944 lines
23 KiB
Markdown
944 lines
23 KiB
Markdown
# msghandler - Cross-Platform Bi-Directional Data Bridge
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A high-performance, bi-directional data bridge for **Julia**, **JavaScript**, **Python**, and **MicroPython** applications using NATS (Core & JetStream), implementing the Claim-Check pattern for large payloads.
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[](https://opensource.org/licenses/MIT)
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[](https://nats.io)
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---
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## Table of Contents
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- [Overview](#overview)
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- [Cross-Platform Support](#cross-platform-support)
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- [Features](#features)
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- [Quick Start](#quick-start)
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- [API Reference](#api-reference)
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- [Payload Types](#payload-types)
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- [Cross-Platform Examples](#cross-platform-examples)
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- [Testing](#testing)
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- [Documentation](#documentation)
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- [License](#license)
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---
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## Overview
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msghandler enables seamless communication across multiple platforms through NATS, with intelligent transport selection based on payload size:
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| Transport | Payload Size | Method |
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|-----------|--------------|--------|
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| **Direct** | < 500KB | Sent directly via NATS (Base64 encoded) |
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| **Link** | ≥ 500KB | Uploaded to HTTP file server, URL sent via NATS |
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### Use Cases
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- **Chat Applications**: Text, images, audio, video in a single message
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- **File Transfer**: Efficient transfer of large files using claim-check pattern
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- **IoT/Embedded**: Sensor data, telemetry, and analytics pipelines (MicroPython)
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- **Cross-Platform Communication**: Interoperability between Julia, JavaScript, Python, and MicroPython systems
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---
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## Cross-Platform Support
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| Platform | Implementation | Features |
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|----------|----------------|----------|
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| **Julia** | [`src/msghandler.jl`](src/msghandler.jl) | Full feature set, Arrow IPC, multiple dispatch |
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| **JavaScript (Node.js)** | [`src/msghandler_ssr.js`](src/msghandler_ssr.js) | Node.js, async/await, Arrow IPC |
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| **JavaScript (Browser)** | [`src/msghandler_csr.js`](src/msghandler_csr.js) | Browser, WebSocket NATS, async/await, JSON table only |
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| **Python** | [`src/msghandler.py`](src/msghandler.py) | Desktop Python, asyncio, type hints, Arrow IPC |
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| **MicroPython** | [`src/msghandler_mpy.py`](src/msghandler_mpy.py) | Memory-constrained, synchronous API |
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### Platform Comparison
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| Feature | Julia | JavaScript | JavaScript (Browser) | Python | MicroPython |
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|---------|-------|------------|----------------------|--------|-------------|
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| Multiple Dispatch | ✅ Native | ❌ | ❌ | ❌ | ❌ |
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| Async/Await | ❌ | ✅ Native | ✅ Native | ✅ Native | ⚠️ (uasyncio) |
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| Type Safety | ✅ Strong | ⚠️ (TypeScript) | ⚠️ (TypeScript) | ✅ (Type hints) | ❌ |
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| Arrow IPC | ✅ Native | ✅ Native | ❌ (Browser incompatible) | ✅ Native | ❌ |
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| JSON Table | ✅ | ✅ | ✅ (Only table type) | ✅ | ⚠️ (Limited) |
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| Direct Transport | ✅ | ✅ | ✅ | ✅ | ✅ |
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| Link Transport | ✅ | ✅ | ✅ | ✅ | ⚠️ (Limited) |
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| Handler Functions | ✅ | ✅ | ✅ | ✅ | ✅ |
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| Cross-Platform API | ✅ | ✅ | ✅ | ✅ | ✅ |
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| WebSocket NATS | ❌ | ❌ | ✅ | ❌ | ❌ |
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---
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## Features
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- ✅ **Cross-platform messaging** for Julia, JavaScript, Python, and MicroPython applications
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- ✅ **Bi-directional messaging** with request-reply patterns
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- ✅ **Multi-payload support** - send multiple payloads with different types in one message
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- ✅ **Automatic transport selection** - direct vs link based on payload size
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- ✅ **Claim-Check pattern** for payloads ≥ 500KB
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- ✅ **Apache Arrow IPC** support for tabular data (Desktop: Julia/Python/Node.js)
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- ✅ **JSON Table** support for tabular data (All platforms including Browser)
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- ✅ **Exponential backoff** for reliable file server downloads
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- ✅ **Correlation ID tracking** for message tracing
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- ✅ **Reply-to support** for request-response patterns
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- ✅ **Handler function abstraction** - pluggable file server implementations (Plik, AWS S3, custom)
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---
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## Quick Start
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### Prerequisites
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1. **NATS Server** - Install and run a NATS server:
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```bash
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docker run -p 4222:4222 nats:latest
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```
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2. **HTTP File Server** (optional, for large payloads) - Install and run a file server:
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```bash
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# Using Plik
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docker run -p 8080:8080 -v /tmp/fileserver:/var/lib/plik -e PLIK_ADMIN_PASSWORD=admin plik/plik
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# OR using simple Python HTTP server
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mkdir -p /tmp/fileserver
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python3 -m http.server 8080 --directory /tmp/fileserver
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```
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### Send Your First Message
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#### Julia
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```julia
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using msghandler
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data = [("message", "Hello World", "text")]
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env, env_json_str = smartpack("/chat/room1", data; broker_url="nats://localhost:4222")
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println("Message sent!")
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```
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#### JavaScript (Node.js)
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```javascript
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import msghandler from './src/msghandler_ssr.js';
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const data = [["message", "Hello World", "text"]];
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const [env, env_json_str] = await msghandler.smartpack(
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"/chat/room1",
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data,
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{ broker_url: "nats://localhost:4222" }
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);
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console.log("Message sent!");
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```
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#### JavaScript (Browser)
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```javascript
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import msghandler from './src/msghandler_csr.js';
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const data = [["message", "Hello World", "text"]];
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const [env, env_json_str] = await msghandler.smartpack(
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"/chat/room1",
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data,
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{ broker_url: "ws://localhost:4222" }
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);
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console.log("Message sent!");
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```
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#### Python
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```python
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from msghandler import smartpack
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data = [("message", "Hello World", "text")]
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env, env_json_str = await smartpack(
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"/chat/room1",
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data,
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broker_url="nats://localhost:4222"
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)
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print("Message sent!")
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```
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#### MicroPython
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```python
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from msghandler import smartpack
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data = [("message", "Hello World", "text")]
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env, env_json_str = smartpack(
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"/chat/room1",
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data,
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broker_url="nats://localhost:4222",
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size_threshold=100000 # 100KB for MicroPython
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)
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print("Message sent!")
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```
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---
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## API Reference
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### Unified API Standard
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All platforms use the same input/output format for payloads:
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**Input format for `smartpack`:**
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```
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[(dataname1, data1, type1), (dataname2, data2, type2), ...]
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```
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**Output format for `smartunpack`:**
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```json
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{
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"correlation_id": "...",
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"msg_id": "...",
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"timestamp": "...",
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"send_to": "...",
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"msg_purpose": "...",
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"sender_name": "...",
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"sender_id": "...",
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"receiver_name": "...",
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"receiver_id": "...",
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"reply_to": "...",
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"reply_to_msg_id": "...",
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"broker_url": "...",
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"metadata": {...},
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"payloads": [(dataname1, data1, type1), (dataname2, data2, type2), ...]
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}
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```
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### smartpack
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Sends data either directly via NATS or via a fileserver URL, depending on payload size.
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#### Julia
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```julia
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using msghandler
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env, env_json_str = msghandler.smartpack(
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subject::String,
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data::AbstractArray{Tuple{String, Any, String}};
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broker_url::String = "nats://localhost:4222",
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fileserver_url = "http://localhost:8080",
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fileserver_upload_handler::Function = plik_oneshot_upload,
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size_threshold::Int = 500_000,
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correlation_id::String = string(uuid4()),
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msg_purpose::String = "chat",
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sender_name::String = "msghandler",
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receiver_name::String = "",
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receiver_id::String = "",
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reply_to::String = "",
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reply_to_msg_id::String = "",
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is_publish::Bool = true,
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NATS_connection::Union{NATS.Connection, Nothing} = nothing,
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msg_id::String = string(uuid4()),
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sender_id::String = string(uuid4())
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)
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# Returns: ::Tuple{msg_envelope_v1, String}
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```
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#### JavaScript (Node.js)
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```javascript
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import msghandler from './src/msghandler_ssr.js';
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const [env, env_json_str] = await msghandler.smartpack(
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subject,
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data, // Array of [dataname, data, type] tuples
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{
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broker_url: 'nats://localhost:4222',
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fileserver_url: 'http://localhost:8080',
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fileserver_upload_handler: msghandler.plikOneshotUpload,
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size_threshold: 500_000,
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correlation_id: uuidv4(),
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msg_purpose: 'chat',
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sender_name: 'msghandler',
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receiver_name: '',
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receiver_id: '',
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reply_to: '',
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reply_to_msg_id: '',
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is_publish: true,
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nats_connection: null,
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msg_id: uuidv4(),
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sender_id: uuidv4()
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}
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);
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// Returns: Promise<[env, env_json_str]>
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```
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#### JavaScript (Browser)
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```javascript
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import msghandler from './src/msghandler_csr.js';
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const [env, env_json_str] = await msghandler.smartpack(
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subject,
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data,
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{
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broker_url: 'ws://localhost:4222',
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fileserver_url: 'http://localhost:8080',
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fileserver_upload_handler: msghandler.plikOneshotUpload,
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size_threshold: 500_000,
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correlation_id: uuidv4(),
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msg_purpose: 'chat',
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sender_name: 'msghandler',
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receiver_name: '',
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receiver_id: '',
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reply_to: '',
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reply_to_msg_id: '',
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is_publish: true,
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nats_connection: null,
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msg_id: uuidv4(),
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sender_id: uuidv4()
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}
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);
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// Returns: Promise<[env, env_json_str]>
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```
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#### Python
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```python
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from msghandler import msghandler
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env, env_json_str = await msghandler.smartpack(
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subject: str,
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data: List[Tuple[str, Any, str]],
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broker_url: str = "nats://localhost:4222",
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fileserver_url: str = "http://localhost:8080",
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fileserver_upload_handler: Callable = plik_oneshot_upload,
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size_threshold: int = 500_000,
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correlation_id: str = None,
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msg_purpose: str = "chat",
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sender_name: str = "msghandler",
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receiver_name: str = "",
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receiver_id: str = "",
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reply_to: str = "",
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reply_to_msg_id: str = "",
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is_publish: bool = True,
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nats_connection: Any = None,
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msg_id: str = None,
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sender_id: str = None
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)
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# Returns: Tuple[Dict, str]
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```
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#### MicroPython
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```python
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from msghandler import msghandler
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# Limited to direct transport (< 100KB threshold)
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env, env_json_str = msghandler.smartpack(
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subject,
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data, # List of (dataname, data, type) tuples
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broker_url="nats://localhost:4222",
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size_threshold=100000 # Lower threshold for memory constraints
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)
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# Returns: Tuple[Dict, str]
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```
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### smartunpack
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Receives and processes messages from NATS, handling both direct and link transport.
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#### Julia
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```julia
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using msghandler
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env = msghandler.smartunpack(
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msg::NATS.Msg;
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fileserver_download_handler::Function = _fetch_with_backoff,
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max_retries::Int = 5,
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base_delay::Int = 100,
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max_delay::Int = 5000
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)
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# Returns: ::JSON.Object{String, Any}
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```
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#### JavaScript (Node.js)
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```javascript
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import msghandler from './src/msghandler_ssr.js';
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const env = await msghandler.smartunpack(
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msg,
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{
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fileserver_download_handler: msghandler.fetchWithBackoff,
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max_retries: 5,
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base_delay: 100,
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max_delay: 5000
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}
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);
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// Returns: Promise<env_object>
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```
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#### JavaScript (Browser)
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```javascript
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import msghandler from './src/msghandler_csr.js';
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const env = await msghandler.smartunpack(
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msg,
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{
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fileserver_download_handler: msghandler.fetchWithBackoff,
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max_retries: 5,
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base_delay: 100,
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max_delay: 5000
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}
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);
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// Returns: Promise<env_object>
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```
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#### Python
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```python
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from msghandler import msghandler
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env = await msghandler.smartunpack(
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msg,
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fileserver_download_handler=fetch_with_backoff,
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max_retries=5,
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base_delay=100,
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max_delay=5000
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)
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# Returns: Dict with "payloads" key
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```
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#### MicroPython
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```python
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from msghandler import msghandler
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env = msghandler.smartunpack(
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msg,
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fileserver_download_handler=_sync_fileserver_download,
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max_retries=3,
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base_delay=100,
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max_delay=1000
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)
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# Returns: Dict with "payloads" key
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```
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---
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## Payload Types
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| Type | Julia | JavaScript | Python | MicroPython | Description |
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|------|-------|------------|--------|-------------|-------------|
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| `text` | `String` | `string` | `str` | `str` | Plain text strings |
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| `dictionary` | `Dict`, `NamedTuple` | `Object`, `Array` | `dict`, `list` | `dict` | JSON-serializable dictionaries |
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| `arrowtable` | `DataFrame`, `Arrow.Table` | ❌ (Browser), ✅ (Node.js) | `pandas.DataFrame` | ❌ | Tabular data (Arrow IPC) |
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| `jsontable` | `DataFrame`, `Vector{NamedTuple}` | `Array<Object>` | `list[dict]` | ⚠️ | Tabular data (JSON) - **Only table type in Browser** |
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| `image` | `Vector{UInt8}` | `Uint8Array`, `Buffer` | `bytes` | `bytearray` | Image data (PNG, JPG) |
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| `audio` | `Vector{UInt8}` | `Uint8Array`, `Buffer` | `bytes` | `bytearray` | Audio data (WAV, MP3) |
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| `video` | `Vector{UInt8}` | `Uint8Array`, `Buffer` | `bytes` | `bytearray` | Video data (MP4, AVI) |
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| `binary` | `Vector{UInt8}`, `IOBuffer` | `Uint8Array`, `Buffer` | `bytes`, `bytearray` | `bytearray` | Generic binary data |
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---
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## Cross-Platform Examples
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### Example 1: Chat with Mixed Content
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Send text, image, and large file in one message.
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#### Julia
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```julia
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using msghandler
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data = [
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("message_text", "Hello!", "text"),
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("user_avatar", image_data, "image"),
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("large_document", large_file_data, "binary")
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]
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env, env_json_str = smartpack("/chat/room1", data; fileserver_url="http://localhost:8080")
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```
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#### JavaScript (Node.js)
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```javascript
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import msghandler from './src/msghandler_ssr.js';
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const data = [
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["message_text", "Hello!", "text"],
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["user_avatar", imageData, "image"],
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["large_document", largeFileData, "binary"]
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];
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const [env, env_json_str] = await msghandler.smartpack(
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"/chat/room1",
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data,
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{ fileserver_url: 'http://localhost:8080' }
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);
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```
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#### JavaScript (Browser)
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```javascript
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import msghandler from './src/msghandler_csr.js';
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const data = [
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["message_text", "Hello!", "text"],
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["user_avatar", imageData, "image"],
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["large_document", largeFileData, "binary"]
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];
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const [env, env_json_str] = await msghandler.smartpack(
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"/chat/room1",
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data,
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{ broker_url: 'ws://localhost:4222', fileserver_url: 'http://localhost:8080' }
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);
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```
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#### Python
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```python
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from msghandler import msghandler
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data = [
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("message_text", "Hello!", "text"),
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("user_avatar", image_data, "image"),
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("large_document", large_file_data, "binary")
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]
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env, env_json_str = await msghandler.smartpack(
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"/chat/room1",
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data,
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fileserver_url="http://localhost:8080"
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)
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```
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### Example 2: Dictionary Exchange
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Send configuration data between platforms.
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#### Julia
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```julia
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using msghandler
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config = Dict(
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"wifi_ssid" => "MyNetwork",
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"wifi_password" => "password123",
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"update_interval" => 60
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)
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data = [("config", config, "dictionary")]
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env, env_json_str = smartpack("/device/config", data)
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```
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#### JavaScript (Node.js)
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```javascript
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import msghandler from './src/msghandler_ssr.js';
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const config = {
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wifi_ssid: "MyNetwork",
|
|
wifi_password: "password123",
|
|
update_interval: 60
|
|
};
|
|
|
|
const [env, env_json_str] = await msghandler.smartpack(
|
|
"/device/config",
|
|
[["config", config, "dictionary"]]
|
|
);
|
|
```
|
|
|
|
#### Python
|
|
|
|
```python
|
|
from msghandler import msghandler
|
|
|
|
config = {
|
|
"wifi_ssid": "MyNetwork",
|
|
"wifi_password": "password123",
|
|
"update_interval": 60
|
|
}
|
|
|
|
data = [("config", config, "dictionary")]
|
|
env, env_json_str = await msghandler.smartpack("/device/config", data)
|
|
```
|
|
|
|
### Example 3: Table Data (Arrow IPC)
|
|
|
|
Send tabular data using Apache Arrow IPC format.
|
|
|
|
#### Julia
|
|
|
|
```julia
|
|
using msghandler
|
|
using DataFrames
|
|
|
|
df = DataFrame(
|
|
id = [1, 2, 3],
|
|
name = ["Alice", "Bob", "Charlie"],
|
|
score = [95, 88, 92]
|
|
)
|
|
|
|
data = [("students", df, "arrowtable")]
|
|
env, env_json_str = smartpack("/data/analysis", data)
|
|
```
|
|
|
|
#### JavaScript (Node.js)
|
|
|
|
```javascript
|
|
import msghandler from './src/msghandler_ssr.js';
|
|
|
|
const df = [
|
|
{ id: 1, name: "Alice", score: 95 },
|
|
{ id: 2, name: "Bob", score: 88 },
|
|
{ id: 3, name: "Charlie", score: 92 }
|
|
];
|
|
|
|
const [env, env_json_str] = await msghandler.smartpack(
|
|
"/data/analysis",
|
|
[["students", df, "arrowtable"]]
|
|
);
|
|
```
|
|
|
|
#### Python
|
|
|
|
```python
|
|
from msghandler import msghandler
|
|
import pandas as pd
|
|
|
|
df = pd.DataFrame({
|
|
"id": [1, 2, 3],
|
|
"name": ["Alice", "Bob", "Charlie"],
|
|
"score": [95, 88, 92]
|
|
})
|
|
|
|
data = [("students", df, "arrowtable")]
|
|
env, env_json_str = await msghandler.smartpack("/data/analysis", data)
|
|
```
|
|
|
|
#### JavaScript (Browser)
|
|
|
|
```javascript
|
|
import msghandler from './src/msghandler_csr.js';
|
|
|
|
// Browser uses jsontable (JSON array of objects) instead of arrowtable
|
|
// Apache Arrow is not compatible with browsers
|
|
const df = [
|
|
{ id: 1, name: "Alice", score: 95 },
|
|
{ id: 2, name: "Bob", score: 88 },
|
|
{ id: 3, name: "Charlie", score: 92 }
|
|
];
|
|
|
|
const [env, env_json_str] = await msghandler.smartpack(
|
|
"/data/analysis",
|
|
[["students", df, "jsontable"]], // Use jsontable for browser
|
|
{ broker_url: 'ws://localhost:4222' }
|
|
);
|
|
```
|
|
|
|
### Example 4: Request-Response Pattern
|
|
|
|
Bi-directional communication with reply-to support.
|
|
|
|
#### Julia
|
|
|
|
```julia
|
|
using msghandler
|
|
|
|
# Requester
|
|
env, env_json_str = smartpack(
|
|
"/device/command",
|
|
[("command", Dict("action" => "read_sensor"), "dictionary")];
|
|
broker_url="nats://localhost:4222",
|
|
reply_to="/device/response"
|
|
)
|
|
|
|
# Receiver (in separate application)
|
|
msg = NATS.subscription.next()
|
|
env = smartunpack(msg)
|
|
# Process request and send response
|
|
response_env, response_json = smartpack(
|
|
"/device/response",
|
|
[("result", Dict("value" => 42), "dictionary")],
|
|
reply_to="/device/command",
|
|
reply_to_msg_id=env["msg_id"]
|
|
)
|
|
```
|
|
|
|
#### JavaScript (Node.js)
|
|
|
|
```javascript
|
|
import msghandler from './src/msghandler_ssr.js';
|
|
|
|
// Requester
|
|
const [env, env_json_str] = await msghandler.smartpack(
|
|
"/device/command",
|
|
[["command", { action: "read_sensor" }, "dictionary"]],
|
|
{ broker_url: 'nats://localhost:4222', reply_to: '/device/response' }
|
|
);
|
|
|
|
// Receiver (in separate application)
|
|
// const msg = await natsConsumer.next();
|
|
// const env = await msghandler.smartunpack(msg);
|
|
// Process request and send response
|
|
// const response_env, response_json = await msghandler.smartpack(
|
|
// "/device/response",
|
|
// [["result", { value: 42 }, "dictionary"]],
|
|
// { reply_to: '/device/command', reply_to_msg_id: env.msg_id }
|
|
// );
|
|
```
|
|
|
|
#### Python
|
|
|
|
```python
|
|
from msghandler import msghandler
|
|
|
|
# Requester
|
|
env, env_json_str = await msghandler.smartpack(
|
|
"/device/command",
|
|
[("command", {"action": "read_sensor"}, "dictionary")],
|
|
broker_url="nats://localhost:4222",
|
|
reply_to="/device/response"
|
|
)
|
|
|
|
# Receiver (in separate application)
|
|
# msg = await nats_consumer.next()
|
|
# env = await msghandler.smartunpack(msg)
|
|
# Process request and send response
|
|
# response_env, response_json = await msghandler.smartpack(
|
|
# "/device/response",
|
|
# [("result", {"value": 42}, "dictionary")],
|
|
# reply_to="/device/command",
|
|
# reply_to_msg_id=env["msg_id"]
|
|
# )
|
|
```
|
|
|
|
---
|
|
|
|
## Testing
|
|
|
|
### Test File Organization
|
|
|
|
| Platform | Sender Tests | Receiver Tests |
|
|
|----------|--------------|----------------|
|
|
| **Julia** | `test/test_julia_*_sender.jl` | `test/test_julia_*_receiver.jl` |
|
|
| **JavaScript** | `test/test_js_*_sender.js` | `test/test_js_*_receiver.js` |
|
|
| **Python** | `test/test_py_*_sender.py` | `test/test_py_*_receiver.py` |
|
|
|
|
### Run Tests
|
|
|
|
#### Julia
|
|
|
|
```bash
|
|
# Text message exchange
|
|
julia test/test_julia_text_sender.jl
|
|
julia test/test_julia_text_receiver.jl
|
|
|
|
# Dictionary exchange
|
|
julia test/test_julia_dict_sender.jl
|
|
julia test/test_julia_dict_receiver.jl
|
|
|
|
# File transfer
|
|
julia test/test_julia_file_sender.jl
|
|
julia test/test_julia_file_receiver.jl
|
|
|
|
# Mixed payload types
|
|
julia test/test_julia_mix_payloads_sender.jl
|
|
julia test/test_julia_mix_payloads_receiver.jl
|
|
|
|
# Table exchange
|
|
julia test/test_julia_table_sender.jl
|
|
julia test/test_julia_table_receiver.jl
|
|
```
|
|
|
|
#### JavaScript (Node.js)
|
|
|
|
```bash
|
|
# Text message exchange
|
|
node test/test_js_text_sender.js
|
|
node test/test_js_text_receiver.js
|
|
|
|
# Dictionary exchange
|
|
node test/test_js_dictionary_sender.js
|
|
node test/test_js_dictionary_receiver.js
|
|
|
|
# Binary transfer
|
|
node test/test_js_binary_sender.js
|
|
node test/test_js_binary_receiver.js
|
|
|
|
# Table exchange
|
|
node test/test_js_table_sender.js
|
|
node test/test_js_table_receiver.js
|
|
```
|
|
|
|
#### Python
|
|
|
|
```bash
|
|
# Text message exchange
|
|
python3 test/test_py_text_sender.py
|
|
python3 test/test_py_text_receiver.py
|
|
|
|
# Dictionary exchange
|
|
python3 test/test_py_dictionary_sender.py
|
|
python3 test/test_py_dictionary_receiver.py
|
|
|
|
# Binary transfer
|
|
python3 test/test_py_binary_sender.py
|
|
python3 test/test_py_binary_receiver.py
|
|
|
|
# Table exchange
|
|
python3 test/test_py_table_sender.py
|
|
python3 test/test_py_table_receiver.py
|
|
```
|
|
|
|
---
|
|
|
|
## Browser Deployment
|
|
|
|
### Using with Node.js Build Tools
|
|
|
|
The browser implementation (`src/msghandler_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/msghandler_csr.js'],
|
|
bundle: true,
|
|
outfile: 'dist/msghandler-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/msghandler-csr-bundle.js"></script>
|
|
<script type="module">
|
|
import msghandlerCSR from './dist/msghandler-csr-bundle.js';
|
|
|
|
// Use the library
|
|
const [env, envJson] = await msghandlerCSR.smartpack(
|
|
"/chat/user/v1/message",
|
|
[["msg", "Hello", "text"]],
|
|
{ broker_url: "wss://nats.example.com" }
|
|
);
|
|
</script>
|
|
</body>
|
|
</html>
|
|
```
|
|
|
|
---
|
|
|
|
## Documentation
|
|
|
|
For detailed architecture and implementation information, see:
|
|
|
|
- [`docs/architecture.md`](docs/architecture.md) - Cross-platform architecture, API parity, platform-specific patterns
|
|
- [`docs/requirements.md`](docs/requirements.md) - Business requirements and user stories
|
|
- [`docs/spec.md`](docs/spec.md) - Technical specification and contracts
|
|
- [`docs/walkthrough.md`](docs/walkthrough.md) - Real-world application building guides
|
|
|
|
---
|
|
|
|
## License
|
|
|
|
MIT License
|
|
|
|
Copyright (c) 2026 msghandler Contributors
|
|
|
|
Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
of this software and associated documentation files (the "Software"), to deal
|
|
in the Software without restriction, including without limitation the rights
|
|
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
copies of the Software, and to permit persons to whom the Software is
|
|
furnished to do so, subject to the following conditions:
|
|
|
|
The above copyright notice and this permission notice shall be included in all
|
|
copies or substantial portions of the Software.
|
|
|
|
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
SOFTWARE.
|