### Start Rttys Server with Minimal Configuration

Source: https://context7.com/zhaojh329/rttys/llms.txt

Starts the Rttys server using default ports for device and user connections. No additional configuration is required for basic operation.

```bash
./rttys
```

--------------------------------

### Start Rttys Server with Production Configuration

Source: https://context7.com/zhaojh329/rttys/llms.txt

Starts the Rttys server with a comprehensive set of production-ready flags, including custom ports, authentication tokens, SSL certificates, and webhook URLs. Ensure all specified paths for certificates are correct.

```bash
./rttys \
  --addr-dev    :5912 \
  --addr-user   :5913 \
  --token       a1d4cdb1a3cd6a0e94aa3599afcddcf5 \
  --password    mysecret \
  --sslcert     /etc/rttys/server.crt \
  --sslkey      /etc/rttys/server.key \
  --cacert      /etc/rttys/ca.crt \
  --dev-hook-url  http://127.0.0.1:8080/rttys-dev-hook \
  --user-hook-url http://127.0.0.1:8080/rttys-user-hook \
  --log-level   info \
  --verbose
```

--------------------------------

### Start Rttys Server with Configuration File

Source: https://context7.com/zhaojh329/rttys/llms.txt

Launches the Rttys server using a specified YAML configuration file. This method is recommended for managing complex configurations.

```bash
./rttys -c /etc/rttys/rttys.conf
```

--------------------------------

### GET /devs?group=<group>

Source: https://context7.com/zhaojh329/rttys/llms.txt

Lists all devices within a specified group along with their metadata.

```APIDOC
## GET /devs?group=<group>

### Description
List all devices in a group with their metadata.

### Method
GET

### Endpoint
`http://localhost:5913/devs?group=<group>`

### Parameters
#### Query Parameters
- **group** (string) - Optional - The name of the group to list devices from. If omitted, lists devices from the default group.

### Response
#### Success Response (200)
- **devices** (array of objects) - A list of devices in the specified group, each with metadata.
  - **group** (string) - The group the device belongs to.
  - **id** (string) - The unique identifier of the device.
  - **description** (string) - A description of the device.
  - **connected** (integer) - The duration in seconds the device has been connected.
  - **uptime** (integer) - The uptime of the device in seconds.
  - **proto** (integer) - The protocol version used by the device.
  - **ipaddr** (string) - The IP address of the device.

#### Response Example
```json
[
  {
    "group": "factory",
    "id": "device001",
    "description": "Raspberry Pi 4",
    "connected": 3721,
    "uptime": 86400,
    "proto": 5,
    "ipaddr": "192.168.1.50"
  }
]
```
```

--------------------------------

### Rttys Server Configuration File Example

Source: https://context7.com/zhaojh329/rttys/llms.txt

A sample YAML configuration file for Rttys, demonstrating how to set various parameters such as network addresses, authentication tokens, passwords, webhook URLs, and SSL certificates. CLI flags will override these settings.

```yaml
# rttys.conf
addr-dev:   :5912
addr-user:  :5913

# Token that every rtty client must present on registration
token: a1d4cdb1a3cd6a0e94aa3599afcddcf5

# Web UI password (empty = no auth required)
password: rttys

# Disable auth for requests originating on loopback
local-auth: false

# Allow cross-origin requests
allow-origins: true

# HTTP proxy redirect URL (leave empty for auto-detect)
http-proxy-redir-url:
http-proxy-redir-domain:

# Webhook URLs
dev-hook-url:  http://127.0.0.1:8080/rttys-dev-hook
user-hook-url: http://127.0.0.1:8080/rttys-user-hook

# TLS for the device listener
sslcert: /etc/rttys/server.crt
sslkey:  /etc/rttys/server.key
cacert:  /etc/rttys/ca.crt   # enables mTLS

```

--------------------------------

### List Devices in a Group (GET /devs)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Retrieves a list of devices within a specified group, including their metadata such as connection status, uptime, and IP address. If no group is specified, it defaults to the empty-string group. This endpoint requires authentication.

```bash
# All devices in default group
curl -s -b cookies.txt "http://localhost:5913/devs"
```

```bash
# Devices in the "factory" group
curl -s -b cookies.txt "http://localhost:5913/devs?group=factory"
# [
#   {
#     "group": "factory",
#     "id": "device001",
#     "description": "Raspberry Pi 4",
#     "connected": 3721,
#     "uptime": 86400,
#     "proto": 5,
#     "ipaddr": "192.168.1.50"
#   }
# ]
```

--------------------------------

### GET /groups

Source: https://context7.com/zhaojh329/rttys/llms.txt

Lists all active device groups. The default empty-string group is always included.

```APIDOC
## GET /groups

### Description
List all active device groups (always includes the default empty-string group).

### Method
GET

### Endpoint
`http://localhost:5913/groups`

### Response
#### Success Response (200)
- **groups** (array of strings) - A list of active device group names.

#### Response Example
```json
["","factory","warehouse","datacenter"]
```
```

--------------------------------

### Check Rttys Server Version

Source: https://context7.com/zhaojh329/rttys/llms.txt

Retrieves the currently installed version of the Rttys server binary. This is useful for verifying the deployment or troubleshooting compatibility issues.

```bash
./rttys --version
```

--------------------------------

### Create a New Branch

Source: https://github.com/zhaojh329/rttys/blob/master/CONTRIBUTING.md

Create a new branch for your changes. The branch name 'rttys-1-fix' is an example; you can choose any descriptive name.

```bash
git checkout -b "rttys-1-fix"
```

--------------------------------

### GET /counts

Source: https://context7.com/zhaojh329/rttys/llms.txt

Retrieves the total number of currently connected devices across all groups.

```APIDOC
## GET /counts

### Description
Return the total number of currently connected devices across all groups.

### Method
GET

### Endpoint
`http://localhost:5913/counts`

### Response
#### Success Response (200)
- **count** (integer) - The total number of connected devices.

#### Response Example
```json
{
  "count": 3
}
```
```

--------------------------------

### Sign Out from Rttys API (GET /signout)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Invalidates the current user session by sending a GET request to the /signout endpoint. This requires an active session cookie.

```bash
curl -s -b cookies.txt http://localhost:5913/signout
# HTTP 200
```

--------------------------------

### Get Total Connected Device Count (GET /counts)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Retrieves the total number of currently connected Rttys devices across all configured groups. This endpoint requires authentication.

```bash
curl -s -b cookies.txt http://localhost:5913/counts
# {"count":3}
```

--------------------------------

### GET /signout

Source: https://context7.com/zhaojh329/rttys/llms.txt

Invalidates the current user session.

```APIDOC
## GET /signout

### Description
Invalidate the current session.

### Method
GET

### Endpoint
`http://localhost:5913/signout`

### Response
#### Success Response (200)
- **Success**

#### Response Example
```
HTTP 200
```
```

--------------------------------

### List All Active Device Groups (GET /groups)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Retrieves a list of all active device groups managed by the Rttys server. The default empty-string group is always included. This endpoint requires authentication.

```bash
curl -s -b cookies.txt http://localhost:5913/groups
# ["","factory","warehouse","datacenter"]
```

--------------------------------

### GET /alive

Source: https://context7.com/zhaojh329/rttys/llms.txt

Checks if the current session is still valid. Useful for frontend polling.

```APIDOC
## GET /alive

### Description
Check if the current session is still valid (useful for frontend polling).

### Method
GET

### Endpoint
`http://localhost:5913/alive`

### Response
#### Success Response (200)
- **Authenticated**

#### Response Example
```
200 = authenticated
```

#### Error Response (401)
- **Session expired or missing**

#### Error Example
```
401
```
```

--------------------------------

### Check Rttys API Session Status (GET /alive)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Checks if the current session is still valid by polling the /alive endpoint. This is useful for frontend applications to maintain user authentication status.

```bash
curl -s -o /dev/null -w "%{http_code}" -b cookies.txt http://localhost:5913/alive
# 200 = authenticated, 401 = session expired or missing
```

--------------------------------

### Performance Profiling with pprof (Bash)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Enable and use the Go pprof HTTP endpoint for live performance profiling of RTTYS.

```bash
./rttys --pprof localhost:6060

# CPU profile (30 seconds)
go tool pprof http://localhost:6060/debug/pprof/profile?seconds=30

# Heap snapshot
go tool pprof http://localhost:6060/debug/pprof/heap

# Goroutine dump
curl http://localhost:6060/debug/pprof/goroutine?debug=1

# All available endpoints
curl http://localhost:6060/debug/pprof/
```

--------------------------------

### User Hook Integration

Source: https://context7.com/zhaojh329/rttys/llms.txt

Set up a webhook that is invoked when a user attempts to access a device via `/connect/:devid`, `/cmd/:devid`, `/web/`, or `/web2/`. Returning HTTP 200 permits access.

```APIDOC
## User Hook (`user-hook-url`) — `GET`

### Description
Called when a user accesses `/connect/:devid`, `/cmd/:devid`, `/web/`, or `/web2/`. Rttys forwards all original request headers plus three extra headers. Return HTTP 200 to allow access.

### Method
GET

### Endpoint
`/rttys-user-hook`

### Headers
RTTYS forwards original headers and adds the following:
- **X-Rttys-Hook** (string) - Indicates if this is a hook request (e.g., "true").
- **X-Original-Method** (string) - The original HTTP method of the user's request (e.g., "GET", "POST").
- **X-Original-URL** (string) - The original URL path requested by the user (e.g., "/connect/device001").
- **Authorization** (string) - The original authorization header from the user's request.

### Response
#### Success Response (200)
Returns an empty body to allow access.

#### Error Response (403)
Returns an empty body to block access if the provided token is invalid.
```

--------------------------------

### TLS/mTLS for Device Connections (Bash)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Secure RTTYS device listener with TLS. Use `--cacert` to enforce client certificate authentication (mTLS).

```bash
# Generate CA + server cert (self-signed example)
openssl genrsa -out ca.key 4096
openssl req -x509 -new -nodes -key ca.key -sha256 -days 3650 \
  -out ca.crt -subj "/CN=rttys-ca"

openssl genrsa -out server.key 2048
openssl req -new -key server.key -out server.csr -subj "/CN=rttys-server"
openssl x509 -req -in server.csr -CA ca.crt -CAkey ca.key \
  -CAcreateserial -out server.crt -days 365 -sha256

# Start rttys with mTLS (devices must present a cert signed by ca.crt)
./rttys \
  --sslcert server.crt \
  --sslkey  server.key \
  --cacert  ca.crt

# Without cacert = TLS-only (server auth, no client cert required)
./rttys --sslcert server.crt --sslkey server.key
```

--------------------------------

### Fetch Device Metadata with cURL

Source: https://context7.com/zhaojh329/rttys/llms.txt

Use this endpoint to retrieve metadata for a specific device. A 404 error is returned if the device is not connected.

```bash
curl -s -b cookies.txt "http://localhost:5913/dev/device001?group=factory"
# {
#   "id": "device001",
#   "description": "Raspberry Pi 4",
#   "connected": 120,
#   "uptime": 86400,
#   "proto": 5,
#   "ipaddr": "10.0.0.5"
# }

# 404 if device is not connected
curl -s -o /dev/null -w "%{http_code}" -b cookies.txt \
  "http://localhost:5913/dev/nonexistent"
# 404
```

--------------------------------

### Commit and Push Changes

Source: https://github.com/zhaojh329/rttys/blob/master/CONTRIBUTING.md

Commit your changes with a signoff and push them to your origin branch. Ensure your branch name matches the one you created.

```bash
git commit --signoff
git push origin rttys-1-fix
```

--------------------------------

### Performance Profiling (pprof)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Enable and access the Go pprof HTTP endpoint for live performance profiling of the RTTYS application.

```APIDOC
## Performance Profiling (pprof)

Enable the Go pprof HTTP endpoint for live profiling.

### Starting RTTYS with pprof enabled
Use the `--pprof` flag to specify the address and port for the pprof endpoint.

```bash
./rttys --pprof localhost:6060
```

### Accessing Profiles
- **CPU Profile**: Get a CPU profile for a specified duration (e.g., 30 seconds).
  ```bash
  go tool pprof http://localhost:6060/debug/pprof/profile?seconds=30
  ```
- **Heap Snapshot**: Retrieve a heap profile.
  ```bash
  go tool pprof http://localhost:6060/debug/pprof/heap
  ```
- **Goroutine Dump**: Get a detailed dump of all goroutines.
  ```bash
  curl http://localhost:6060/debug/pprof/goroutine?debug=1
  ```
- **List All Endpoints**: View all available pprof endpoints.
  ```bash
  curl http://localhost:6060/debug/pprof/
  ```
```

--------------------------------

### Device Registration Webhook (Python Flask)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Implement a Flask application to handle device registration requests. Return HTTP 200 to allow registration; otherwise, return a non-200 status code.

```python
from flask import Flask, request, jsonify

app = Flask(__name__)

ALLOWED_DEVICES = {"device001", "device002", "sensor-rpi"}

@app.route("/rttys-dev-hook", methods=["POST"])
def dev_hook():
    data = request.get_json()
    # data = {"group": "factory", "devid": "device001", "token": "abc123"}
    devid = data.get("devid", "")
    group = data.get("group", "")
    token = data.get("token", "")

    if devid not in ALLOWED_DEVICES:
        return jsonify({"error": "unknown device"}), 403

    print(f"Device {devid} (group={group}) connected with token={token}")
    return "", 200  # Allow registration

if __name__ == "__main__":
    app.run(port=8080)
```

--------------------------------

### Execute Command on Device

Source: https://context7.com/zhaojh329/rttys/llms.txt

Executes a command on a specified device and returns its output. Supports a timeout and fire-and-forget execution.

```APIDOC
## POST /cmd/:devid?group=<group>&wait=<seconds>

### Description
Execute a command on a device and return its output. The `wait` query parameter sets timeout in seconds (default: 30, max: 30, `0` = fire-and-forget).

### Method
POST

### Endpoint
/cmd/:devid

#### Query Parameters
- **group** (string) - Optional - Device group name
- **wait** (integer) - Optional - Timeout in seconds for command execution (default: 30, max: 30, 0 for fire-and-forget)

#### Request Body
- **username** (string) - Required - The username to execute the command as
- **cmd** (string) - Required - The command to execute
- **params** (array) - Optional - An array of parameters for the command

### Request Example
```bash
# Run 'uptime' as root, wait up to 10 seconds
curl -s -b cookies.txt -X POST \
  "http://localhost:5913/cmd/device001?wait=10" \
  -H "Content-Type: application/json" \
  -d '{
    "username": "root",
    "cmd": "uptime",
    "params": []
  }'
```

### Response
#### Success Response (200)
- **devid** (string) - The device ID
- **code** (integer) - The exit code of the command
- **stdout** (string) - Standard output of the command
- **stderr** (string) - Standard error of the command

#### Error Responses (HTTP 200 with error code in body)
- `{"err":1001,"msg":"invalid format"}` - Missing command or username.
- `{"err":1002,"msg":"device offline"}` - Device is not connected.
- `{"err":1003,"msg":"timeout"}` - Command execution exceeded the timeout.

### Response Example
```json
{
  "devid": "device001",
  "code": 0,
  "stdout": " 10:22:14 up 1 day,  0:04,  load average: 0.01, 0.05, 0.01",
  "stderr": ""
}
```
```

--------------------------------

### Run Rttys Docker Container with Configuration File

Source: https://context7.com/zhaojh329/rttys/llms.txt

Deploys the Rttys server in a Docker container, mounting a configuration file for persistent settings. Ports 5912 and 5913 are exposed for device and user access.

```bash
docker run -d \
  --name rttys \
  -p 5912:5912 \
  -p 5913:5913 \
  -v /etc/rttys/rttys.conf:/etc/rttys/rttys.conf:ro \
  rttys:latest -c /etc/rttys/rttys.conf
```

--------------------------------

### POST /signin

Source: https://context7.com/zhaojh329/rttys/llms.txt

Authenticates a user and returns a session cookie (`sid`). This endpoint is required if a password is set for the server.

```APIDOC
## POST /signin

### Description
Authenticate and receive a session cookie (`sid`). Required if `--password` is set.

### Method
POST

### Endpoint
`http://localhost:5913/signin`

### Request Body
- **password** (string) - Required - The password for authentication.

### Request Example
```json
{
  "password": "rttys"
}
```

### Response
#### Success Response (200)
- **sid** (string) - The session cookie.

#### Response Example
```
HTTP 200 on success; sets cookie: sid=<32-char hex>
```

#### Error Response (401)
- **Unauthorized**

#### Error Example
```
401
```
```

--------------------------------

### Build Rttys Docker Image

Source: https://context7.com/zhaojh329/rttys/llms.txt

Builds the Docker image for the Rttys server. This command assumes the Dockerfile is in the current directory.

```bash
docker build -t rttys:latest .
```

--------------------------------

### Run Rttys Docker Container with CLI Flags

Source: https://context7.com/zhaojh329/rttys/llms.txt

Deploys the Rttys server in a Docker container using command-line flags for configuration. This is suitable for simpler deployments or testing.

```bash
docker run -d \
  --name rttys \
  -p 5912:5912 \
  -p 5913:5913 \
  rttys:latest --token mytoken --password secret
```

--------------------------------

### HTTP Proxy to Device Services

Source: https://context7.com/zhaojh329/rttys/llms.txt

Establishes a proxied HTTP/HTTPS connection to a TCP service running on a device. This redirects the browser and uses a session cookie for routing.

```APIDOC
## GET /web/:devid/:proto/:addr/*path
## GET /web2/:group/:devid/:proto/:addr/*path

### Description
Establish a proxied HTTP/HTTPS connection to a TCP service on the device. This redirects the browser with a session cookie (`rtty-http-sid`) that the separate HTTP proxy listener uses to route traffic through the device.

### Method
GET

### Endpoint
/web/:devid/:proto/:addr/*path
/web2/:group/:devid/:proto/:addr/*path

#### Path Parameters
- **devid** (string) - Required - The device ID
- **group** (string) - Required (for /web2) - The device group name
- **proto** (string) - Required - The protocol (e.g., http, https)
- **addr** (string) - Required - The device's IP address and port (e.g., 192.168.1.1:80)
- **path** (string) - Optional - The path on the target service

### Request Example
```bash
# Access a web service running on device001 at 192.168.1.1:80
# Browser navigates to:
# http://localhost:5913/web/device001/http/192.168.1.1:80/

# Access an HTTPS service on port 443
# http://localhost:5913/web/device001/https/192.168.1.1:443/

# With group (web2 variant)
# http://localhost:5913/web2/factory/device001/http/10.0.0.1:8080/dashboard

# curl example (follows redirect, uses cookie jar)
curl -s -b cookies.txt -c cookies.txt -L \
  "http://localhost:5913/web/device001/http/192.168.1.1/index.html"
```

### Response
The server sets a `rtty-http-sid` cookie, redirects to the HTTP proxy port, and all subsequent requests are tunneled to the device automatically for 15 minutes of inactivity timeout.
```

--------------------------------

### Device Hook Integration

Source: https://context7.com/zhaojh329/rttys/llms.txt

Configure a webhook to be called when a device registers with RTTYS. The system expects an HTTP 200 response to allow registration, and any other status code to reject it.

```APIDOC
## Device Hook (`dev-hook-url`) — `POST`

### Description
Called when a device registers. Return HTTP 200 to allow, any other code to reject.

### Method
POST

### Endpoint
`/rttys-dev-hook`

### Request Body
- **group** (string) - Optional - The group the device belongs to.
- **devid** (string) - Required - The unique identifier of the device.
- **token** (string) - Optional - The token associated with the device.

### Response
#### Success Response (200)
Returns an empty body to allow registration.

#### Error Response (403)
Returns a JSON object with an error message if the device is not allowed.
```

--------------------------------

### Execute Remote Command with cURL

Source: https://context7.com/zhaojh329/rttys/llms.txt

Execute a command on a device and receive its output. The `wait` parameter controls the timeout. Error responses are returned in the JSON body with an HTTP 200 status.

```bash
# Run 'uptime' as root, wait up to 10 seconds
curl -s -b cookies.txt -X POST \
  "http://localhost:5913/cmd/device001?wait=10" \
  -H "Content-Type: application/json" \
  -d '{
    "username": "root",
    "cmd": "uptime",
    "params": []
  }'
# Success response:
# {
#   "devid": "device001",
#   "code": 0,
#   "stdout": " 10:22:14 up 1 day,  0:04,  load average: 0.01, 0.05, 0.01",
#   "stderr": ""
# }

# Run command with parameters
curl -s -b cookies.txt -X POST \
  "http://localhost:5913/cmd/device001?group=factory" \
  -H "Content-Type: application/json" \
  -d '{
    "username": "root",
    "cmd": "ls",
    "params": ["-la", "/tmp"]
  }'

# Error responses (all return HTTP 200 with error code in body):
# {"err":1001,"msg":"invalid format"}   -- missing cmd or username
# {"err":1002,"msg":"device offline"}   -- device not connected
# {"err":1003,"msg":"timeout"}          -- command took too long

# Fire-and-forget (wait=0): returns HTTP 200 immediately, no output
curl -s -o /dev/null -w "%{http_code}" -b cookies.txt -X POST \
  "http://localhost:5913/cmd/device001?wait=0" \
  -H "Content-Type: application/json" \
  -d '{"username":"root","cmd":"reboot","params":[]}'
# 200
```

--------------------------------

### User Access Webhook (Python Flask)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Create a Flask endpoint to validate user access requests. Rttys forwards original headers plus X-Rttys-Hook, X-Original-Method, and X-Original-URL. Return HTTP 200 to allow access.

```python
@app.route("/rttys-user-hook", methods=["GET"])
def user_hook():
    # Extra headers added by rttys:
    is_hook   = request.headers.get("X-Rttys-Hook")        # "true"
    method    = request.headers.get("X-Original-Method")   # "GET" / "POST"
    orig_url  = request.headers.get("X-Original-URL")      # "/connect/device001"

    # Original auth headers are forwarded too
    auth_token = request.headers.get("Authorization", "")

    if not is_valid_token(auth_token):
        return "", 403  # Block access

    print(f"User hook: method={method}, url={orig_url}")
    return "", 200  # Allow access

def is_valid_token(token):
    return token == "Bearer myapitoken"
```

--------------------------------

### Authenticate with Rttys API (POST /signin)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Authenticates a user with the Rttys API by sending a JSON payload containing the password. A successful request returns an HTTP 200 status and sets a session cookie (`sid`).

```bash
# Sign in
curl -s -c cookies.txt -X POST http://localhost:5913/signin \
  -H "Content-Type: application/json" \
  -d '{"password":"rttys"}'
# HTTP 200 on success; sets cookie: sid=<32-char hex>
```

```bash
# 401 Unauthorized on wrong password
curl -s -o /dev/null -w "%{http_code}" -X POST http://localhost:5913/signin \
  -H "Content-Type: application/json" \
  -d '{"password":"wrong"}'
# 401
```

--------------------------------

### Clone rttys Repository

Source: https://github.com/zhaojh329/rttys/blob/master/CONTRIBUTING.md

Clone the rttys repository from your GitHub account after forking it. Replace 'your_github_username' with your actual GitHub username.

```bash
git clone https://github.com/your_github_username/rttys.git
```

--------------------------------

### Open WebSocket Terminal Session

Source: https://context7.com/zhaojh329/rttys/llms.txt

Establishes a WebSocket connection for a terminal session to a device. Can also redirect to a UI or proxy the WebSocket connection.

```APIDOC
## GET /connect/:devid (WebSocket upgrade)

### Description
Open a WebSocket terminal session to a device. The browser navigates to this URL; if the request is a plain GET it redirects to the Vue UI route `/rtty/:devid`. If the `Upgrade: websocket` header is present, the connection is proxied directly to the device.

### Method
GET

### Endpoint
/connect/:devid

#### Query Parameters
- **group** (string) - Optional - Device group name

### Request Example
```javascript
// Browser WebSocket client example
const ws = new WebSocket(`ws://localhost:5913/connect/device001`);
// With group:
// const ws = new WebSocket(`ws://localhost:5913/connect/device001?group=factory`);

ws.onopen = () => console.log('WebSocket opened');

ws.onmessage = (event) => {
  if (typeof event.data === 'string') {
    const msg = JSON.parse(event.data);
    if (msg.type === 'login') {
      console.log('Terminal session established');
      // Resize terminal
      ws.send(JSON.stringify({ type: 'winsize', cols: 220, rows: 50 }));
    }
  } else {
    // Binary: first byte is padding; rest is terminal output
    const termData = event.data.slice(1);
    term.write(termData);  // xterm.js write
  }
};

// Send keystrokes as binary (first byte = 0 for term data, 1 for file)
ws.send(new Uint8Array([0, ...new TextEncoder().encode('ls -la\n')]));

// Send terminal resize
ws.send(JSON.stringify({ type: 'winsize', cols: 220, rows: 50 }));

// Flow-control ack
ws.send(JSON.stringify({ type: 'ack', ack: 1024 }));
```

### WebSocket Close Codes

| Code | Meaning |
|---|---|
| 4000 | Device offline |
| 4001 | Device busy (another session active) |
| 4002 | Login timeout (5 s) |
```

--------------------------------

### TLS / mTLS for Device Connections

Source: https://context7.com/zhaojh329/rttys/llms.txt

Secure device connections using TLS. For mutual TLS (mTLS), provide a CA certificate to verify client certificates.

```APIDOC
## TLS / mTLS for Device Connections

Secure the device listener with TLS; add `--cacert` to require client certificates (mTLS).

### Starting RTTYS with TLS
Use the `--sslcert` and `--sslkey` flags to specify the server certificate and private key.

```bash
./rttys --sslcert server.crt --sslkey server.key
```

### Starting RTTYS with mTLS
In addition to server certificate and key, use the `--cacert` flag to specify the Certificate Authority certificate. This requires devices to present a certificate signed by the provided CA.

```bash
./rttys \
  --sslcert server.crt \
  --sslkey  server.key \
  --cacert  ca.crt
```
```

--------------------------------

### Establish WebSocket Terminal Session

Source: https://context7.com/zhaojh329/rttys/llms.txt

Open a WebSocket connection for a terminal session to a device. The `Upgrade: websocket` header is required for direct proxying. Browser clients can use the `WebSocket` API.

```javascript
// Browser WebSocket client example
const ws = new WebSocket(`ws://localhost:5913/connect/device001`);
// With group:
// const ws = new WebSocket(`ws://localhost:5913/connect/device001?group=factory`);

ws.onopen = () => console.log('WebSocket opened');

ws.onmessage = (event) => {
  if (typeof event.data === 'string') {
    const msg = JSON.parse(event.data);
    if (msg.type === 'login') {
      console.log('Terminal session established');
      // Resize terminal
      ws.send(JSON.stringify({ type: 'winsize', cols: 220, rows: 50 }));
    }
  } else {
    // Binary: first byte is padding; rest is terminal output
    const termData = event.data.slice(1);
    term.write(termData);  // xterm.js write
  }
};

// Send keystrokes as binary (first byte = 0 for term data, 1 for file)
ws.send(new Uint8Array([0, ...new TextEncoder().encode('ls -la\n')]));

// Send terminal resize
ws.send(JSON.stringify({ type: 'winsize', cols: 220, rows: 50 }));

// Flow-control ack
ws.send(JSON.stringify({ type: 'ack', ack: 1024 }));
```

--------------------------------

### Fetch Device Metadata

Source: https://context7.com/zhaojh329/rttys/llms.txt

Retrieves metadata for a specific device. Supports filtering by group.

```APIDOC
## GET /dev/:devid?group=<group>

### Description
Fetch metadata for a single device.

### Method
GET

### Endpoint
/dev/:devid

#### Query Parameters
- **group** (string) - Optional - Device group name

### Response
#### Success Response (200)
- **id** (string) - Device unique ID
- **description** (string) - Human-readable device description
- **connected** (uint32) - Seconds since device connected to rttys
- **uptime** (uint32) - Device uptime in seconds (from heartbeat)
- **proto** (uint8) - RTTY protocol version
- **ipaddr** (string) - Device's TCP remote IP address

### Request Example
```bash
curl -s -b cookies.txt "http://localhost:5913/dev/device001?group=factory"
```

### Response Example
```json
{
  "id": "device001",
  "description": "Raspberry Pi 4",
  "connected": 120,
  "uptime": 86400,
  "proto": 5,
  "ipaddr": "10.0.0.5"
}
```
```

--------------------------------

### Proxy HTTP/HTTPS to Device Services with cURL

Source: https://context7.com/zhaojh329/rttys/llms.txt

Establish a proxied HTTP/HTTPS connection to a TCP service on the device. This redirects the browser with a session cookie. The `web2` variant includes the group name.

```bash
# Access a web service running on device001 at 192.168.1.1:80
# Browser navigates to:
# http://localhost:5913/web/device001/http/192.168.1.1:80/

# Access an HTTPS service on port 443
# http://localhost:5913/web/device001/https/192.168.1.1:443/

# With group (web2 variant)
# http://localhost:5913/web2/factory/device001/http/10.0.0.1:8080/dashboard

# curl example (follows redirect, uses cookie jar)
curl -s -b cookies.txt -c cookies.txt -L \
  "http://localhost:5913/web/device001/http/192.168.1.1/index.html"
```

--------------------------------

### File Transfer via WebSocket (JavaScript)

Source: https://context7.com/zhaojh329/rttys/llms.txt

Manage file uploads and downloads over a WebSocket connection. The first byte of binary messages indicates the channel (0 for terminal, 1 for file).

```javascript
// Upload a file to the device
async function uploadFile(ws, file) {
  // Step 1: Send file metadata
  ws.send(JSON.stringify({
    type: 'fileInfo',
    size: file.size,
    name: file.name
  }));

  // Step 2: Wait for device ready signal {"type":"recvfile"}
  // (handled in ws.onmessage)

  // Step 3: Send file data in chunks (first byte = 1 for file channel)
  const CHUNK = 4096;
  const reader = file.stream().getReader();
  while (true) {
    const { done, value } = await reader.read();
    if (done) break;
    const buf = new Uint8Array(1 + value.length);
    buf[0] = 1; // file channel
    buf.set(value, 1);
    ws.send(buf);
  }
}

// Handle incoming file messages
ws.onmessage = (event) => {
  if (typeof event.data === 'string') {
    const msg = JSON.parse(event.data);
    switch (msg.type) {
      case 'sendfile':
        // Device is pushing a file named msg.name — prepare to receive
        console.log(`Receiving file: ${msg.name}`);
        break;
      case 'recvfile':
        // Device is ready to receive — start sending chunks
        break;
      case 'fileAck':
        console.log('File transfer acknowledged by device');
        break;
    }
  } else {
    const data = new Uint8Array(await event.data.arrayBuffer());
    if (data[0] === 1) {
      // File data chunk: data.slice(1)
      fileChunks.push(data.slice(1));
    } else {
      term.write(data.slice(1)); // terminal output
    }
  }
};

// Cancel an in-progress file transfer
ws.send(JSON.stringify({ type: 'fileCanceled' }));

// Acknowledge receipt of a file chunk
ws.send(JSON.stringify({ type: 'fileAck' }));
```

--------------------------------

### File Transfer via WebSocket

Source: https://context7.com/zhaojh329/rttys/llms.txt

Manage file transfers over the same WebSocket connection used for terminal sessions. This involves sending file metadata, data chunks, and acknowledgments.

```APIDOC
## File Transfer via WebSocket

File transfers share the same `/connect/:devid` WebSocket. The first byte of every binary message indicates the channel (`0` = terminal, `1` = file).

### Sending a File
1. Send file metadata using `JSON.stringify({ type: 'fileInfo', size: file.size, name: file.name })`.
2. Wait for a `{"type":"recvfile"}` signal from the device.
3. Send file data in chunks, prefixing each chunk with a byte `1` to indicate the file channel.

### Receiving a File
- When the device initiates a file transfer, it sends `JSON.stringify({ type: 'sendfile', name: msg.name })`.
- The client should respond with `JSON.stringify({ type: 'recvfile' })` to signal readiness.
- File data chunks are received as binary messages, with the first byte indicating the channel (`1` for file).

### File Transfer Control
- **Cancel Transfer**: Send `JSON.stringify({ type: 'fileCanceled' })`.
- **Acknowledge Chunk**: Send `JSON.stringify({ type: 'fileAck' })`.
```

--------------------------------

### Handle RTTY HTTP Proxy Errors

Source: https://github.com/zhaojh329/rttys/blob/master/assets/http-proxy-err.html

This JavaScript code dynamically updates the error message and page title based on the error type (offline or unauthorized) and the user's language. It uses a translation map for multi-language support. Initialize this script on page load.

```javascript
const translations = { en: { 'Device Unavailable': 'Device Unavailable', 'Unauthorized Access': 'Unauthorized Access', 'Device offline message': 'The device is currently offline. Please check the device status and try again.', 'Unauthorized request message': 'You are not authorized to access this resource. Please check your session and try again.' }, 'zh-CN': { 'Device Unavailable': '设备不可用', 'Unauthorized Access': '未授权访问', 'Device offline message': '设备当前离线，请检查设备状态后重试。', 'Unauthorized request message': '您无权访问此资源。请检查您的会话并重试。' } }; function t(key, lang) { return translations[lang][key] || translations.en[key] || key; } function updateContent() { const errorType = '{{.}}'; const lang = navigator.language === 'zh-CN' ? 'zh-CN' : 'en'; let title = '', message = ''; switch (errorType) { case 'offline': title = t('Device Unavailable', lang); message = t('Device offline message', lang); break; case 'unauthorized': title = t('Unauthorized Access', lang); message = t('Unauthorized request message', lang); break; } document.getElementById('errorTitle').textContent = title; document.getElementById('errorMessage').textContent = message; // Update page title if (title) { document.title = title + ' - RTTY'; } else { document.title = 'Error - RTTY'; } } // Initialize page on load document.addEventListener('DOMContentLoaded', updateContent);
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.