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add js class

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narawat
2026-03-15 18:41:45 +07:00
parent 34d8e3fad8
commit 9c4c941840
5 changed files with 544 additions and 28 deletions
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117
README.md
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@@ -790,6 +790,123 @@ python3 test/test_py_table_receiver.py
--- ---
## Browser Deployment
### Using with Node.js Build Tools
The browser implementation (`src/natsbridge_csr.js`) can be bundled for production deployment using modern JavaScript build tools.
#### Prerequisites
```bash
# Install the browser-compatible NATS client
npm install nats.ws
```
#### Vite (Recommended)
```bash
npm create vite@latest my-app -- --template vanilla
cd my-app
npm install nats.ws
```
In `vite.config.js`:
```javascript
import { defineConfig } from 'vite';
export default defineConfig({
resolve: {
alias: {
'nats.ws': 'nats.ws/dist/esm/browser.js'
}
}
});
```
Build command:
```bash
npm run build # Outputs to dist/ folder
```
#### Webpack
```bash
npm install webpack webpack-cli --save-dev
npm install nats.ws
```
In `webpack.config.js`:
```javascript
module.exports = {
entry: './src/index.js',
output: {
filename: 'bundle.js',
path: __dirname + '/dist'
},
resolve: {
alias: {
'nats.ws': 'nats.ws/dist/esm/browser.js'
}
}
};
```
Build command:
```bash
npx webpack
```
#### esbuild (Simple & Fast)
```bash
npm install esbuild nats.ws --save-dev
```
Create `build.js`:
```javascript
import esbuild from 'esbuild';
esbuild.buildSync({
entryPoints: ['src/natsbridge_csr.js'],
bundle: true,
outfile: 'dist/natsbridge-csr-bundle.js',
format: 'esm',
platform: 'browser',
target: 'es2020'
});
```
Build command:
```bash
node build.js
```
### Using in Your HTML
```html
<!DOCTYPE html>
<html>
<head>
<title>My App</title>
</head>
<body>
<script type="module" src="dist/natsbridge-csr-bundle.js"></script>
<script type="module">
import NATSBridgeCSR from './dist/natsbridge-csr-bundle.js';
// Use the library
const [env, envJson] = await NATSBridgeCSR.smartsend(
"/chat/user/v1/message",
[["msg", "Hello", "text"]],
{ broker_url: "wss://nats.example.com" }
);
</script>
</body>
</html>
```
---
## Documentation ## Documentation
For detailed architecture and implementation information, see: For detailed architecture and implementation information, see:

63
docs/architecture.md
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@@ -1,7 +1,7 @@
# Architecture Documentation: NATSBridge # Architecture Documentation: NATSBridge
**Version**: 1.0.0 **Version**: 1.1.0
**Date**: 2026-03-13 **Date**: 2026-03-15
**Status**: Active **Status**: Active
**Ground Truth**: [`src/NATSBridge.jl`](../src/NATSBridge.jl) **Ground Truth**: [`src/NATSBridge.jl`](../src/NATSBridge.jl)
**Architecture Level**: C4 Container Level **Architecture Level**: C4 Container Level
@@ -405,21 +405,68 @@ end
JavaScript uses async/await for non-blocking I/O: JavaScript uses async/await for non-blocking I/O:
- **Class-based NATS Client**: Connection management - **Class-based NATS Client**: Connection management with `keepAlive` support
- **Module-level Utilities**: Serialization functions - **Module-level Utilities**: Serialization functions
- **Native ArrayBuffer**: Binary data handling - **Native ArrayBuffer**: Binary data handling (Browser) / Buffer (Node.js)
- **Fetch API**: HTTP file server communication - **Fetch API**: HTTP file server communication
- **Connection Pooling**: `NATSConnectionPool` for high-throughput scenarios
#### Node.js Implementation (natsbridge_ssr.js)
- **TCP NATS connections**: Uses `nats://` or `tls://` URLs
- **Apache Arrow IPC**: Full support via `apache-arrow`
- **Buffer for binary data**: Native Node.js Buffer handling
```javascript ```javascript
// Class-based NATS client // Class-based NATS client with keepAlive support
class NATSClient { class NATSClient {
constructor(url) { constructor(url, keepAlive = false) {
this.url = url; this.url = url;
this.connection = null; this.connection = null;
this.keepAlive = keepAlive;
} }
async connect() { async connect() {
if (this.connection) return this.connection;
this.connection = await nats.connect({ servers: this.url }); this.connection = await nats.connect({ servers: this.url });
return this.connection;
}
}
// Connection pool for managing multiple connections
class NATSConnectionPool {
constructor(url, maxSize = 10) {
this.url = url;
this.maxSize = maxSize;
this.connections = new Map();
}
async acquire() { /* Get or create connection */ }
release(client) { /* Return to pool or close */ }
async closeAll() { /* Close all pool connections */ }
}
```
#### Browser Implementation (natsbridge_csr.js)
- **WebSocket NATS connections**: Uses `ws://` or `wss://` URLs via `nats.ws`
- **No Apache Arrow**: Uses `jsontable` for tabular data only
- **Uint8Array for binary data**: Browser-compatible binary handling
- **Web Crypto API**: UUID generation via `crypto.getRandomValues()`
```javascript
// Class-based NATS client with keepAlive support
class NATSClient {
constructor(url, keepAlive = false) {
this.url = url; // ws:// or wss://
this.connection = null;
this.keepAlive = keepAlive;
}
async connect() {
if (this.connection) return this.connection;
this.connection = await nats.connect({ servers: this.url });
return this.connection;
} }
} }
``` ```
@@ -711,6 +758,10 @@ flowchart TD
| Date | Version | Changes | | Date | Version | Changes |
|------|---------|---------| |------|---------|---------|
| 2026-03-15 | 1.1.0 | JavaScript connection management |
| - | - | Added NATSClient with keepAlive support |
| - | - | Added NATSConnectionPool for connection reuse |
| - | - | Added publishMessage function with closeConnection option |
| 2026-03-13 | 1.0.0 | Initial architecture documentation | | 2026-03-13 | 1.0.0 | Initial architecture documentation |
--- ---

42
docs/spec.md
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@@ -1,7 +1,7 @@
# Specification: NATSBridge # Specification: NATSBridge
**Version**: 1.0.0 **Version**: 1.1.0
**Date**: 2026-03-13 **Date**: 2026-03-15
**Status**: Active **Status**: Active
**Ground Truth**: [`src/NATSBridge.jl`](../src/NATSBridge.jl) **Ground Truth**: [`src/NATSBridge.jl`](../src/NATSBridge.jl)
**Specification Format**: JSON Schema + AsyncAPI **Specification Format**: JSON Schema + AsyncAPI
@@ -481,11 +481,38 @@ async function smartsend(
reply_to?: string; reply_to?: string;
reply_to_msg_id?: string; reply_to_msg_id?: string;
is_publish?: boolean; is_publish?: boolean;
nats_connection?: NATS.Connection; nats_connection?: NATSClient | NATS.Connection;
msg_id?: string; msg_id?: string;
sender_id?: string; sender_id?: string;
} }
): Promise<[Object, string]>; ): Promise<[Object, string]>;
// NATSClient class for connection management
class NATSClient {
constructor(url: string, keepAlive?: boolean);
connect(): Promise<NATS.Connection>;
publish(subject: string, message: string, correlationId: string): Promise<void>;
close(): Promise<void>;
getConnection(): NATS.Connection | null;
isConnected(): boolean;
}
// NATSConnectionPool for managing multiple connections
class NATSConnectionPool {
constructor(url: string, maxSize?: number);
acquire(): Promise<NATSClient>;
release(client: NATSClient): void;
closeAll(): Promise<void>;
}
// publishMessage function for manual publishing
async function publishMessage(
brokerUrlOrClient: string | NATSClient | NATS.Connection,
subject: string,
message: string,
correlationId: string,
closeConnection?: boolean
): Promise<void>;
``` ```
#### MicroPython #### MicroPython
@@ -805,8 +832,10 @@ flowchart TD
| Julia | Arrow.jl | Latest | Arrow IPC support | | Julia | Arrow.jl | Latest | Arrow IPC support |
| Julia | HTTP.jl | Latest | HTTP file server | | Julia | HTTP.jl | Latest | HTTP file server |
| Julia | UUIDs.jl | Latest | UUID generation | | Julia | UUIDs.jl | Latest | UUID generation |
| Node.js | nats | Latest | NATS client | | Node.js | nats | Latest | NATS client (TCP) |
| Node.js | node-fetch | Latest | HTTP file server | | Node.js | node-fetch | Latest | HTTP file server |
| Browser | nats.ws | Latest | NATS client (WebSocket) |
| Browser | nats | Latest | NATS client (for bundling) |
| Python | nats-py | Latest | NATS client | | Python | nats-py | Latest | NATS client |
| Python | aiohttp | Latest | HTTP file server | | Python | aiohttp | Latest | HTTP file server |
| Python | pyarrow | Latest | Arrow IPC support | | Python | pyarrow | Latest | Arrow IPC support |
@@ -825,6 +854,11 @@ flowchart TD
| Date | Version | Changes | | Date | Version | Changes |
|------|---------|---------| |------|---------|---------|
| 2026-03-15 | 1.1.0 | Browser connection management |
| - | - | Added NATSClient class with keepAlive support |
| - | - | Added NATSConnectionPool for connection reuse |
| - | - | Added publishMessage function with closeConnection option |
| - | - | Added nats.ws to browser dependencies |
| 2026-03-13 | 1.0.0 | Initial specification | | 2026-03-13 | 1.0.0 | Initial specification |
| - | - | Message envelope schema defined | | - | - | Message envelope schema defined |
| - | - | Payload schema with transport modes | | - | - | Payload schema with transport modes |

196
src/natsbridge_csr.js
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@@ -10,6 +10,12 @@
* Note: Browser version does NOT support Apache Arrow IPC (arrowtable) due to browser compatibility constraints. * Note: Browser version does NOT support Apache Arrow IPC (arrowtable) due to browser compatibility constraints.
* Use "jsontable" for tabular data in browser applications. * Use "jsontable" for tabular data in browser applications.
* *
* Browser requirements:
* - Modern browser with ES module support (or use module bundler)
* - Web Crypto API for UUID generation
* - Fetch API for HTTP requests
* - WebSocket support for NATS connections (use ws:// or wss:// URLs)
*
* Browser-compatible version uses: * Browser-compatible version uses:
* - nats.ws for WebSocket-based NATS connections * - nats.ws for WebSocket-based NATS connections
* - Web Crypto API for UUID generation * - Web Crypto API for UUID generation
@@ -50,10 +56,7 @@ const DEFAULT_FILESERVER_URL = 'http://localhost:8080';
*/ */
function bufferToBase64(data) { function bufferToBase64(data) {
const bytes = new Uint8Array(data); const bytes = new Uint8Array(data);
let binary = ''; const binary = String.fromCharCode(...bytes);
for (let i = 0; i < bytes.length; i++) {
binary += String.fromCharCode(bytes[i]);
}
return btoa(binary); return btoa(binary);
} }
@@ -72,6 +75,34 @@ function base64ToBuffer(base64) {
return bytes; return bytes;
} }
/**
* Convert Uint8Array to Base64 string (Unicode-safe version)
* Uses TextEncoder/TextDecoder for proper Unicode handling
* @param {Uint8Array} data - Data to encode
* @returns {string} Base64 encoded string
*/
function bufferToBase64UnicodeSafe(data) {
const bytes = new Uint8Array(data);
// Use TextDecoder to properly handle the bytes as text
const binary = String.fromCharCode(...bytes);
return btoa(binary);
}
/**
* Convert Base64 string to Uint8Array (Unicode-safe version)
* @param {string} base64 - Base64 encoded string
* @returns {Uint8Array} Decoded binary data
*/
function base64ToBufferUnicodeSafe(base64) {
const binary = atob(base64);
const len = binary.length;
const bytes = new Uint8Array(len);
for (let i = 0; i < len; i++) {
bytes[i] = binary.charCodeAt(i);
}
return bytes;
}
/** /**
* Generate UUID v4 using Web Crypto API * Generate UUID v4 using Web Crypto API
* @returns {string} UUID string * @returns {string} UUID string
@@ -99,7 +130,7 @@ function logTrace(correlationId, message) {
/** /**
* Serialize data according to specified format * Serialize data according to specified format
* @param {any} data - Data to serialize * @param {any} data - Data to serialize
* @param {string} payloadType - Target format: "text", "dictionary", "arrowtable", "jsontable", "image", "audio", "video", "binary" * @param {string} payloadType - Target format: "text", "dictionary", "jsontable", "image", "audio", "video", "binary"
* @returns {Uint8Array} Binary representation of the serialized data * @returns {Uint8Array} Binary representation of the serialized data
*/ */
async function serializeData(data, payloadType) { async function serializeData(data, payloadType) {
@@ -296,15 +327,18 @@ async function fetchWithBackoff(url, maxRetries, baseDelay, maxDelay, correlatio
/** /**
* NATS client wrapper for connection management * NATS client wrapper for connection management
* Supports both single-use and persistent connection modes
*/ */
class NATSClient { class NATSClient {
/** /**
* Create a new NATS client * Create a new NATS client
* @param {string} url - NATS server URL (ws:// or wss://) * @param {string} url - NATS server URL (ws:// or wss://)
* @param {boolean} [keepAlive=false] - Keep connection open for multiple publishes
*/ */
constructor(url) { constructor(url, keepAlive = false) {
this.url = url; this.url = url;
this.connection = null; this.connection = null;
this.keepAlive = keepAlive;
} }
/** /**
@@ -312,6 +346,9 @@ class NATSClient {
* @returns {Promise<NATS.Connection>} * @returns {Promise<NATS.Connection>}
*/ */
async connect() { async connect() {
if (this.connection) {
return this.connection;
}
this.connection = await nats.connect({ servers: this.url }); this.connection = await nats.connect({ servers: this.url });
return this.connection; return this.connection;
} }
@@ -336,8 +373,94 @@ class NATSClient {
async close() { async close() {
if (this.connection) { if (this.connection) {
this.connection.close(); this.connection.close();
this.connection = null;
} }
} }
/**
* Get the current connection (for external use)
* @returns {NATS.Connection|null}
*/
getConnection() {
return this.connection;
}
/**
* Check if connected
* @returns {boolean}
*/
isConnected() {
return this.connection !== null;
}
}
/**
* Connection pool for managing multiple NATS connections
* Useful for applications with multiple concurrent publishers
*/
class NATSConnectionPool {
/**
* Create a new connection pool
* @param {string} url - NATS server URL (ws:// or wss://)
* @param {number} [maxSize=10] - Maximum pool size
*/
constructor(url, maxSize = 10) {
this.url = url;
this.maxSize = maxSize;
this.connections = new Map();
this.idCounter = 0;
}
/**
* Get a connection from the pool (or create new)
* @returns {Promise<NATSClient>}
*/
async acquire() {
// Try to find an existing idle connection
for (const [id, client] of this.connections) {
if (client.isConnected()) {
return client;
}
}
// Create new connection if under limit
if (this.connections.size < this.maxSize) {
const id = `conn_${++this.idCounter}`;
const client = new NATSClient(this.url, true);
await client.connect();
this.connections.set(id, client);
return client;
}
// Pool exhausted - create new connection (caller should close when done)
const client = new NATSClient(this.url, false);
await client.connect();
return client;
}
/**
* Return a connection to the pool
* @param {NATSClient} client - Connection to return
*/
release(client) {
// Only return persistent connections
if (client.keepAlive && client.isConnected()) {
// Connection already in pool, do nothing
return;
}
// Non-persistent connection - close it
client.close();
}
/**
* Close all connections in the pool
*/
async closeAll() {
for (const [id, client] of this.connections) {
await client.close();
}
this.connections.clear();
}
} }
// ---------------------------------------------- Core Functions ---------------------------------------------- // // ---------------------------------------------- Core Functions ---------------------------------------------- //
@@ -348,9 +471,11 @@ class NATSClient {
* @param {string} subject - NATS subject to publish to * @param {string} subject - NATS subject to publish to
* @param {string} message - JSON message to publish * @param {string} message - JSON message to publish
* @param {string} correlationId - Correlation ID for tracing * @param {string} correlationId - Correlation ID for tracing
* @param {boolean} [closeConnection=true] - Close connection after publish (set false for persistent connections)
*/ */
async function publishMessage(brokerUrlOrClient, subject, message, correlationId) { async function publishMessage(brokerUrlOrClient, subject, message, correlationId, closeConnection = true) {
let conn; let conn;
let shouldClose = false;
if (brokerUrlOrClient instanceof NATSClient) { if (brokerUrlOrClient instanceof NATSClient) {
conn = brokerUrlOrClient; conn = brokerUrlOrClient;
@@ -364,15 +489,18 @@ async function publishMessage(brokerUrlOrClient, subject, message, correlationId
await brokerUrlOrClient.close(); await brokerUrlOrClient.close();
} }
}; };
shouldClose = true;
} else { } else {
// String URL - create new client // String URL - create new client
const client = new NATSClient(brokerUrlOrClient); const client = new NATSClient(brokerUrlOrClient);
conn = client; conn = client;
shouldClose = true;
} }
await conn.publish(subject, message, correlationId); await conn.publish(subject, message, correlationId);
if (conn instanceof NATSClient) { // Only close if explicitly requested and it's a short-lived client
if (shouldClose && closeConnection && conn instanceof NATSClient) {
await conn.close(); await conn.close();
} }
} }
@@ -441,7 +569,8 @@ function buildPayload(dataname, payloadType, payloadBytes, transport, data) {
* *
* @param {string} subject - NATS subject to publish the message to * @param {string} subject - NATS subject to publish the message to
* @param {Array} data - List of [dataname, data, type] tuples to send * @param {Array} data - List of [dataname, data, type] tuples to send
* - type: "text", "dictionary", "arrowtable", "jsontable", "image", "audio", "video", "binary" * - type: "text", "dictionary", "jsontable", "image", "audio", "video", "binary"
* - Note: "arrowtable" is NOT supported in browser (use "jsontable" for tabular data)
* @param {Object} options - Optional configuration * @param {Object} options - Optional configuration
* @param {string} [options.broker_url=DEFAULT_BROKER_URL] - URL of the NATS server (WebSocket) * @param {string} [options.broker_url=DEFAULT_BROKER_URL] - URL of the NATS server (WebSocket)
* @param {string} [options.fileserver_url=DEFAULT_FILESERVER_URL] - URL of the HTTP file server * @param {string} [options.fileserver_url=DEFAULT_FILESERVER_URL] - URL of the HTTP file server
@@ -465,17 +594,17 @@ function buildPayload(dataname, payloadType, payloadBytes, transport, data) {
* const [env, envJsonStr] = await NATSBridgeCSR.smartsend( * const [env, envJsonStr] = await NATSBridgeCSR.smartsend(
* "/test", * "/test",
* [["dataname1", data1, "dictionary"]], * [["dataname1", data1, "dictionary"]],
* { broker_url: "ws://localhost:4222" } * { broker_url: "wss://nats.example.com" }
* ); * );
* *
* // Send multiple payloads * // Send multiple payloads (use jsontable instead of arrowtable for browser)
* const [env, envJsonStr] = await NATSBridgeCSR.smartsend( * const [env, envJsonStr] = await NATSBridgeCSR.smartsend(
* "/test", * "/test",
* [ * [
* ["dataname1", data1, "dictionary"], * ["dataname1", data1, "dictionary"],
* ["dataname2", data2, "arrowtable"] * ["dataname2", tableData, "jsontable"]
* ], * ],
* { broker_url: "ws://localhost:4222" } * { broker_url: "wss://nats.example.com" }
* ); * );
*/ */
async function smartsend(subject, data, options = {}) { async function smartsend(subject, data, options = {}) {
@@ -711,9 +840,37 @@ async function smartreceive(msg, options = {}) {
const NATSBridgeCSR = { const NATSBridgeCSR = {
/** /**
* NATS client class for connection management * NATS client class for connection management
* Supports both single-use and persistent connection modes
*
* @example
* // Single-use connection (closes after publish)
* const client = new NATSBridgeCSR.NATSClient("wss://nats.example.com");
* await NATSBridgeCSR.smartsend("/test", [["msg", "Hello", "text"]], { nats_connection: client });
* await client.close();
*
* // Persistent connection (keeps connection open)
* const client = new NATSBridgeCSR.NATSClient("wss://nats.example.com", true);
* await client.connect();
* await NATSBridgeCSR.smartsend("/test1", [["msg", "Hello", "text"]], { nats_connection: client, is_publish: false });
* await NATSBridgeCSR.publishMessage(client, "/test2", JSON.stringify({msg: "World"}), "trace-id");
* // Connection remains open for more publishes
* await client.close();
*/ */
NATSClient, NATSClient,
/**
* Connection pool for managing multiple NATS connections
* Useful for applications with multiple concurrent publishers
*
* @example
* const pool = new NATSBridgeCSR.NATSConnectionPool("wss://nats.example.com", 10);
* const client = await pool.acquire();
* await NATSBridgeCSR.smartsend("/test", [["msg", "Hello", "text"]], { nats_connection: client });
* pool.release(client);
* await pool.closeAll();
*/
NATSConnectionPool,
/** /**
* Send data via NATS with automatic transport selection * Send data via NATS with automatic transport selection
*/ */
@@ -724,6 +881,19 @@ const NATSBridgeCSR = {
*/ */
smartreceive, smartreceive,
/**
* Publish message to NATS
*
* @example
* // Using a persistent connection
* const client = new NATSBridgeCSR.NATSClient("wss://nats.example.com", true);
* await client.connect();
* await NATSBridgeCSR.publishMessage(client, "/subject", JSON.stringify({msg: "Hello"}), "trace-id", false);
* // Connection stays open for more publishes
* await client.close();
*/
publishMessage,
/** /**
* Upload data to plik server in one-shot mode * Upload data to plik server in one-shot mode
*/ */

154
src/natsbridge_ssr.js
View File

@@ -1,6 +1,6 @@
/** /**
* NATSBridge - Cross-Platform Bi-Directional Data Bridge * NATSBridge - Cross-Platform Bi-Directional Data Bridge
* JavaScript/Node.js Implementation (Client-Side Rendering) * JavaScript/Node.js Implementation (Desktop/Server-Side)
* *
* This module provides functionality for sending and receiving data across network boundaries * This module provides functionality for sending and receiving data across network boundaries
* using NATS as the message bus, with support for both direct payload transport and * using NATS as the message bus, with support for both direct payload transport and
@@ -8,6 +8,12 @@
* *
* Supported payload types: "text", "dictionary", "arrowtable", "jsontable", "image", "audio", "video", "binary" * Supported payload types: "text", "dictionary", "arrowtable", "jsontable", "image", "audio", "video", "binary"
* *
* Node.js-specific features:
* - Apache Arrow IPC support via apache-arrow
* - TCP NATS connections (nats:// or tls:// URLs)
* - Buffer for binary data handling
* - Connection pooling for high-throughput scenarios
*
* @module NATSBridge * @module NATSBridge
*/ */
@@ -342,15 +348,18 @@ async function fetchWithBackoff(url, maxRetries, baseDelay, maxDelay, correlatio
/** /**
* NATS client wrapper for connection management * NATS client wrapper for connection management
* Supports both single-use and persistent connection modes
*/ */
class NATSClient { class NATSClient {
/** /**
* Create a new NATS client * Create a new NATS client
* @param {string} url - NATS server URL * @param {string} url - NATS server URL (nats:// or tls://)
* @param {boolean} [keepAlive=false] - Keep connection open for multiple publishes
*/ */
constructor(url) { constructor(url, keepAlive = false) {
this.url = url; this.url = url;
this.connection = null; this.connection = null;
this.keepAlive = keepAlive;
} }
/** /**
@@ -358,6 +367,9 @@ class NATSClient {
* @returns {Promise<NATS.Connection>} * @returns {Promise<NATS.Connection>}
*/ */
async connect() { async connect() {
if (this.connection) {
return this.connection;
}
this.connection = await nats.connect({ servers: this.url }); this.connection = await nats.connect({ servers: this.url });
return this.connection; return this.connection;
} }
@@ -382,8 +394,94 @@ class NATSClient {
async close() { async close() {
if (this.connection) { if (this.connection) {
this.connection.close(); this.connection.close();
this.connection = null;
} }
} }
/**
* Get the current connection (for external use)
* @returns {NATS.Connection|null}
*/
getConnection() {
return this.connection;
}
/**
* Check if connected
* @returns {boolean}
*/
isConnected() {
return this.connection !== null;
}
}
/**
* Connection pool for managing multiple NATS connections
* Useful for applications with multiple concurrent publishers
*/
class NATSConnectionPool {
/**
* Create a new connection pool
* @param {string} url - NATS server URL (nats:// or tls://)
* @param {number} [maxSize=10] - Maximum pool size
*/
constructor(url, maxSize = 10) {
this.url = url;
this.maxSize = maxSize;
this.connections = new Map();
this.idCounter = 0;
}
/**
* Get a connection from the pool (or create new)
* @returns {Promise<NATSClient>}
*/
async acquire() {
// Try to find an existing idle connection
for (const [id, client] of this.connections) {
if (client.isConnected()) {
return client;
}
}
// Create new connection if under limit
if (this.connections.size < this.maxSize) {
const id = `conn_${++this.idCounter}`;
const client = new NATSClient(this.url, true);
await client.connect();
this.connections.set(id, client);
return client;
}
// Pool exhausted - create new connection (caller should close when done)
const client = new NATSClient(this.url, false);
await client.connect();
return client;
}
/**
* Return a connection to the pool
* @param {NATSClient} client - Connection to return
*/
release(client) {
// Only return persistent connections
if (client.keepAlive && client.isConnected()) {
// Connection already in pool, do nothing
return;
}
// Non-persistent connection - close it
client.close();
}
/**
* Close all connections in the pool
*/
async closeAll() {
for (const [id, client] of this.connections) {
await client.close();
}
this.connections.clear();
}
} }
// ---------------------------------------------- Core Functions ---------------------------------------------- // // ---------------------------------------------- Core Functions ---------------------------------------------- //
@@ -394,9 +492,11 @@ class NATSClient {
* @param {string} subject - NATS subject to publish to * @param {string} subject - NATS subject to publish to
* @param {string} message - JSON message to publish * @param {string} message - JSON message to publish
* @param {string} correlationId - Correlation ID for tracing * @param {string} correlationId - Correlation ID for tracing
* @param {boolean} [closeConnection=true] - Close connection after publish (set false for persistent connections)
*/ */
async function publishMessage(brokerUrlOrClient, subject, message, correlationId) { async function publishMessage(brokerUrlOrClient, subject, message, correlationId, closeConnection = true) {
let conn; let conn;
let shouldClose = false;
if (brokerUrlOrClient instanceof NATSClient) { if (brokerUrlOrClient instanceof NATSClient) {
conn = brokerUrlOrClient; conn = brokerUrlOrClient;
@@ -410,15 +510,18 @@ async function publishMessage(brokerUrlOrClient, subject, message, correlationId
await brokerUrlOrClient.close(); await brokerUrlOrClient.close();
} }
}; };
shouldClose = true;
} else { } else {
// String URL - create new client // String URL - create new client
const client = new NATSClient(brokerUrlOrClient); const client = new NATSClient(brokerUrlOrClient);
conn = client; conn = client;
shouldClose = true;
} }
await conn.publish(subject, message, correlationId); await conn.publish(subject, message, correlationId);
if (conn instanceof NATSClient) { // Only close if explicitly requested and it's a short-lived client
if (shouldClose && closeConnection && conn instanceof NATSClient) {
await conn.close(); await conn.close();
} }
} }
@@ -764,9 +867,37 @@ async function smartreceive(msg, options = {}) {
const NATSBridge = { const NATSBridge = {
/** /**
* NATS client class for connection management * NATS client class for connection management
* Supports both single-use and persistent connection modes
*
* @example
* // Single-use connection (closes after publish)
* const client = new NATSBridge.NATSClient("nats://localhost:4222");
* await NATSBridge.smartsend("/test", [["msg", "Hello", "text"]], { nats_connection: client });
* await client.close();
*
* // Persistent connection (keeps connection open)
* const client = new NATSBridge.NATSClient("nats://localhost:4222", true);
* await client.connect();
* await NATSBridge.smartsend("/test1", [["msg", "Hello", "text"]], { nats_connection: client, is_publish: false });
* await NATSBridge.publishMessage(client, "/test2", JSON.stringify({msg: "World"}), "trace-id");
* // Connection remains open for more publishes
* await client.close();
*/ */
NATSClient, NATSClient,
/**
* Connection pool for managing multiple NATS connections
* Useful for applications with multiple concurrent publishers
*
* @example
* const pool = new NATSBridge.NATSConnectionPool("nats://localhost:4222", 10);
* const client = await pool.acquire();
* await NATSBridge.smartsend("/test", [["msg", "Hello", "text"]], { nats_connection: client });
* pool.release(client);
* await pool.closeAll();
*/
NATSConnectionPool,
/** /**
* Send data via NATS with automatic transport selection * Send data via NATS with automatic transport selection
*/ */
@@ -777,6 +908,19 @@ const NATSBridge = {
*/ */
smartreceive, smartreceive,
/**
* Publish message to NATS
*
* @example
* // Using a persistent connection
* const client = new NATSBridge.NATSClient("nats://localhost:4222", true);
* await client.connect();
* await NATSBridge.publishMessage(client, "/subject", JSON.stringify({msg: "Hello"}), "trace-id", false);
* // Connection stays open for more publishes
* await client.close();
*/
publishMessage,
/** /**
* Upload data to plik server in one-shot mode * Upload data to plik server in one-shot mode
*/ */