Added warning.

Added warning for users who's processes are killed.

roles/kill_memory_hogs/files/kill_hoggs.py

@@ -6,6 +6,7 @@ import json
 import logging
 import psutil
 import requests
+import subprocess
 import time
 import yaml
 
@@ -32,6 +33,33 @@ def post_to_slack(message: str):
     logging.info(str(response.status_code) + str(response.text))
 
 
+def send_message_to_terminals(user: str, message: str):
+    """
+    Sends <message> to all terminals on which <user> is logged in.
+    """
+    terminals = find_terminals_of_user(user)
+    for terminal in terminals:
+        subprocess.run(
+            'echo "{message}" | write {user} {terminal}'.format(
+                message=message, user=user, terminal=terminal),
+            shell=True)
+
+
+def find_terminals_of_user(user: str):
+    """
+    Args:
+        user (str): The user who's terminals to return.
+    Returns:
+        list: A list of terminals (string)
+    """
+    terminals = subprocess.run('w -s -h', shell=True, capture_output=True)
+    return [
+        t.split()[1]
+        for t in str(terminals.stdout).strip('b\'').strip('').split('\\n')
+        if t != ''
+    ]
+
+
 def on_terminate(proc):
     """
     Callback for terminate()
@@ -60,7 +88,8 @@ def kill_hogs(memory_threshold,
               cpu_threshold,
               dummy: bool = False,
               slack: bool = False,
-              interval: float = .3):
+              interval: float = .3,
+              warning: str = ''):
     """
     Kill all processes of a user using more than <threshold> % of memory. And cpu.
     For efficiency reasons only processes using more than .1 % of the available
@@ -105,23 +134,27 @@ def kill_hogs(memory_threshold,
             users[username]['processes'].append(proc)
         except (psutil.NoSuchProcess, FileNotFoundError) as e:
             pass
-            #logging.exception(e)
 
     for username, data in users.items():
         if data['memory_percent'] > memory_threshold or data['cpu_percent'] > cpu_threshold:
             message = [
-                'User {} uses {:.2f} % of cpu. '.format(
-                    username, data['cpu_percent']),
-                'User {} uses {:.2f} % of memory. '.format(
-                    username, data['memory_percent']),
+                'User {} uses \n {:.2f} % of cpu. '.format(
+                    username,
+                    data['cpu_percent']), '{:.2f} % of memory. '.format(
+                        username, data['memory_percent']),
                 'The following processes will be killed:'
             ]
             for proc in data['processes']:
-                message.append('{} pid {} {} memory {:.2f}% cpu {:.2f}%'.format(
-                    proc.username(), proc.pid, proc.name(),
-                    proc.cached_memory_percent,
-                    proc.cached_cpu_percent))
+                message.append(
+                    '{} pid {} {} memory {:.2f}% cpu {:.2f}%'.format(
+                        proc.username(), proc.pid, proc.name(),
+                        proc.cached_memory_percent, proc.cached_cpu_percent))
             logging.info('\n'.join(message))
+            if warning == '':
+                warning = """Please submit your processes as a job.
+Your processes have been killed and this incident has been reported.
+For more information, see https://redmine.hpc.rug.nl/redmine/projects/peregrine/wiki/FAQ"""
+            send_message_to_terminals(proc.username(), warning)
             if slack:
                 post_to_slack('\n'.join(message))
             if not dummy: