node-red-pulsar

Add Apache Pulsar support to Node-RED.

This package provides nodes to send and receive messages from Apache Pulsar in your Node-RED flows.

Table of Contents

• Features
• Requirements
• Installation
• Quick Start
• Nodes
  • Pulsar Client
  • Pulsar Authentication
  • Pulsar Schema
  • Pulsar Producer
  • Pulsar Consumer
  • Pulsar Reader
• Example Flow
• Development
• Contributing
• License

Features

• Producer: Send messages to Pulsar topics with configurable routing, batching, and compression
• Consumer: Subscribe to topics with shared, exclusive, or failover subscription modes
• Reader: Read messages from topics with seek support (earliest, latest, or timestamp)
• Schema Support: Avro and JSON schema validation
• Authentication: Token, OAuth2, and TLS certificate authentication
• TLS: Secure connections with certificate validation

Based on the Pulsar Node.js client.

Requirements

• Node.js >= 18.0.0
• Node-RED >= 3.0.0
• Apache Pulsar cluster (standalone or distributed)

Installation

Run the following command in your Node-RED user directory (typically ~/.node-red):

npm install @ng-galien/node-red-pulsar

Or install via the Node-RED Palette Manager by searching for @ng-galien/node-red-pulsar.

Quick Start

1. Start a Pulsar instance (for testing):

docker run -it -p 6650:6650 -p 8080:8080 apachepulsar/pulsar:3.0.2 bin/pulsar standalone

2. Configure the Pulsar Client node with pulsar://localhost:6650

3. Add a Producer node to send messages to a topic

4. Add a Consumer node to receive messages from the topic

Nodes

Pulsar Client

Configuration node for Pulsar connection settings.

Property	Description
Service URL	Pulsar broker URL (e.g., pulsar://localhost:6650)
Authentication	Optional authentication configuration
Use TLS	Enable TLS encryption
Operation Timeout	Timeout for operations in seconds

Pulsar Authentication

Configuration node for authentication methods.

Method	Description
Token	JWT token authentication
OAuth2	OAuth 2.0 client credentials flow
TLS	Client certificate authentication

Pulsar Schema

Configuration node for message schemas.

Type	Description
JSON	JSON schema validation
Avro	Avro schema validation

Pulsar Producer

Send messages to a Pulsar topic.

Input: msg.payload - Message content to send

Output: Status messages (sent, error)

Property	Description
Topic	Target topic name
Compression	Compression type (None, LZ4, ZLIB, ZSTD, SNAPPY)
Batching	Enable message batching

Pulsar Consumer

Receive messages from a Pulsar topic subscription.

Output 1: Received messages (msg.payload)

Output 2: Status messages

Property	Description
Topic	Topic to subscribe
Subscription	Subscription name
Subscription Type	Shared, Exclusive, Failover, or Key_Shared

Pulsar Reader

Read messages from a topic with seek capability.

Input: Seek commands (msg.topic = "seek", msg.payload = "Earliest" | "Latest" | timestamp)

Output 1: Read messages

Output 2: Status messages

Property	Description
Topic	Topic to read
Start Position	Initial position (Earliest, Latest)

Example Flow

A sample flow is provided in examples/pulsar-nodes.json. Import it into Node-RED to get started.

The example demonstrates:

• Sending string and JSON messages with a Producer
• Receiving messages with a Consumer using JSON schema
• Reading messages with a Reader and seek operations

Development

Setup

git clone https://github.com/ng-galien/node-red-contrib-pulsar.git
cd node-red-contrib-pulsar
npm install

Commands

npm run build       # Compile TypeScript
npm run lint        # Run ESLint
npm test            # Run tests
npm run clean       # Remove build artifacts

Testing with Docker

See CLAUDE.md for detailed E2E testing instructions with Docker.

Contributing

Contributions are welcome! Please read our Contributing Guide for details on:

• Code of Conduct
• Development setup
• Submitting pull requests
• Reporting issues

License

ISC - Copyright (c) Alexandre Boyer