feat(node): add node implementation

.gitattributes

@@ -0,0 +1 @@
+* text=auto eol=lf

.github/dependabot.yml

@@ -30,3 +30,12 @@ updates:
     groups:
       tooling:
         patterns: ["*"]
+
+  # Node runtime/dev dependencies in node/package.json.
+  - package-ecosystem: npm
+    directory: /node
+    schedule:
+      interval: weekly
+    groups:
+      node:
+        patterns: ["*"]

.github/workflows/node.yml

@@ -0,0 +1,78 @@
+name: Node CI
+
+# Path-filtered so the Node package is validated independently.
+on:
+  push:
+    branches:
+      - main
+      - "release-*"
+    paths:
+      - "node/**"
+      - ".github/workflows/node.yml"
+  pull_request:
+    paths:
+      - "node/**"
+      - ".github/workflows/node.yml"
+
+permissions:
+  contents: read
+
+jobs:
+  # Load the test matrix from package.json's supportedNodeVersions.
+  versions:
+    name: node versions
+    runs-on: ubuntu-latest
+    outputs:
+      data: ${{ steps.set.outputs.data }}
+    steps:
+      - name: Check out the repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Generate supported versions from package.json
+        id: set
+        working-directory: node
+        run: echo "data=$(npm run --silent list-supported-versions)" >> "$GITHUB_OUTPUT"
+
+  test:
+    name: Node ${{ matrix.node-version }} (${{ matrix.os }})
+    needs: versions
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+        node-version: ${{ fromJson(needs.versions.outputs.data).all }}
+    defaults:
+      run:
+        working-directory: node
+    steps:
+      - name: Check out the repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Set up Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@2028fbc5c25fe9cf00d9f06a71cc4710d4507903 # v6.0.0
+        with:
+          node-version: ${{ matrix.node-version }}
+          cache: npm
+          cache-dependency-path: node/package-lock.json
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Lint
+        run: npm run lint
+
+      - name: Check formatting
+        run: npm run format:check
+
+      - name: Typecheck
+        run: npm run typecheck
+
+      - name: Test
+        run: npm test
+
+      - name: Build
+        run: npm run build
+
+      - name: Validate package contents
+        run: npm pack --dry-run

.gitignore

@@ -4,5 +4,5 @@
 *.iml
 .vscode/
 
-# Language-specific ignores live in python/.gitignore and java/.gitignore so
+# Language-specific ignores live in python/.gitignore and node/.gitignore so
 # each package stays self-contained.

README.md

@@ -1,20 +1,24 @@
 # Developer Toolkit for ElastiCache
 
-This repository contains tools to work with [Amazon ElastiCache](https://aws.amazon.com/elasticache/).
+This repository contains libraries and tools for working with
+[Amazon ElastiCache](https://aws.amazon.com/elasticache/).
 
-The Python library offers [IAM authentication](https://docs.aws.amazon.com/AmazonElastiCache/latest/dg/auth-iam.html)
-for ElastiCache: generates a signed token that ElastiCache requires for connection
-with an IAM-enabled user, so applications can authenticate to a Valkey or
-Redis OSS cache with AWS credentials.
+The Python and Node.js libraries support
+[IAM authentication](https://docs.aws.amazon.com/AmazonElastiCache/latest/dg/auth-iam.html)
+for ElastiCache. They generate the signed token required to connect with an
+IAM-enabled user, allowing applications to authenticate to a Valkey or Redis OSS
+cache with AWS credentials.
 
 ## Packages
 
 | Language | Package | Documentation |
 |---|---|---|
 | Python | [`developer-toolkit-elasticache`](https://pypi.org/project/developer-toolkit-elasticache/) on PyPI | [python/README.md](python/README.md) |
+| Node.js | `@aws/developer-toolkit-elasticache` on npm | [node/README.md](node/README.md) |
 
+## Quick start
 
-## Quick start (Python)
+### Python
 
 ```bash
 python3 -m pip install developer-toolkit-elasticache
@@ -34,6 +38,26 @@ Use the returned token as the password when connecting to the cache. See the
 [Python README](python/README.md) for requirements, the credential chain, the Python
 command-line tool, and client integration examples.
 
+### Node.js
+
+```bash
+npm install @aws/developer-toolkit-elasticache
+```
+
+```typescript
+import { generateIamAuthToken } from "@aws/developer-toolkit-elasticache";
+
+const token = await generateIamAuthToken({
+  serverlessCacheName: "my-cache", // or replicationGroupId: "my-group"
+  userId: "iam-user",
+  region: "us-east-1",
+});
+```
+
+Use the returned token as the password when connecting to the cache. See the
+[Node.js README](node/README.md) for requirements, the credential and region
+chains, the async token provider, and client integration examples.
+
 ## Getting help
 
 Please use these community resources for getting help. We use the GitHub issues for

node/.gitignore

@@ -0,0 +1,14 @@
+# Build artifacts
+dist/
+dist-test/
+node_modules/
+
+# npm
+*.tgz
+npm-debug.log*
+
+# Test / coverage output
+coverage/
+
+# OS / editor
+.DS_Store

node/.prettierignore

@@ -0,0 +1,4 @@
+dist/
+dist-test/
+node_modules/
+package-lock.json

node/.prettierrc.json

@@ -0,0 +1,6 @@
+{
+  "printWidth": 90,
+  "proseWrap": "always",
+  "singleQuote": false,
+  "trailingComma": "all"
+}

node/CHANGELOG.md

@@ -0,0 +1,16 @@
+# Changelog
+
+All notable changes to the Node.js package are documented here. The format follows
+[Keep a Changelog](https://keepachangelog.com/en/1.1.0/) and the package uses
+[Semantic Versioning](https://semver.org/).
+
+## [Unreleased]
+
+### Added
+
+- `generateIamAuthToken()` for signing IAM authentication tokens for Amazon ElastiCache
+  serverless caches and node-based replication groups.
+- `ElastiCacheIAMAuthTokenProvider` for generating fresh tokens when clients connect or
+  reconnect.
+- `ToolkitInputError`, `InvalidParameterError`, and `ConfigurationError`.
+- Runnable token-generation and iovalkey integration examples under `examples/`.