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