# -*- test-case-name: twisted.trial._dist.test.test_workertrial -*-
#
# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.

"""
Implementation of C{AMP} worker commands, and main executable entry point for
the workers.

@since: 12.3
"""

import sys
import os
import errno


def _setupPath(environ):
"""
Override C{sys.path} with what the parent passed in B{TRIAL_PYTHONPATH}.

@see: twisted.trial._dist.disttrial.DistTrialRunner.launchWorkerProcesses
"""
if 'TRIAL_PYTHONPATH' in environ:
sys.path[:] = environ['TRIAL_PYTHONPATH'].split(os.pathsep)


_setupPath(os.environ)


from twisted.internet.protocol import FileWrapper
from twisted.python.log import startLoggingWithObserver, textFromEventDict
from twisted.trial._dist.options import WorkerOptions
from twisted.trial._dist import _WORKER_AMP_STDIN, _WORKER_AMP_STDOUT



class WorkerLogObserver(object):
"""
A log observer that forward its output to a C{AMP} protocol.
"""

def __init__(self, protocol):
"""
@param protocol: a connected C{AMP} protocol instance.
@type protocol: C{AMP}
"""
self.protocol = protocol


def emit(self, eventDict):
"""
Produce a log output.
"""
from twisted.trial._dist import managercommands
text = textFromEventDict(eventDict)
if text is None:
return
self.protocol.callRemote(managercommands.TestWrite, out=text)



def main(_fdopen=os.fdopen):
"""
Main function to be run if __name__ == "__main__".

@param _fdopen: If specified, the function to use in place of C{os.fdopen}.
@param _fdopen: C{callable}
"""
config = WorkerOptions()
config.parseOptions()

from twisted.trial._dist.worker import WorkerProtocol
workerProtocol = WorkerProtocol(config['force-gc'])

protocolIn = _fdopen(_WORKER_AMP_STDIN)
protocolOut = _fdopen(_WORKER_AMP_STDOUT, 'w')
workerProtocol.makeConnection(FileWrapper(protocolOut))

observer = WorkerLogObserver(workerProtocol)
startLoggingWithObserver(observer.emit, False)

while True:
try:
r = protocolIn.read(1)
except IOError, e:
if e.args[0] == errno.EINTR:
sys.exc_clear()
continue
else:
raise
if r == '':
break
else:
workerProtocol.dataReceived(r)
protocolOut.flush()
sys.stdout.flush()
sys.stderr.flush()

if config.tracer:
sys.settrace(None)
results = config.tracer.results()
results.write_results(show_missing=True, summary=False,
coverdir=config.coverdir().path)



if __name__ == '__main__':
main()