def get_connection_file(app=None):
"""Return the path to the connection file of an app
Parameters
----------
app : IPKernelApp instance [optional]
If unspecified, the currently running app will be used
"""
from traitlets.utils import filefind
if app is None:
from ipykernel.kernelapp import IPKernelApp
if not IPKernelApp.initialized():
raise RuntimeError("app not specified, and not in a running Kernel")
app = IPKernelApp.instance()
return filefind(app.connection_file, ['.', app.connection_dir])
def init_connection_file(self):
if not self.connection_file:
self.connection_file = "kernel-%s.json"%os.getpid()
try:
self.connection_file = filefind(self.connection_file, ['.', self.connection_dir])
except IOError:
self.log.debug("Connection file not found: %s", self.connection_file)
# This means I own it, and I'll create it in this directory:
os.makedirs(os.path.dirname(self.abs_connection_file), mode=0o700, exist_ok=True)
# Also, I will clean it up:
atexit.register(self.cleanup_connection_file)
return
try:
self.load_connection_file()
except Exception:
self.log.error("Failed to load connection file: %r", self.connection_file, exc_info=True)
self.exit(1)