Add Jupyter notebook server execution example

examples/execute_jupyter_notebook_server.py

@@ -0,0 +1,57 @@
+import os
+import sys
+import subprocess
+from copy import deepcopy
+import socket
+from tempfile import mkstemp
+import jupyter
+from trains import Task
+
+
+# initialize TRAINS
+task = Task.init(project_name='examples', task_name='Remote Jupyter NoteBook')
+
+# get rid of all the runtime TRAINS
+preserve = ('TRAINS_API_HOST', 'TRAINS_WEB_HOST', 'TRAINS_FILES_HOST', 'TRAINS_CONFIG_FILE',
+            'TRAINS_API_ACCESS_KEY', 'TRAINS_API_SECRET_KEY', 'TRAINS_API_HOST_VERIFY_CERT')
+
+# setup os environment
+env = deepcopy(os.environ)
+for key in os.environ:
+    if key.startswith('TRAINS') and key not in preserve:
+        env.pop(key, None)
+
+# execute jupyter notebook
+fd, local_filename = mkstemp()
+print('Running Jupyter Notebook Server on {} [{}]'.format(socket.gethostname(), socket.gethostbyname(socket.gethostname())))
+process = subprocess.Popen([sys.executable, '-m', 'jupyter', 'notebook'], env=env, stdout=fd, stderr=fd)
+
+# print stdout/stderr
+prev_line_count = 0
+while True:
+    try:
+        process.wait(timeout=2.0 if prev_line_count == 0 else 15.0)
+    except subprocess.TimeoutExpired:
+        with open(local_filename, "rt") as f:
+            # read new lines
+            new_lines = f.readlines()
+            if not new_lines:
+                continue
+            output = ''.join(new_lines)
+            print(output)
+            # update task comment with jupyter notebook server links
+            if prev_line_count == 0:
+                task.comment += '\n' + ''.join(line for line in new_lines if 'http://' in line or 'https://' in line)
+            prev_line_count += len(new_lines)
+
+        os.lseek(fd, 0, 0)
+        os.ftruncate(fd, 0)
+        continue
+    break
+
+# cleanup
+os.close(fd)
+try:
+    os.unlink(local_filename)
+except:
+    pass