Tauri Plugin — SerialPort

A comprehensive plugin for Tauri applications to communicate with serial ports. This plugin provides a complete API for reading from and writing to serial devices, with support for various configuration options and control signals.

Installation
Basic Usage
TypeScript Support
Rust Usage
Permissions
API Reference
6.1. Port Discovery
6.2. Connection Management
6.3. Data Transfer
6.4. Port Configuration
6.5. Control Signals
6.6. Buffer Management
Common Use Cases
Android Setup
Contributing
Development Setup
Testing
Partners
License

Installation

Prerequisites

Rust version 1.70 or higher
Tauri 2.0 or higher
Node.js and an npm-compatible package manager (npm, yarn, pnpm)

Installation Methods

Using crates.io and npm (Recommended)

# Install the Rust dependency
cargo add tauri-plugin-serialplugin

# Install JavaScript bindings
npm add tauri-plugin-serialplugin
# or
yarn add tauri-plugin-serialplugin
# or
pnpm add tauri-plugin-serialplugin

Basic Usage

Register the Plugin

// src-tauri/src/main.rs
fn main() {
    tauri::Builder::default()
        .plugin(tauri_plugin_serialplugin::init())
        .run(tauri::generate_context!())
        .expect("error while running tauri application");
}

Configure Permissions

// src-tauri/capabilities/default.json
{
  "$schema": "../gen/schemas/desktop-schema.json",
  "identifier": "default",
  "description": "Capability for the main window",
  "windows": ["main"],
  "permissions": [
    "core:default",
    "serialplugin:default"
  ]
}

Basic Example

import { SerialPort } from "tauri-plugin-serialplugin";

// List available ports
const ports = await SerialPort.available_ports();
console.log("Available ports:", ports);

// Open a port
const port = new SerialPort({
  path: "COM1",
  baudRate: 9600
});
await port.open();

// Write data
await port.write("Hello, Serial Port!");

// Start port listening
const unsubscribe = await port.listen((data) => {
  console.log("Received:", data);
});

// Stop listening when done
await port.cancelListen();

// Close port
await port.close();

Error Handling Example

import { SerialPort } from "tauri-plugin-serialplugin";

async function handleSerialPort() {
  let port: SerialPort | null = null;

  try {
    // List available ports
    const ports = await SerialPort.available_ports();
    if (Object.keys(ports).length === 0) {
      throw new Error("No serial ports found");
    }

    // Open port
    port = new SerialPort({
      path: "COM1",
      baudRate: 9600
    });

    try {
      await port.open();
    } catch (error) {
      throw new Error(`Failed to open port: ${error}`);
    }

    try {
      // Write data
      await port.write("Test data");
    } catch (error) {
      throw new Error(`Failed to write data: ${error}`);
    }

    try {
      // Read data
      const data = await port.read({ timeout: 1000 });
      console.log("Received:", data);
    } catch (error) {
      throw new Error(`Failed to read data: ${error}`);
    }

    try {
      // Start listening
      await port.startListening();
      await port.listen((data) => {
        console.log("Received:", data);
      });
    } catch (error) {
      throw new Error(`Failed to start listening: ${error}`);
    }

    try {
      // Configure port settings
      await port.setBaudRate(115200);
      await port.setDataBits(DataBits.Eight);
      await port.setFlowControl(FlowControl.None);
      await port.setParity(Parity.None);
      await port.setStopBits(StopBits.One);
      await port.setTimeout(1000);
    } catch (error) {
      throw new Error(`Failed to configure port: ${error}`);
    }

  } catch (error) {
    // Handle all errors in one place
    console.error("Serial port error:", error);
  } finally {
    // Clean up
    if (port) {
      try {
        await port.cancelListen();
        await port.close();
      } catch (error) {
        console.error("Error during cleanup:", error);
      }
    }
  }
}

// Usage
handleSerialPort();

TypeScript Support

This plugin provides full TypeScript support with comprehensive type definitions. All methods, interfaces, and enums are properly typed for better development experience.

Available Types

import { 
  SerialPort, 
  DataBits, 
  FlowControl, 
  Parity, 
  StopBits, 
  ClearBuffer,
  PortInfo,
  SerialportOptions,
  ReadOptions 
} from "tauri-plugin-serialplugin";

Type Definitions

SerialPort - Main class for serial port operations
DataBits - Enum: Five, Six, Seven, Eight
FlowControl - Enum: None, Software, Hardware
Parity - Enum: None, Odd, Even
StopBits - Enum: One, Two
ClearBuffer - Enum: Input, Output, All
PortInfo - Interface for port information
SerialportOptions - Interface for port configuration
ReadOptions - Interface for read operation options

Configuration Example with Types

import { SerialPort, DataBits, FlowControl, Parity, StopBits } from "tauri-plugin-serialplugin";

const port = new SerialPort({
  path: "/dev/ttyUSB0",
  baudRate: 9600,
  dataBits: DataBits.Eight,        // Type-safe enum
  flowControl: FlowControl.None,   // Type-safe enum
  parity: Parity.None,             // Type-safe enum
  stopBits: StopBits.One,          // Type-safe enum
  timeout: 1000,
  size: 1024
});

// All configuration methods are fully typed
await port.setBaudRate(115200);
await port.setDataBits(DataBits.Eight);
await port.setFlowControl(FlowControl.None);
await port.setParity(Parity.None);
await port.setStopBits(StopBits.One);
await port.setTimeout(500);

Control Signals with Types

// Set control signals
await port.setRequestToSend(true);
await port.setDataTerminalReady(true);

// Alternative methods (writeRequestToSend and writeDataTerminalReady)
await port.writeRequestToSend(true);
await port.writeDataTerminalReady(true);

// Read control signals
const cts = await port.readClearToSend();
const dsr = await port.readDataSetReady();
const ri = await port.readRingIndicator();
const cd = await port.readCarrierDetect();

Buffer Management with Types

import { ClearBuffer } from "tauri-plugin-serialplugin";

// Check buffer status
const bytesToRead = await port.bytesToRead();
const bytesToWrite = await port.bytesToWrite();

// Clear buffers with type-safe enum
await port.clearBuffer(ClearBuffer.Input);
await port.clearBuffer(ClearBuffer.Output);
await port.clearBuffer(ClearBuffer.All);

// Break signal control
await port.setBreak();
await port.clearBreak();

Rust Usage

This plugin can also be used directly from Rust code in your Tauri backend. For complete API documentation, see docs.rs.

Here's how to use it:

Using Commands Directly

You can import and use the command functions directly from the plugin:

use tauri_plugin_serialplugin::commands::{
    available_ports, open, write, read, close, set_baud_rate,
    set_data_bits, set_flow_control, set_parity, set_stop_bits, set_timeout,
    write_request_to_send, write_data_terminal_ready,
    read_clear_to_send, read_data_set_ready,
    bytes_to_read, bytes_to_write, clear_buffer,
    set_break, clear_break
};
use tauri_plugin_serialplugin::state::{DataBits, FlowControl, Parity, StopBits, ClearBuffer};
use tauri::{AppHandle, State, Runtime};
use std::collections::HashMap;

#[tauri::command]
async fn rust_serial_example(
    app: AppHandle<tauri::Wry>,
    serial: State<'_, tauri_plugin_serialplugin::desktop_api::SerialPort<tauri::Wry>>
) -> Result<(), String> {
    // Get available ports
    let ports = available_ports(app.clone(), serial.clone())
        .map_err(|e| format!("Failed to get ports: {}", e))?;
    println!("Available ports: {:?}", ports);

    // Open a serial port
    let path = "COM1".to_string();
    let baud_rate = 9600;
    
    open(
        app.clone(),
        serial.clone(),
        path.clone(),
        baud_rate,
        Some(DataBits::Eight),
        Some(FlowControl::None),
        Some(Parity::None),
        Some(StopBits::One),
        Some(1000u64) // timeout in milliseconds
    ).map_err(|e| format!("Failed to open port: {}", e))?;

    // Write data
    let data = "Hello from Rust!".to_string();
    let bytes_written = write(app.clone(), serial.clone(), path.clone(), data)
        .map_err(|e| format!("Failed to write: {}", e))?;
    println!("Wrote {} bytes", bytes_written);

    // Read data
    let received_data = read(
        app.clone(),
        serial.clone(),
        path.clone(),
        Some(1000u64), // timeout
        Some(1024usize) // max bytes to read
    ).map_err(|e| format!("Failed to read: {}", e))?;
    println!("Received: {}", received_data);

    // Configure port settings
    set_baud_rate(app.clone(), serial.clone(), path.clone(), 115200)
        .map_err(|e| format!("Failed to set baud rate: {}", e))?;
    
    set_data_bits(app.clone(), serial.clone(), path.clone(), DataBits::Eight)
        .map_err(|e| format!("Failed to set data bits: {}", e))?;
    
    set_flow_control(app.clone(), serial.clone(), path.clone(), FlowControl::None)
        .map_err(|e| format!("Failed to set flow control: {}", e))?;
    
    set_parity(app.clone(), serial.clone(), path.clone(), Parity::None)
        .map_err(|e| format!("Failed to set parity: {}", e))?;
    
    set_stop_bits(app.clone(), serial.clone(), path.clone(), StopBits::One)
        .map_err(|e| format!("Failed to set stop bits: {}", e))?;

    // Set timeout
    set_timeout(app.clone(), serial.clone(), path.clone(), 1000u64)
        .map_err(|e| format!("Failed to set timeout: {}", e))?;

    // Control signals
    write_request_to_send(app.clone(), serial.clone(), path.clone(), true)
        .map_err(|e| format!("Failed to set RTS: {}", e))?;
    
    write_data_terminal_ready(app.clone(), serial.clone(), path.clone(), true)
        .map_err(|e| format!("Failed to set DTR: {}", e))?;

    // Read control signals
    let cts = read_clear_to_send(app.clone(), serial.clone(), path.clone())
        .map_err(|e| format!("Failed to read CTS: {}", e))?;
    println!("CTS: {}", cts);

    let dsr = read_data_set_ready(app.clone(), serial.clone(), path.clone())
        .map_err(|e| format!("Failed to read DSR: {}", e))?;
    println!("DSR: {}", dsr);

    // Buffer management
    let bytes_to_read = bytes_to_read(app.clone(), serial.clone(), path.clone())
        .map_err(|e| format!("Failed to get bytes to read: {}", e))?;
    println!("Bytes available to read: {}", bytes_to_read);

    let bytes_to_write = bytes_to_write(app.clone(), serial.clone(), path.clone())
        .map_err(|e| format!("Failed to get bytes to write: {}", e))?;
    println!("Bytes waiting to write: {}", bytes_to_write);

    // Clear buffers
    clear_buffer(app.clone(), serial.clone(), path.clone(), ClearBuffer::All)
        .map_err(|e| format!("Failed to clear buffer: {}", e))?;

    // Break signal
    set_break(app.clone(), serial.clone(), path.clone())
        .map_err(|e| format!("Failed to set break: {}", e))?;
    
    clear_break(app.clone(), serial.clone(), path.clone())
        .map_err(|e| format!("Failed to clear break: {}", e))?;

    // Close the port
    close(app, serial, path)
        .map_err(|e| format!("Failed to close port: {}", e))?;

    Ok(())
}

Advanced Rust Example with Error Handling

use tauri_plugin_serialplugin::commands::{
    available_ports, open, write, read, close, force_close, managed_ports, start_listening
};
use tauri_plugin_serialplugin::state::{DataBits, FlowControl, Parity, StopBits};
use tauri::{AppHandle, State};
use std::collections::HashMap;

#[tauri::command]
async fn advanced_serial_example(
    app: AppHandle<tauri::Wry>,
    serial: State<'_, tauri_plugin_serialplugin::desktop_api::SerialPort<tauri::Wry>>
) -> Result<(), String> {
    // Get available ports with error handling
    let ports = match available_ports(app.clone(), serial.clone()) {
        Ok(ports) => ports,
        Err(e) => {
            eprintln!("Failed to get available ports: {}", e);
            return Err("No serial ports available".to_string());
        }
    };

    if ports.is_empty() {
        return Err("No serial ports found".to_string());
    }

    // Use the first available port
    let port_path = ports.keys().next().unwrap().clone();
    println!("Using port: {}", port_path);

    // Open port with full configuration
    let open_result = open(
        app.clone(),
        serial.clone(),
        port_path.clone(),
        9600u32, // baud rate
        Some(DataBits::Eight),
        Some(FlowControl::None),
        Some(Parity::None),
        Some(StopBits::One),
        Some(5000u64) // 5 second timeout
    );

    match open_result {
        Ok(_) => println!("Port opened successfully"),
        Err(e) => {
            eprintln!("Failed to open port: {}", e);
            return Err(format!("Failed to open port {}: {}", port_path, e));
        }
    }

    // Start listening for data
    match start_listening(
        app.clone(),
        serial.clone(),
        port_path.clone(),
        Some(1000u64), // timeout
        Some(1024usize) // max bytes
    ) {
        Ok(_) => println!("Started listening"),
        Err(e) => {
            eprintln!("Failed to start listening: {}", e);
            // Continue anyway, we can still read manually
        }
    }

    // Send a command and read response
    let command = "AT\r\n".to_string();
    match write(app.clone(), serial.clone(), port_path.clone(), command) {
        Ok(bytes) => println!("Sent {} bytes", bytes),
        Err(e) => {
            eprintln!("Failed to write command: {}", e);
            return Err(format!("Write failed: {}", e));
        }
    }

    // Read response with timeout
    match read(
        app.clone(),
        serial.clone(),
        port_path.clone(),
        Some(2000u64), // 2 second timeout
        Some(512usize) // max 512 bytes
    ) {
        Ok(response) => println!("Response: {}", response),
        Err(e) => {
            eprintln!("Failed to read response: {}", e);
            return Err(format!("Read failed: {}", e));
        }
    }

    // Get managed ports
    let managed_ports = match managed_ports(app.clone(), serial.clone()) {
        Ok(ports) => ports,
        Err(e) => {
            eprintln!("Failed to get managed ports: {}", e);
            Vec::new()
        }
    };
    println!("Managed ports: {:?}", managed_ports);

    // Clean up
    let cleanup_result = close(app.clone(), serial.clone(), port_path.clone());
    match cleanup_result {
        Ok(_) => println!("Port closed successfully"),
        Err(e) => {
            eprintln!("Failed to close port: {}", e);
            // Try force close
            if let Err(e2) = force_close(app, serial, port_path) {
                eprintln!("Failed to force close port: {}", e2);
            }
        }
    }

    Ok(())
}

Binary Data Handling in Rust

use tauri_plugin_serialplugin::commands::{open, write_binary, read_binary, close};
use tauri_plugin_serialplugin::state::{DataBits, FlowControl, Parity, StopBits};
use tauri::{AppHandle, State};

#[tauri::command]
async fn binary_data_example(
    app: AppHandle<tauri::Wry>,
    serial: State<'_, tauri_plugin_serialplugin::desktop_api::SerialPort<tauri::Wry>>
) -> Result<(), String> {
    let port_path = "COM1".to_string();
    
    // Open port
    open(
        app.clone(),
        serial.clone(),
        port_path.clone(),
        115200u32,
        Some(DataBits::Eight),
        Some(FlowControl::None),
        Some(Parity::None),
        Some(StopBits::One),
        Some(1000u64)
    ).map_err(|e| format!("Failed to open port: {}", e))?;

    // Write binary data
    let binary_data = vec![0x48, 0x65, 0x6C, 0x6C, 0x6F]; // "Hello" in ASCII
    let bytes_written = write_binary(app.clone(), serial.clone(), port_path.clone(), binary_data)
        .map_err(|e| format!("Failed to write binary data: {}", e))?;
    println!("Wrote {} bytes of binary data", bytes_written);

    // Read binary data
    let received_data = read_binary(
        app.clone(),
        serial.clone(),
        port_path.clone(),
        Some(1000u64), // timeout
        Some(256usize) // max bytes
    ).map_err(|e| format!("Failed to read binary data: {}", e))?;
    
    println!("Received {} bytes: {:?}", received_data.len(), received_data);

    // Close port
    close(app, serial, port_path)
        .map_err(|e| format!("Failed to close port: {}", e))?;

    Ok(())
}

Using Commands vs Direct API

You have two ways to use the plugin in Rust:

Option 1: Using Commands (Recommended)

Import and use the command functions directly. These functions are documented in the docs.rs documentation:

use tauri_plugin_serialplugin::commands::{available_ports, open, write, read, close};
use tauri::{AppHandle, State};

#[tauri::command]
async fn my_serial_function(
    app: AppHandle<tauri::Wry>,
    serial: State<'_, tauri_plugin_serialplugin::desktop_api::SerialPort<tauri::Wry>>
) -> Result<(), String> {
    // Use command functions
    let ports = available_ports(app.clone(), serial.clone())?;
    open(app.clone(), serial.clone(), "COM1".to_string(), 9600, None, None, None, None, None)?;
    // ... rest of your code
}

Option 2: Using Direct API

Use the SerialPort methods directly:

use tauri::State;
use tauri_plugin_serialplugin::desktop_api::SerialPort;

#[tauri::command]
async fn my_serial_function(
    serial: State<'_, SerialPort<tauri::Wry>>
) -> Result<(), String> {
    // Use serial methods directly
    let ports = serial.available_ports()?;
    // ... rest of your code
}

Available Rust Types

The plugin provides the following Rust types for configuration:

use tauri_plugin_serialplugin::state::{
    DataBits,      // Five, Six, Seven, Eight
    FlowControl,   // None, Software, Hardware
    Parity,        // None, Odd, Even
    StopBits,      // One, Two
    ClearBuffer    // Input, Output, All
};

Complete Command Functions Reference

Here are all the available command functions you can import and use. For detailed documentation with examples, see the docs.rs documentation:

use tauri_plugin_serialplugin::commands::{
    // Port discovery
    available_ports,           // Get list of available ports
    available_ports_direct,    // Get ports using platform-specific commands
    managed_ports,             // Get list of currently managed ports
    
    // Connection management
    open,                      // Open a serial port
    close,                     // Close a serial port
    close_all,                 // Close all open ports
    force_close,               // Force close a port
    
    // Data transfer
    write,                     // Write string data
    write_binary,              // Write binary data
    read,                      // Read string data
    read_binary,               // Read binary data
    
    // Listening
    start_listening,           // Start listening for data
    stop_listening,            // Stop listening
    cancel_read,               // Cancel read operations
    
    // Port configuration
    set_baud_rate,             // Set baud rate
    set_data_bits,             // Set data bits
    set_flow_control,          // Set flow control
    set_parity,                // Set parity
    set_stop_bits,             // Set stop bits
    set_timeout,               // Set timeout
    
    // Control signals
    write_request_to_send,     // Set RTS signal
    write_data_terminal_ready, // Set DTR signal
    read_clear_to_send,        // Read CTS signal
    read_data_set_ready,       // Read DSR signal
    read_ring_indicator,       // Read RI signal
    read_carrier_detect,       // Read CD signal
    
    // Buffer management
    bytes_to_read,             // Get bytes available to read
    bytes_to_write,            // Get bytes waiting to write
    clear_buffer,              // Clear buffers
    
    // Break signal
    set_break,                 // Start break signal
    clear_break,               // Stop break signal
};

Command Function Signatures

All command functions follow this pattern:

pub fn function_name<R: Runtime>(
    app: AppHandle<R>,
    serial: State<'_, SerialPort<R>>,
    // ... additional parameters specific to the function
) -> Result<ReturnType, Error>

For example:

// Open port
pub fn open<R: Runtime>(
    app: AppHandle<R>,
    serial: State<'_, SerialPort<R>>,
    path: String,
    baud_rate: u32,
    data_bits: Option<DataBits>,
    flow_control: Option<FlowControl>,
    parity: Option<Parity>,
    stop_bits: Option<StopBits>,
    timeout: Option<u64>,
) -> Result<(), Error>

// Write data
pub fn write<R: Runtime>(
    app: AppHandle<R>,
    serial: State<'_, SerialPort<R>>,
    path: String,
    value: String,
) -> Result<usize, Error>

Error Messages

Port Discovery

"Failed to lock serialports mutex" - Error acquiring mutex lock when listing ports
"Invalid response format" - Invalid response format from plugin
"Plugin error: {error}" - Plugin execution error

Port Management

"Failed to acquire lock: {error}" - Error acquiring mutex lock
"Port '{path}' not found" - Port does not exist
"Serial port {path} is not open!" - Port is not open
"Failed to open serial port: {error}" - Error opening port
"Failed to clone serial port: {error}" - Error cloning port
"Failed to set short timeout: {error}" - Error setting timeout
"Failed to stop existing listener: {error}" - Error stopping existing listener
"Failed to join thread: {error}" - Error waiting for thread completion
"Failed to cancel serial port data reading: {error}" - Error canceling data reading

Data Operations

"Failed to write data: {error}" - Error writing data
"Failed to write binary data: {error}" - Error writing binary data
"Failed to read data: {error}" - Error reading data
"no data received within {timeout} ms" - Read timeout
"Failed to set timeout: {error}" - Error setting timeout

Port Configuration

"Failed to set baud rate: {error}" - Error setting baud rate
"Failed to set data bits: {error}" - Error setting data bits
"Failed to set flow control: {error}" - Error setting flow control
"Failed to set parity: {error}" - Error setting parity
"Failed to set stop bits: {error}" - Error setting stop bits

Control Signals

"Failed to set RTS: {error}" - Error setting RTS signal
"Failed to set DTR: {error}" - Error setting DTR signal
"Failed to read CTS: {error}" - Error reading CTS signal
"Failed to read DSR: {error}" - Error reading DSR signal
"Failed to read RI: {error}" - Error reading RI signal
"Failed to read CD: {error}" - Error reading CD signal
"Failed to set break: {error}" - Error setting break signal
"Failed to clear break: {error}" - Error clearing break signal

Buffer Management

"Failed to clear buffer: {error}" - Error clearing buffer
"Failed to get bytes to read: {error}" - Error getting bytes available to read
"Failed to get bytes to write: {error}" - Error getting bytes waiting to write

Permissions

Below is a list of all permissions the plugin supports. Granting or denying them allows fine-grained control over what your application can do with serial ports.

Permission	Description
`serialplugin:allow-available-ports`	Allows listing of available serial ports
`serialplugin:deny-available-ports`	Denies listing of available serial ports
`serialplugin:allow-cancel-read`	Allows canceling of read operations
`serialplugin:deny-cancel-read`	Denies canceling of read operations
`serialplugin:allow-close`	Allows closing of serial ports
`serialplugin:deny-close`	Denies closing of serial ports
`serialplugin:allow-close-all`	Allows closing of all open serial ports
`serialplugin:deny-close-all`	Denies closing of all open serial ports
`serialplugin:allow-force-close`	Allows forcefully closing of serial ports
`serialplugin:deny-force-close`	Denies forcefully closing of serial ports
`serialplugin:allow-open`	Allows opening of serial ports
`serialplugin:deny-open`	Denies opening of serial ports
`serialplugin:allow-read`	Allows reading data from serial ports
`serialplugin:deny-read`	Denies reading data from serial ports
`serialplugin:allow-read-binary`	Allows reading binary data from serial ports
`serialplugin:deny-read-binary`	Denies reading binary data from serial ports
`serialplugin:allow-write`	Allows writing data to serial ports
`serialplugin:deny-write`	Denies writing data to serial ports
`serialplugin:allow-write-binary`	Allows writing binary data to serial ports
`serialplugin:deny-write-binary`	Denies writing binary data to serial ports
`serialplugin:allow-available-ports-direct`	Enables the `available_ports_direct` command without any pre-configured scope
`serialplugin:deny-available-ports-direct`	Denies the `available_ports_direct` command without any pre-configured scope
`serialplugin:allow-set-baud-rate`	Allows changing the baud rate of serial ports
`serialplugin:deny-set-baud-rate`	Denies changing the baud rate of serial ports
`serialplugin:allow-set-data-bits`	Allows changing the data bits configuration
`serialplugin:deny-set-data-bits`	Denies changing the data bits configuration
`serialplugin:allow-set-flow-control`	Allows changing the flow control mode
`serialplugin:deny-set-flow-control`	Denies changing the flow control mode
`serialplugin:allow-set-parity`	Allows changing the parity checking mode
`serialplugin:deny-set-parity`	Denies changing the parity checking mode
`serialplugin:allow-set-stop-bits`	Allows changing the stop bits configuration
`serialplugin:deny-set-stop-bits`	Denies changing the stop bits configuration
`serialplugin:allow-set-timeout`	Allows changing the timeout duration
`serialplugin:deny-set-timeout`	Denies changing the timeout duration
`serialplugin:allow-write-rts`	Allows setting the RTS (Request To Send) control signal
`serialplugin:deny-write-rts`	Denies setting the RTS control signal
`serialplugin:allow-write-dtr`	Allows setting the DTR (Data Terminal Ready) control signal
`serialplugin:deny-write-dtr`	Denies setting the DTR control signal
`serialplugin:allow-read-cts`	Allows reading the CTS (Clear To Send) control signal state
`serialplugin:deny-read-cts`	Denies reading the CTS control signal state
`serialplugin:allow-read-dsr`	Allows reading the DSR (Data Set Ready) control signal state
`serialplugin:deny-read-dsr`	Denies reading the DSR control signal state
`serialplugin:allow-read-ri`	Allows reading the RI (Ring Indicator) control signal state
`serialplugin:deny-read-ri`	Denies reading the RI control signal state
`serialplugin:allow-read-cd`	Allows reading the CD (Carrier Detect) control signal state
`serialplugin:deny-read-cd`	Denies reading the CD control signal state
`serialplugin:allow-bytes-to-read`	Allows checking the number of bytes available to read
`serialplugin:deny-bytes-to-read`	Denies checking the number of bytes available to read
`serialplugin:allow-bytes-to-write`	Allows checking the number of bytes waiting to be written
`serialplugin:deny-bytes-to-write`	Denies checking the number of bytes waiting to be written
`serialplugin:allow-clear-buffer`	Allows clearing input/output buffers
`serialplugin:deny-clear-buffer`	Denies clearing input/output buffers
`serialplugin:allow-set-break`	Allows starting break signal transmission
`serialplugin:deny-set-break`	Denies starting break signal transmission
`serialplugin:allow-clear-break`	Allows stopping break signal transmission
`serialplugin:deny-clear-break`	Denies stopping break signal transmission
`serialplugin:allow-start-listening`	Allows starting automatic port monitoring and data listening
`serialplugin:deny-start-listening`	Denies starting automatic port monitoring and data listening
`serialplugin:allow-stop-listening`	Allows stopping automatic port monitoring and data listening
`serialplugin:deny-stop-listening`	Denies stopping automatic port monitoring and data listening

Granting All Permissions (Example)

"permissions": [
  "core:default",
  "serialplugin:default",
  "serialplugin:allow-available-ports",
  "serialplugin:allow-cancel-read",
  "serialplugin:allow-close",
  "serialplugin:allow-close-all",
  "serialplugin:allow-force-close",
  "serialplugin:allow-open",
  "serialplugin:allow-read",
  "serialplugin:allow-write",
  "serialplugin:allow-write-binary",
  "serialplugin:allow-available-ports-direct",
  "serialplugin:allow-set-baud-rate",
  "serialplugin:allow-set-data-bits",
  "serialplugin:allow-set-flow-control",
  "serialplugin:allow-set-parity",
  "serialplugin:allow-set-stop-bits",
  "serialplugin:allow-set-timeout",
  "serialplugin:allow-write-rts",
  "serialplugin:allow-write-dtr",
  "serialplugin:allow-read-cts",
  "serialplugin:allow-read-dsr",
  "serialplugin:allow-read-ri",
  "serialplugin:allow-read-cd",
  "serialplugin:allow-bytes-to-read",
  "serialplugin:allow-bytes-to-write",
  "serialplugin:allow-clear-buffer",
  "serialplugin:allow-set-break",
  "serialplugin:allow-clear-break",
  "serialplugin:allow-start-listening",
  "serialplugin:allow-stop-listening"
]

API Reference

Port Discovery

class SerialPort {
  /**
   * Lists all available serial ports on the system
   * @returns {Promise<{[key: string]: PortInfo}>} Map of port names to port information
   * @example
   * const ports = await SerialPort.available_ports();
   * console.log(ports);
   */
  static async available_ports(): Promise<{ [key: string]: PortInfo }>;

  /**
   * Lists ports using platform-specific commands for enhanced detection
   * @returns {Promise<{[key: string]: PortInfo}>} Map of port names to port information
   * @example
   * const ports = await SerialPort.available_ports_direct();
   */
  static async available_ports_direct(): Promise<{ [key: string]: PortInfo }>;

  /**
   * @description Lists all managed serial ports (ports that are currently open and managed by the application).
   * @returns {Promise<string[]>} A promise that resolves to an array of port paths (names).
   */
  static async managed_ports(): Promise<string[]>;
}

Connection Management

class SerialPort {
  /**
   * Opens the serial port with specified configuration
   * @returns {Promise<void>}
   * @throws {Error} If port is already open or invalid configuration
   * @example
   * const port = new SerialPort({ path: "COM1", baudRate: 9600 });
   * await port.open();
   */
  async open(): Promise<void>;

  /**
   * Closes the serial port connection
   * @returns {Promise<void>}
   * @throws {Error} If port is not open
   * @example
   * await port.close();
   */
  async close(): Promise<void>;

  /**
   * Starts listening for data on the serial port
   * @returns {Promise<void>} A promise that resolves when listening starts
   * @throws {Error} If starting listener fails or port is not open
   * @example
   * await port.startListening();
   *
   * // Listen for data events
   * port.listen((data) => {
   *   console.log("Data received:", data);
   * });
   */
  async startListening(): Promise<void>;

  /**
   * Stops listening for data on the serial port
   * @returns {Promise<void>} A promise that resolves when listening stops
   * @throws {Error} If stopping listener fails or port is not open
   * @example
   * await port.stopListening();
   */
  async stopListening(): Promise<void>;

  /**
   * Forces a serial port to close regardless of its state
   * @param {string} path Port path to force close
   * @returns {Promise<void>}
   * @example
   * await SerialPort.forceClose("COM1");
   */
  static async forceClose(path: string): Promise<void>;

  /**
   * Closes all open serial port connections
   * @returns {Promise<void>}
   * @example
   * await SerialPort.closeAll();
   */
  static async closeAll(): Promise<void>;
}

Data Transfer

class SerialPort {
  /**
   * Writes string data to the serial port
   * @param {string} data Data to write
   * @returns {Promise<number>} Number of bytes written
   * @throws {Error} If write fails or port is not open
   * @example
   * const bytesWritten = await port.write("Hello");
   */
  async write(data: string): Promise<number>;

  /**
   * Reads data from the serial port
   * @param {ReadOptions} [options] Read options
   * @returns {Promise<string>} A promise that resolves to a string
   */
  async read(options?: ReadOptions): Promise<string>;

  /**
   * Reads binary data from the serial port
   * @param {ReadOptions} [options] Read options
   * @returns {Promise<Uint8Array>} A promise that resolves with binary data
   */
  async readBinary(options?: ReadOptions): Promise<Uint8Array>;

  /**
   * Writes binary data to the serial port
   * @param {Uint8Array | number[]} data Binary data to write
   * @returns {Promise<number>} Number of bytes written
   * @throws {Error} If write fails or port is not open
   * @example
   * const data = new Uint8Array([0x01, 0x02, 0x03]);
   * const bytesWritten = await port.writeBinary(data);
   */
  async writeBinary(data: Uint8Array | number[]): Promise<number>;

  /**
   * Sets up a listener for incoming data
   * @param {(data: string | Uint8Array) => void} callback Function to handle received data
   * @param {boolean} [decode=true] Whether to decode data as string (true) or return raw bytes (false)
   * @returns {Promise<UnlistenFn>} A promise that resolves to an unlisten function
   * @example
   * const unsubscribe = await port.listen((data) => {
   *   console.log("Received:", data);
   * });
   * 
   * // Later, to stop listening:
   * unsubscribe();
   */
  async listen(callback: (data: string | Uint8Array) => void, decode?: boolean): Promise<UnlistenFn>;

  /**
   * Cancels listening for serial port data (does not affect disconnect listeners)
   * @returns {Promise<void>} A promise that resolves when listening is cancelled
   * @example
   * await port.cancelListen();
   */
  async cancelListen(): Promise<void>;
}

Port Configuration

class SerialPort {
  /**
   * Sets the baud rate
   * @param {number} baudRate Speed in bits per second
   * @returns {Promise<void>}
   * @example
   * await port.setBaudRate(115200);
   */
  async setBaudRate(baudRate: number): Promise<void>;

  /**
   * Sets the number of data bits
   * @param {DataBits} dataBits Number of bits per character (5-8)
   * @returns {Promise<void>}
   * @example
   * await port.setDataBits(DataBits.Eight);
   */
  async setDataBits(dataBits: DataBits): Promise<void>;

  /**
   * Sets the flow control mode
   * @param {FlowControl} flowControl Flow control setting
   * @returns {Promise<void>}
   * @example
   * await port.setFlowControl(FlowControl.Hardware);
   */
  async setFlowControl(flowControl: FlowControl): Promise<void>;

  /**
   * Sets the parity checking mode
   * @param {Parity} parity Parity checking mode
   * @returns {Promise<void>}
   * @example
   * await port.setParity(Parity.None);
   */
  async setParity(parity: Parity): Promise<void>;

  /**
   * Sets the number of stop bits
   * @param {StopBits} stopBits Number of stop bits
   * @returns {Promise<void>}
   * @example
   * await port.setStopBits(StopBits.One);
   */
  async setStopBits(stopBits: StopBits): Promise<void>;

  /**
   * Sets the timeout for read operations
   * @param {number} timeout Timeout value in milliseconds
   * @returns {Promise<void>}
   * @example
   * await port.setTimeout(1000);
   */
  async setTimeout(timeout: number): Promise<void>;
}

Control Signals

class SerialPort {
  /**
   * Sets the RTS (Request to Send) signal
   * @param {boolean} level Signal level (true = high, false = low)
   * @returns {Promise<void>}
   * @example
   * await port.writeRequestToSend(true);
   */
  async writeRequestToSend(level: boolean): Promise<void>;

  /**
   * Sets the DTR (Data Terminal Ready) signal
   * @param {boolean} level Signal level (true = high, false = low)
   * @returns {Promise<void>}
   * @example
   * await port.writeDataTerminalReady(true);
   */
  async writeDataTerminalReady(level: boolean): Promise<void>;

  /**
   * Alternative method to set RTS signal
   * @param {boolean} value Signal level (true = high, false = low)
   * @returns {Promise<void>}
   * @example
   * await port.setRequestToSend(true);
   */
  async setRequestToSend(value: boolean): Promise<void>;

  /**
   * Alternative method to set DTR signal
   * @param {boolean} value Signal level (true = high, false = low)
   * @returns {Promise<void>}
   * @example
   * await port.setDataTerminalReady(true);
   */
  async setDataTerminalReady(value: boolean): Promise<void>;

  /**
   * Reads the CTS (Clear to Send) signal state
   * @returns {Promise<boolean>} Signal state
   * @example
   * const cts = await port.readClearToSend();
   */
  async readClearToSend(): Promise<boolean>;

  /**
   * Reads the DSR (Data Set Ready) signal state
   * @returns {Promise<boolean>} Signal state
   * @example
   * const dsr = await port.readDataSetReady();
   */
  async readDataSetReady(): Promise<boolean>;

  /**
   * Reads the RI (Ring Indicator) signal state
   * @returns {Promise<boolean>} Signal state
   * @example
   * const ri = await port.readRingIndicator();
   */
  async readRingIndicator(): Promise<boolean>;

  /**
   * Reads the CD (Carrier Detect) signal state
   * @returns {Promise<boolean>} Signal state
   * @example
   * const cd = await port.readCarrierDetect();
   */
  async readCarrierDetect(): Promise<boolean>;
}

Buffer Management

class SerialPort {
  /**
   * Gets number of bytes available to read
   * @returns {Promise<number>} Number of bytes in read buffer
   * @example
   * const available = await port.bytesToRead();
   */
  async bytesToRead(): Promise<number>;

  /**
   * Gets number of bytes waiting to be written
   * @returns {Promise<number>} Number of bytes in write buffer
   * @example
   * const pending = await port.bytesToWrite();
   */
  async bytesToWrite(): Promise<number>;

  /**
   * Clears the specified buffer
   * @param {ClearBuffer} buffer Buffer to clear
   * @returns {Promise<void>}
   * @example
   * await port.clearBuffer(ClearBuffer.Input);
   */
  async clearBuffer(buffer: ClearBuffer): Promise<void>;

  /**
   * Sets the break signal
   * @returns {Promise<void>}
   * @example
   * await port.setBreak();
   */
  async setBreak(): Promise<void>;

  /**
   * Clears the break signal
   * @returns {Promise<void>}
   * @example
   * await port.clearBreak();
   */
  async clearBreak(): Promise<void>;
}

Auto-Reconnect Management

class SerialPort {
  /**
   * Enables auto-reconnect functionality
   * @param {Object} options Auto-reconnect configuration options
   * @param {number} [options.interval=5000] Reconnection interval in milliseconds
   * @param {number | null} [options.maxAttempts=10] Maximum number of reconnection attempts (null for infinite)
   * @param {Function} [options.onReconnect] Callback function called on each reconnection attempt
   * @returns {Promise<void>}
   * @example
   * await port.enableAutoReconnect({
   *   interval: 3000,
   *   maxAttempts: 5,
   *   onReconnect: (success, attempt) => {
   *     console.log(`Reconnect attempt ${attempt}: ${success ? 'success' : 'failed'}`);
   *   }
   * });
   */
  async enableAutoReconnect(options?: {
    interval?: number;
    maxAttempts?: number | null;
    onReconnect?: (success: boolean, attempt: number) => void;
  }): Promise<void>;

  /**
   * Disables auto-reconnect functionality
   * @returns {Promise<void>}
   * @example
   * await port.disableAutoReconnect();
   */
  async disableAutoReconnect(): Promise<void>;

  /**
   * Gets auto-reconnect status and configuration
   * @returns {Object} Auto-reconnect information
   * @example
   * const info = port.getAutoReconnectInfo();
   * console.log('Auto-reconnect enabled:', info.enabled);
   * console.log('Current attempts:', info.currentAttempts);
   */
  getAutoReconnectInfo(): {
    enabled: boolean;
    interval: number;
    maxAttempts: number | null;
    currentAttempts: number;
    hasCallback: boolean;
  };

  /**
   * Manually triggers a reconnection attempt
   * @returns {Promise<boolean>} A promise that resolves to true if reconnection was successful
   * @example
   * const success = await port.manualReconnect();
   * if (success) {
   *   console.log('Manual reconnection successful');
   * }
   */
  async manualReconnect(): Promise<boolean>;
}

Common Use Cases

Reading Sensor Data

const port = new SerialPort({
  path: "COM1",
  baudRate: 9600
});

await port.open();
await port.listen((data) => {
  const sensorValue = parseFloat(data);
  console.log("Sensor reading:", sensorValue);
});

Binary Protocol Communication

const port = new SerialPort({
  path: "COM1",
  baudRate: 115200
});

await port.open();

// Send command
const command = new Uint8Array([0x02, 0x01, 0x03]);
await port.writeBinary(command);

// Read response (raw bytes)
await port.listen((data) => {
  const response = data instanceof Uint8Array ? data : new Uint8Array();
  console.log("Response:", response);
}, false);

Modbus Communication

const port = new SerialPort({
   path: "COM1",
   baudRate: 9600,
   dataBits: DataBits.Eight,
   stopBits: StopBits.One,
   parity: Parity.None
});

await port.open();

function createModbusRequest(address: number, length: number): Uint8Array {
   return new Uint8Array([
      0x01, // Device ID
      0x03, // Function code: Read Holding Registers
      address >> 8, address & 0xFF,
      length >> 8, length & 0xFF
   ]);
}

// Send Modbus request
const request = createModbusRequest(0x1000, 10);
await port.writeBinary(request);

Auto-Reconnect for Reliable Communication

const port = new SerialPort({
  path: "COM1",
  baudRate: 9600
});

await port.open();

// Enable auto-reconnect with custom settings
await port.enableAutoReconnect({
  interval: 3000,        // Try to reconnect every 3 seconds
  maxAttempts: 5,        // Maximum 5 attempts
  onReconnect: (success, attempt) => {
    if (success) {
      console.log(`Reconnected successfully on attempt ${attempt}`);
    } else {
      console.log(`Reconnection attempt ${attempt} failed`);
    }
  }
});

// Set up data listener
const unsubscribe = await port.listen((data) => {
  console.log("Received data:", data);
});

// The port will automatically reconnect if disconnected
// You can also manually trigger reconnection
const success = await port.manualReconnect();
if (success) {
  console.log("Manual reconnection successful");
}

// Check auto-reconnect status
const info = port.getAutoReconnectInfo();
console.log("Auto-reconnect enabled:", info.enabled);
console.log("Current attempts:", info.currentAttempts);

// Disable auto-reconnect when no longer needed
await port.disableAutoReconnect();

Android Setup

To use this plugin on Android, you need to add the JitPack repository to your project's build.gradle.kts file located at /src-tauri/gen/android/build.gradle.kts. Below is an example of how to configure it:

buildscript {
    repositories {
        // ...
        maven { url = uri("https://jitpack.io") }
    }
    // ...
}

allprojects {
    repositories {
        // ...
        maven { url = uri("https://jitpack.io") }
    }
}

Contributing

Pull requests are welcome! Please read our contributing guidelines before you start.

Development Setup

git clone https://github.com/s00d/tauri-plugin-serialplugin.git
cd tauri-plugin-serialplugin

pnpm i
pnpm run build
pnpm run playground

Testing

For testing applications without physical hardware, you can use a mock implementation of the serial port. The mock port emulates all functions of a real port and allows testing the application without physical devices.

Using Mock Port

use tauri_plugin_serialplugin::tests::mock::MockSerialPort;

// Create a mock port
let mock_port = MockSerialPort::new();

// Configure port settings
mock_port.set_baud_rate(9600).unwrap();
mock_port.set_data_bits(serialport::DataBits::Eight).unwrap();
mock_port.set_flow_control(serialport::FlowControl::None).unwrap();
mock_port.set_parity(serialport::Parity::None).unwrap();
mock_port.set_stop_bits(serialport::StopBits::One).unwrap();

// Write data
mock_port.write("Test data".as_bytes()).unwrap();

// Read data
let mut buffer = [0u8; 1024];
let bytes_read = mock_port.read(&mut buffer).unwrap();
let data = String::from_utf8_lossy(&buffer[..bytes_read]);
assert_eq!(data, "Test data");

Mock Port Features

Complete emulation of all real port functions
Built-in buffer for data storage
Control signal emulation (RTS, DTR, CTS, DSR)
Support for parallel operation testing
No additional software required
Works on all platforms

Application Testing Example

#[test]
fn test_serial_communication() {
    let app = create_test_app();
    let serial_port = SerialPort::new(app.handle().clone());
    app.manage(serial_port);

    // Open mock port
    app.state::<SerialPort<MockRuntime>>().open(
        "COM1".to_string(),
        9600,
        Some(DataBits::Eight),
        Some(FlowControl::None),
        Some(Parity::None),
        Some(StopBits::One),
        Some(1000),
    ).unwrap();

    // Test write and read operations
    app.state::<SerialPort<MockRuntime>>().write(
        "COM1".to_string(),
        "Test data".to_string(),
    ).unwrap();

    let data = app.state::<SerialPort<MockRuntime>>().read(
        "COM1".to_string(),
        Some(1000),
        Some(1024),
    ).unwrap();
    assert_eq!(data, "Test data");

    // Test port settings
    app.state::<SerialPort<MockRuntime>>().set_baud_rate(
        "COM1".to_string(),
        115200,
    ).unwrap();

    // Close port
    app.state::<SerialPort<MockRuntime>>().close("COM1".to_string()).unwrap();
}

Implementing Your Own Mock Port

You can implement your own mock port by implementing the SerialPort trait. Here's a basic example of how to create a custom mock port:

use std::io::{self, Read, Write};
use serialport::{self, SerialPort};
use std::time::Duration;

struct CustomMockPort {
    buffer: Vec<u8>,
    baud_rate: u32,
    data_bits: serialport::DataBits,
    flow_control: serialport::FlowControl,
    parity: serialport::Parity,
    stop_bits: serialport::StopBits,
    timeout: Duration,
}

impl CustomMockPort {
    fn new() -> Self {
        Self {
            buffer: Vec::new(),
            baud_rate: 9600,
            data_bits: serialport::DataBits::Eight,
            flow_control: serialport::FlowControl::None,
            parity: serialport::Parity::None,
            stop_bits: serialport::StopBits::One,
            timeout: Duration::from_millis(1000),
        }
    }
}

// Implement Read trait for reading data
impl Read for CustomMockPort {
    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
        let len = std::cmp::min(buf.len(), self.buffer.len());
        if len > 0 {
            buf[..len].copy_from_slice(&self.buffer[..len]);
            self.buffer.drain(..len);
        }
        Ok(len)
    }
}

// Implement Write trait for writing data
impl Write for CustomMockPort {
    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
        self.buffer.extend_from_slice(buf);
        Ok(buf.len())
    }

    fn flush(&mut self) -> io::Result<()> {
        Ok(())
    }
}

// Implement SerialPort trait for port configuration
impl SerialPort for CustomMockPort {
    fn name(&self) -> Option<String> {
        Some("CUSTOM_PORT".to_string())
    }

    fn baud_rate(&self) -> serialport::Result<u32> {
        Ok(self.baud_rate)
    }

    fn data_bits(&self) -> serialport::Result<serialport::DataBits> {
        Ok(self.data_bits)
    }

    // ... implement other required methods ...
}

For a complete implementation example, see the mock port implementation in the plugin's test directory: src/tests/mock.rs

The example includes:

Full implementation of all required traits
Buffer management for read/write operations
Control signal emulation
Port configuration handling
Error handling
Thread safety considerations

You can use this implementation as a reference when creating your own mock port with custom behavior for specific testing scenarios.

Partners

If you find this plugin valuable and would like to support further development, feel free to donate via DonationAlerts. Any contribution is greatly appreciated!

tauri-plugin-serialplugin 2.16.0

Tauri Plugin — SerialPort

Table of Contents

Installation

Prerequisites

Installation Methods

Basic Usage

TypeScript Support

Available Types

Type Definitions

Configuration Example with Types

Control Signals with Types

Buffer Management with Types

Rust Usage

Using Commands Directly

Advanced Rust Example with Error Handling

Binary Data Handling in Rust

Using Commands vs Direct API

Option 1: Using Commands (Recommended)

Option 2: Using Direct API

Available Rust Types

Complete Command Functions Reference

Command Function Signatures

Error Messages

Port Discovery

Port Management

Data Operations

Port Configuration

Control Signals

Buffer Management

Permissions

Granting All Permissions (Example)

API Reference

Port Discovery

Connection Management

Data Transfer

Port Configuration

Control Signals

Buffer Management

Auto-Reconnect Management

Common Use Cases

Reading Sensor Data

Binary Protocol Communication

Modbus Communication

Auto-Reconnect for Reliable Communication

Android Setup

Contributing

Development Setup

Testing

Using Mock Port

Mock Port Features

Application Testing Example

Implementing Your Own Mock Port

Partners

License