Connection Management

def write_connection_file(fname=None, shell_port=0, iopub_port=0, 
                         stdin_port=0, control_port=0, hb_port=0,
                         ip='127.0.0.1', key=b'', transport='tcp',
                         signature_scheme='hmac-sha256', kernel_name=''):
    """
    Write connection information to a JSON file.
    
    Re-exported from jupyter_client for convenience.
    
    Parameters:
    - fname (str, optional): Filename for connection file
    - shell_port (int): Port for shell channel
    - iopub_port (int): Port for IOPub channel  
    - stdin_port (int): Port for stdin channel
    - control_port (int): Port for control channel
    - hb_port (int): Port for heartbeat
    - ip (str): IP address for connections
    - key (bytes): HMAC key for message authentication
    - transport (str): Transport protocol ('tcp' or 'ipc')
    - signature_scheme (str): Message signature scheme
    - kernel_name (str): Name of the kernel
    
    Returns:
    str: Path to the written connection file
    """

def get_connection_file():
    """
    Get the path to the current kernel's connection file.
    
    Returns the connection file path for the currently running kernel,
    or None if not running in a kernel context.
    
    Returns:
    str or None: Path to connection file, or None if not in kernel
    """

def find_connection_file(filename_or_glob='kernel-*.json', profile=None):
    """
    Find a connection file by name or glob pattern.
    
    **DEPRECATED**: This function is deprecated and may be removed.
    
    Parameters:
    - filename_or_glob (str): Filename or glob pattern to search
    - profile (str, optional): IPython profile directory to search
    
    Returns:
    str: Path to found connection file
    
    Raises:
    IOError: If no matching connection file is found
    """

def get_connection_info():
    """
    Get connection information for the current kernel.
    
    Returns connection details including ports, IP address, and other
    network configuration needed to connect to the running kernel.
    
    Returns:
    dict: Connection information dictionary containing:
        - shell_port (int): Shell channel port
        - iopub_port (int): IOPub channel port
        - stdin_port (int): Stdin channel port
        - control_port (int): Control channel port
        - hb_port (int): Heartbeat port
        - ip (str): IP address
        - key (str): HMAC key (base64 encoded)
        - transport (str): Transport protocol
        - signature_scheme (str): Signature scheme
    
    Raises:
    RuntimeError: If not running in a kernel context
    """

def connect_qtconsole(argv=None, **kwargs):
    """
    Connect a qtconsole to the current kernel.
    
    Launches a new qtconsole instance connected to the currently
    running kernel using the kernel's connection information.
    
    Parameters:
    - argv (list, optional): Additional command-line arguments for qtconsole
    - **kwargs: Additional options passed to qtconsole
    
    Returns:
    subprocess.Popen: Process object for the launched qtconsole
    
    Raises:
    RuntimeError: If not running in a kernel context
    ImportError: If qtconsole is not available
    """

from ipykernel import get_connection_info, get_connection_file

# Get current kernel's connection info (only works in kernel context)
try:
    info = get_connection_info()
    print(f"Kernel IP: {info['ip']}")
    print(f"Shell port: {info['shell_port']}")
    print(f"IOPub port: {info['iopub_port']}")
    
    # Get connection file path
    conn_file = get_connection_file()
    print(f"Connection file: {conn_file}")
    
except RuntimeError:
    print("Not running in a kernel context")

from ipykernel import connect_qtconsole

# Connect qtconsole to current kernel (only works in kernel context)
try:
    process = connect_qtconsole()
    print(f"Started qtconsole with PID: {process.pid}")
    
except RuntimeError:
    print("Not running in a kernel context")
except ImportError:
    print("qtconsole not available")

from ipykernel import write_connection_file

# Create a connection file with specific configuration
conn_file = write_connection_file(
    fname='my-kernel.json',
    ip='192.168.1.100',
    shell_port=54321,
    iopub_port=54322,
    stdin_port=54323,
    control_port=54324,
    hb_port=54325,
    key=b'my-secret-key',
    kernel_name='my-python-kernel'
)

print(f"Created connection file: {conn_file}")

from ipykernel import find_connection_file

# Find connection files (deprecated function)
try:
    conn_file = find_connection_file('kernel-*.json')
    print(f"Found connection file: {conn_file}")
    
except IOError:
    print("No connection files found")

import json
from ipykernel import get_connection_file

# Read connection info from file
try:
    conn_file = get_connection_file()
    if conn_file:
        with open(conn_file, 'r') as f:
            conn_info = json.load(f)
        
        print("Connection configuration:")
        for key, value in conn_info.items():
            print(f"  {key}: {value}")
            
except (RuntimeError, FileNotFoundError):
    print("Could not read connection information")

ConnectionInfo = {
    "shell_port": int,      # Port for shell messages
    "iopub_port": int,      # Port for IOPub messages  
    "stdin_port": int,      # Port for stdin messages
    "control_port": int,    # Port for control messages
    "hb_port": int,         # Port for heartbeat
    "ip": str,              # IP address for connections
    "key": str,             # HMAC key (base64 encoded)
    "transport": str,       # Transport protocol ('tcp' or 'ipc')
    "signature_scheme": str, # Message signature scheme
    "kernel_name": str      # Kernel identifier
}