWindowWorkflow` starts a configured number (sliding window size) of `RecordProcessorWorkflow` children in parallel. Each child processes a single record. When a child completes, a new child is started.
+
+The `SlidingWindowWorkflow` calls continue-as-new after starting a preconfigured number of children to keep its history size bounded. A `RecordProcessorWorkflow` reports its completion through a signal to its parent, which allows notification of a parent that called continue-as-new.
+
+A single instance of `SlidingWindowWorkflow` has limited window size and throughput. To support larger window size and overall throughput, multiple instances of `SlidingWindowWorkflow` run in parallel.
+
+### Running this sample
+
+1. `temporal server start-dev` to start [Temporal Server](https://github.com/temporalio/cli/#installation).
+2. `npm install` to install dependencies.
+3. `npm run start.watch` to start the Worker.
+4. In another shell, `npm run workflow` to run the Workflow.
+
+The workflow will process 90 records using a sliding window of 10 parallel workers across 3 partitions, with a page size of 5 records per continue-as-new iteration.
diff --git a/batch-sliding-window/package.json b/batch-sliding-window/package.json
@@ -0,0 +1,44 @@
+{
+  "name": "batch-sliding-window",
+  "version": "0.1.0",
+  "private": true,
+  "scripts": {
+    "build": "tsc --build",
+    "build.watch": "tsc --build --watch",
+    "format": "prettier --write .",
+    "format:check": "prettier --check .",
+    "lint": "eslint .",
+    "start": "ts-node src/worker.ts",
+    "start.watch": "nodemon src/worker.ts",
+    "workflow": "ts-node src/client.ts"
+  },
+  "nodemonConfig": {
+    "execMap": {
+      "ts": "ts-node"
+    },
+    "ext": "ts",
+    "watch": [
+      "src"
+    ]
+  },
+  "dependencies": {
+    "@temporalio/activity": "^1.15.0",
+    "@temporalio/client": "^1.15.0",
+    "@temporalio/envconfig": "^1.15.0",
+    "@temporalio/worker": "^1.15.0",
+    "@temporalio/workflow": "^1.15.0"
+  },
+  "devDependencies": {
+    "@tsconfig/node22": "^22.0.0",
+    "@types/node": "^22.9.1",
+    "@typescript-eslint/eslint-plugin": "^8.18.0",
+    "@typescript-eslint/parser": "^8.18.0",
+    "eslint": "^8.57.1",
+    "eslint-config-prettier": "^9.1.0",
+    "eslint-plugin-deprecation": "^3.0.0",
+    "nodemon": "^3.1.7",
+    "prettier": "^3.4.2",
+    "ts-node": "^10.9.2",
+    "typescript": "^5.6.3"
+  }
+}
diff --git a/batch-sliding-window/src/activities.ts b/batch-sliding-window/src/activities.ts
@@ -0,0 +1,38 @@
+export interface SingleRecord {
+  id: number;
+}
+
+export interface GetRecordsInput {
+  pageSize: number;
+  offset: number;
+  maxOffset: number;
+}
+
+export interface GetRecordsOutput {
+  records: SingleRecord[];
+}
+
+/**
+ * Factory that creates record-loader activities with a fixed total record count.
+ * The sample returns fake records; a real application would load from a database
+ * or other external data source.
+ */
+export function createActivities(recordCount: number) {
+  return {
+    async getRecordCount(): Promise<number> {
+      return recordCount;
+    },
+
+    async getRecords(input: GetRecordsInput): Promise<GetRecordsOutput> {
+      if (input.maxOffset > recordCount) {
+        throw new Error(`maxOffset(${input.maxOffset}) > recordCount(${recordCount})`);
+      }
+      const limit = Math.min(input.offset + input.pageSize, input.maxOffset);
+      const records: SingleRecord[] = [];
+      for (let i = input.offset; i < limit; i++) {
+        records.push({ id: i });
+      }
+      return { records };
+    },
+  };
+}
diff --git a/batch-sliding-window/src/client.ts b/batch-sliding-window/src/client.ts
@@ -0,0 +1,26 @@
+import { Client, Connection } from '@temporalio/client';
+import { loadClientConnectConfig } from '@temporalio/envconfig';
+import { processBatchWorkflow } from './workflows';
+
+async function run() {
+  const config = loadClientConnectConfig();
+  const connection = await Connection.connect(config.connectionOptions);
+  const client = new Client({ connection });
+
+  const workflowId = `batch-sliding-window-${Date.now()}`;
+
+  console.log(`Starting workflow ${workflowId}`);
+
+  const result = await client.workflow.execute(processBatchWorkflow, {
+    taskQueue: 'batch-sliding-window',
+    workflowId,
+    args: [{ pageSize: 5, slidingWindowSize: 10, partitions: 3 }],
+  });
+
+  console.log(`Workflow completed. Total records processed: ${result}`);
+}
+
+run().catch((err) => {
+  console.error(err);
+  process.exit(1);
+});
diff --git a/batch-sliding-window/src/worker.ts b/batch-sliding-window/src/worker.ts
@@ -0,0 +1,19 @@
+import { Worker } from '@temporalio/worker';
+import { createActivities } from './activities';
+
+async function run() {
+  const activities = createActivities(90);
+
+  const worker = await Worker.create({
+    workflowsPath: require.resolve('./workflows'),
+    activities,
+    taskQueue: 'batch-sliding-window',
+  });
+
+  await worker.run();
+}
+
+run().catch((err) => {
+  console.error(err);
+  process.exit(1);
+});
diff --git a/batch-sliding-window/src/workflows.ts b/batch-sliding-window/src/workflows.ts
diff --git a/batch-sliding-window/tsconfig.json b/batch-sliding-window/tsconfig.json
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml

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	`1`	`+node_modules`
	`2`	`+lib`
	`3`	`+.eslintrc.js`
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