update readme

README.md

@@ -14,7 +14,6 @@ A high-performance, bi-directional data bridge for **Julia**, **JavaScript**, **
 - [Features](#features)
 - [Quick Start](#quick-start)
 - [API Reference](#api-reference)
-- [Payload Types](#payload-types)
 - [Cross-Platform Examples](#cross-platform-examples)
 - [Testing](#testing)
 - [Documentation](#documentation)
@@ -22,6 +21,73 @@ A high-performance, bi-directional data bridge for **Julia**, **JavaScript**, **
 
 ---
 
+## Quick Data Format Reference
+
+All platforms use the same input format for `smartpack()`:
+
+### Format: `[(dataname, data, type), ...]`
+
+| Element | Type | Description |
+|---------|------|-------------|
+| `dataname` | String | Name for the payload (e.g., `"message"`, `"config.json"`) |
+| `data` | Any | The actual data (type depends on the `type` parameter below) |
+| `type` | String | Payload type identifier |
+
+### Supported Payload Types
+
+| Type | Julia Data | JavaScript Data | Python Data | Description |
+|------|------------|-----------------|-------------|-------------|
+| `"text"` | `String` | `string` | `str` | Plain text |
+| `"dictionary"` | `Dict` | `Object` | `dict` | JSON object |
+| `"arrowtable"` | `DataFrame` | ❌ | `pandas.DataFrame` | Arrow IPC table (Desktop only) |
+| `"jsontable"` | `DataFrame` | `Array<Object>` | `list[dict]` | JSON table |
+| `"image"` | `Vector{UInt8}` | `Uint8Array` | `bytes` | Image data |
+| `"audio"` | `Vector{UInt8}` | `Uint8Array` | `bytes` | Audio data |
+| `"video"` | `Vector{UInt8}` | `Uint8Array` | `bytes` | Video data |
+| `"binary"` | `Vector{UInt8}` | `Uint8Array` | `bytes` | Binary data |
+
+### Examples
+
+**Sending multiple payloads:**
+```julia
+# Julia
+data = [
+    ("message", "Hello!", "text"),
+    ("config", Dict("key" => "value"), "dictionary"),
+    ("file", file_bytes, "binary")
+]
+env, json_str = msghandler.smartpack("subject", data, options...)
+```
+
+```python
+# Python
+data = [
+    ("message", "Hello!", "text"),
+    ("config", {"key": "value"}, "dictionary"),
+    ("file", file_bytes, "binary")
+]
+env, json_str = await smartpack("subject", data, **options)
+```
+
+```javascript
+// JavaScript
+const data = [
+    ["message", "Hello!", "text"],
+    ["config", {key: "value"}, "dictionary"],
+    ["file", fileBytes, "binary"]
+];
+const [env, json_str] = await smartpack("subject", data, options);
+```
+
+**Important Notes:**
+- Always wrap payloads in a list `[]`, even for single payloads
+- Type must be one of the supported types above
+- Large payloads (≥500KB) automatically use link transport
+- Browser only supports: `"text"`, `"dictionary"`, `"jsontable"`, `"image"`, `"audio"`, `"video"`, `"binary"`
+  (No Arrow IPC due to browser incompatibility)
+
+---
+
 ## Overview
 
 msghandler enables seamless communication across multiple platforms through NATS, with intelligent transport selection based on payload size:
@@ -109,6 +175,14 @@ msghandler enables seamless communication across multiple platforms through NATS
 ```julia
 using msghandler, NATS
 
+# Data format: [(dataname, data, type), ...]
+# Each tuple contains:
+#   1. dataname: String name for the payload (e.g., "message")
+#   2. data: The actual data (String, bytes, DataFrame, etc.)
+#   3. type: String type indicator (e.g., "text", "binary", "dictionary")
+#      Supported types: "text", "dictionary", "arrowtable", "jsontable", 
+#                       "image", "audio", "video", "binary"
+
 payload_1 = ("test_message", "Hello World", "text")
 
 file_path_large_image = "./test/large_image.png"
@@ -116,7 +190,7 @@ file_data_large_image = read(file_path_large_image)
 filename_large_image = basename(file_path_large_image)
 payload_2 = (filename_large_image, file_data_large_image, "binary")
 
-payloads = [payload_1, payload_2]  # payloads to be send format is [(dataname, data, type), ...] tuples.
+payloads = [payload_1, payload_2]  # List of tuples
 envelope, envelope_json_str = msghandler.smartpack("test.topic", 
                                                   payloads; 
                                                   broker_url="nats.yiem.cc",
@@ -159,6 +233,13 @@ console.log("Message sent!");
 ```python
 from msghandler import smartpack
 
+# Data format: [(dataname, data, type), ...]
+# Each tuple contains:
+#   1. dataname: String name for the payload (e.g., "message")
+#   2. data: The actual data (str, bytes, dict, list, etc.)
+#   3. type: String type indicator (e.g., "text", "binary", "dictionary")
+#      Supported types: "text", "dictionary", "jsontable", "image", "audio", "video", "binary"
+
 data = [("message", "Hello World", "text")]
 env, env_json_str = await smartpack(
     "/chat/room1",
@@ -211,14 +292,77 @@ end
 
 ### Unified API Standard
 
-All platforms use the same input/output format for payloads:
+All platforms use the same input/output format for payloads.
 
-**Input format for `smartpack`:**
+#### Input Format for `smartpack`
-```
+
-[(dataname1, data1, type1), (dataname2, data2, type2), ...]
+**Format:** `[(dataname1, data1, type1), (dataname2, data2, type2), ...]`
+
+**Each tuple contains 3 elements:**
+1. **`dataname`** (String) - Name for the payload (e.g., `"message"`, `"config.json"`, `"avatar.png"`)
+2. **`data`** (Any) - The actual data to send (type depends on `type`):
+   - `text` → String
+   - `dictionary` → Dict/Object
+   - `arrowtable` → DataFrame/Arrow.Table
+   - `jsontable` → List of dicts/Vector{Dict}
+   - `image/audio/video/binary` → bytes/Uint8Array/Vector{UInt8}
+3. **`type`** (String) - Payload type (required):
+   - `"text"` - Plain text string
+   - `"dictionary"` - JSON-serializable dictionary
+   - `"arrowtable"` - Apache Arrow IPC table (Desktop only)
+   - `"jsontable"` - JSON table (all platforms)
+   - `"image"` - Image data (PNG, JPG)
+   - `"audio"` - Audio data (WAV, MP3)
+   - `"video"` - Video data (MP4, AVI)
+   - `"binary"` - Generic binary data
+
+**Important:**
+- Always wrap payloads in a list, even for single payloads
+- Type must be one of the supported types above
+- Large payloads (≥500KB by default) automatically use link transport
+
+**Example:**
+```julia
+# Julia
+data = [
+    ("message", "Hello World", "text"),
+    ("config", Dict("key" => "value"), "dictionary"),
+    ("file", file_bytes, "binary")
+]
 ```
 
-**Output format for `smartunpack`:**
+```python
+# Python
+data = [
+    ("message", "Hello World", "text"),
+    ("config", {"key": "value"}, "dictionary"),
+    ("file", file_bytes, "binary")
+]
+```
+
+```javascript
+// JavaScript
+const data = [
+    ["message", "Hello World", "text"],
+    ["config", {key: "value"}, "dictionary"],
+    ["file", fileBytes, "binary"]
+];
+```
+
+### Common Payload Examples
+
+| Use Case | Data Format | Type |
+|----------|-------------|------|
+| Simple text message | `("message", "Hello World", "text")` | `"text"` |
+| Configuration JSON | `("config", Dict("key" => "value"), "dictionary")` | `"dictionary"` |
+| Table as Arrow | `("data", dataframe, "arrowtable")` | `"arrowtable"` |
+| Table as JSON | `("data", [{"col": 1}], "jsontable")` | `"jsontable"` |
+| Image file | `("avatar.png", read("file.png"), "image")` | `"image"` |
+| Audio file | `("audio.mp3", audio_bytes, "audio")` | `"audio"` |
+| Video file | `("video.mp4", video_bytes, "video")` | `"video"` |
+| Binary file | `("data.bin", file_bytes, "binary")` | `"binary"` |
+
+#### Output Format for `smartunpack`
 ```json
 {
   "correlation_id": "...",
@@ -454,21 +598,6 @@ print("Received payloads:", env["payloads"])
 
 ---
 
-## Payload Types
-
-| Type | Julia | JavaScript | Python | MicroPython | Description |
-|------|-------|------------|--------|-------------|-------------|
-| `text` | `String` | `string` | `str` | `str` | Plain text strings |
-| `dictionary` | `Dict`, `NamedTuple` | `Object`, `Array` | `dict`, `list` | `dict` | JSON-serializable dictionaries |
-| `arrowtable` | `DataFrame`, `Arrow.Table` | ❌ (Browser), ✅ (Node.js) | `pandas.DataFrame` | ❌ | Tabular data (Arrow IPC) |
-| `jsontable` | `DataFrame`, `Vector{NamedTuple}` | `Array<Object>` | `list[dict]` | ⚠️ | Tabular data (JSON) - **Only table type in Browser** |
-| `image` | `Vector{UInt8}` | `Uint8Array`, `Buffer` | `bytes` | `bytearray` | Image data (PNG, JPG) |
-| `audio` | `Vector{UInt8}` | `Uint8Array`, `Buffer` | `bytes` | `bytearray` | Audio data (WAV, MP3) |
-| `video` | `Vector{UInt8}` | `Uint8Array`, `Buffer` | `bytes` | `bytearray` | Video data (MP4, AVI) |
-| `binary` | `Vector{UInt8}`, `IOBuffer` | `Uint8Array`, `Buffer` | `bytes`, `bytearray` | `bytearray` | Generic binary data |
-
----
-
 ## Cross-Platform Examples
 
 ### Example 1: Chat with Mixed Content