[SPARK-8170] [PYTHON] Add signal handler to trap Ctrl-C in pyspark and cancel all running jobs

This patch adds a signal handler to trap Ctrl-C and cancels running job.

Author: Ashwin Shankar <ashankar@netflix.com>

Closes #9033 from ashwinshankar77/master.

python/pyspark/context.py

@@ -19,6 +19,7 @@ from __future__ import print_function
 
 import os
 import shutil
+import signal
 import sys
 from threading import Lock
 from tempfile import NamedTemporaryFile
@@ -217,6 +218,12 @@ class SparkContext(object):
         else:
             self.profiler_collector = None
 
+        # create a signal handler which would be invoked on receiving SIGINT
+        def signal_handler(signal, frame):
+            self.cancelAllJobs()
+
+        signal.signal(signal.SIGINT, signal_handler)
+
     def _initialize_context(self, jconf):
         """
         Initialize SparkContext in function to allow subclass specific initialization