start_app.py

# -*- coding: utf-8 -*-

# Std imports
import atexit
import os
import os.path as osp
import random
import socket
import time

# Local imports
from spyderlib.cli_options import get_options
from spyderlib.baseconfig import get_conf_path, running_in_mac_app
from spyderlib.config import CONF
from spyderlib.baseconfig import DEV, TEST
from spyderlib.utils.external import lockfile
from spyderlib.py3compat import is_unicode


def send_args_to_spyder(args):
    """Simple socket client used to send the args passed to the Spyder 
    executable to an already running instance.
    
    Args can be Python scripts or files with these extensions: .spydata, .mat,
    .npy, or .h5, which can be imported by the Variable Explorer."""
    port = CONF.get('main', 'open_files_port')
    
    # Wait ~50 secs for the server to be up
    # Taken from http://stackoverflow.com/a/4766598/438386
    for _x in range(200):
        try:
            for arg in args:
                client = socket.socket(socket.AF_INET, socket.SOCK_STREAM,
                                       socket.IPPROTO_TCP)
                client.connect(("127.0.0.1", port))
                if is_unicode(arg):
                    arg = arg.encode('utf-8')
                client.send(osp.abspath(arg))
                client.close()
        except socket.error:
            time.sleep(0.25)
            continue
        break


def main():
    """Start Spyder application. If single instance mode is turned on (default
    behavior) and an instance of Spyder is already running, this will just 
    parse and send command line options to the application."""

    # Renaming old configuration files (the '.' prefix has been removed)
    # (except for .spyder.ini --> spyder.ini, which is done in userconfig.py)
    if DEV is None:
        cpath = get_conf_path()
        for fname in os.listdir(cpath):
            if fname.startswith('.'):
                old, new = osp.join(cpath, fname), osp.join(cpath, fname[1:])
                try:
                    os.rename(old, new)
                except OSError:
                    pass

    # Parse command line options
    options, args = get_options()

    if CONF.get('main', 'single_instance') and not options.new_instance \
      and not running_in_mac_app():
        # Minimal delay (0.1-0.2 secs) to avoid that several
        # instances started at the same time step in their
        # own foots while trying to create the lock file
        time.sleep(random.randrange(1000, 2000, 90)/10000.)
        
        # Lock file creation
        lockf = get_conf_path('spyder.lock')
        lock = lockfile.FilesystemLock(lockf)
        
        # lock.lock() tries to lock spyder.lock. If it fails,
        # it returns False and so we try to start the client
        if not lock.lock():
            if args:
                send_args_to_spyder(args)
        else:
            if TEST is None:
                atexit.register(lock.unlock)
            from spyderlib import spyder
            spyder.main()
    else:
        from spyderlib import spyder
        spyder.main()


if __name__ == "__main__":
    main()