I need to install on one of my Windows PC's some software that will periodically send a short HTTP POST request to my remote development server. The request is always the same and should get sent every minute.
What would you recommend as the best approach for that?
The things I considered are:
1. Creating a Windows service
2. Using a script in python (I have cygwin installed)
3. Scheduled task using a batch file (although I don't want the black cmd window to pop up in my face every minute)
Thanks for any additional ideas or hints on how to best implement it.
import urllib
import time
while True:
urllib.urlopen(url, post_data)
time.sleep(60)
If you have cygwin, you probably have cron - run a python script from your crontab.
This is trivially easy with a scheduled task which is the native Windows way to schedule tasks! There's no need for cygwin or Python or anything like that.
I have such a task running on my machine which pokes my Wordpress blog every few hours. The script is just a .bat file which calls wget. The task is configured to "Run whether user is logged on or not" which ensures that it runs when I'm not logged on. There's no "black cmd window".
You didn't say which version of Windows you are on and if you are on XP (unlucky for you if you are) then the configuration is probably different since the scheduled task interface changed quite a bit when Vista came out.
Related
I have a python script that checks the temperature every 24 hours, is there a way to leave it running if I shut the computer down/log off.
Shutdown - no.
Logoff - potentially, yes.
If you want to the script to automatically start when you turn the computer back on, then you can add the script to your startup folder (Windows) or schedule the script (Windows tasks, cron job, systemd timer).
If you really want a temperature tracker that is permanently available, you can use a low-power solution like the Raspberry Pi rather than leaving your pc on.
The best way to accomplish this is to have your program run on some type of server that your computer can connect to. A server could be anything from a raspberry pi to an old disused computer or a web server or cloud server. You would have to build a program that can be accessed from your computer, and depending on the server and you would access it in a lot of different ways depending the way you build your program and your server.
Doing things this way means your script will always be able to check the temperature because it will be running on a system that stays on.
Scripts are unable to run while your computer is powered off. What operating system are you running? How are you collecting the temperature? It is hard to give much more help without this information.
One thing I might suggest is powering on the system remotely at a scheduled time, using another networked machine.
You can take a look at the following pages
http://www.wikihow.com/Automatically-Turn-on-a-Computer-at-a-Specified-Time
http://lifehacker.com/5831504/how-can-i-start-and-shut-down-my-computer-automatically-every-morning
Additionally once it turn on, you can perform a cronjob, for execute your python code by a console command >> python yourfile.py . What is the Windows version of cron?
I have a simple python script to send data from a Windows 7 box to a remote computer via SFTP. The script is set to continuously send a single file every 5 minutes. This all works fine but I'm worried about the off chance that the process stops or fails and the customer doesn't notice the data files have stopped coming in. I've found several ways to monitor python processes in a ubuntu/unix environment but nothing for Windows.
If there are no other mitigating factors in your design or requirements, my suggestion would be to simplify the script so that it doesn't do the polling; it simply sends the file when invoked, and use Windows Scheduler to invoke the script on whatever schedule you need. By relying on a core Windows service, you can factor that complexity out of your script.
You can check out restartme the following link shows how you can use it
http://www.howtogeek.com/130665/quickly-and-automatically-restart-a-windows-program-when-it-crashes/
I am writing a test application in python and to test some particular scenario, I need to launch my python child process in windows SYSTEM account.
I can do this by creating exe from my python script and then use that while creating windows service. But this option is not good for me because in future if I change anything in my python script then I have to regenerate exe every-time.
If anybody have any better idea about how to do this then please let me know.
Bishnu
Create a service that runs permanently.
Arrange for the service to have an IPC communications channel.
From your desktop python code, send messages to the service down that IPC channel. These messages specify the action to be taken by the service.
The service receives the message and performs the action. That is, executes the python code that the sender requests.
This allows you to decouple the service from the python code that it executes and so allows you to avoid repeatedly re-installing a service.
If you don't want to run in a service then you can use CreateProcessAsUser or similar APIs.
You could also use Windows Task Scheduler, it can run a script under SYSTEM account and its interface is easy (if you do not test too often :-) )
To run a file with system account privileges, you can use psexec. Download this :
Sysinternals
Then you may use :
os.system
or
subprocess.call
And execute:
PSEXEC -i -s -d CMD "path\to\yourfile"
Just came across this one - I know, a bit late, but anyway. I encountered a similar situation and I solved it with NSSM (Non_Sucking Service Manager). Basically, this program enables you to start any executable as a service, which I did with my Python executable and gave it the Python script I was testing on as a parameter.
So I could run the service and edit the script however I wanted. I just had to restart the service when I made any changes to the script.
One point for productive environments: Try not to rely on third party software like NSSM. You could also achieve this with the standard SC command (see this answer) or PowerShell (see this MS doc).
I have set up a python script to run daily from my pc by adding it to the start up section in Windows 7.
However, does any know how I can set up a job (probably from Task Scheduler) to alert me if the program has stopped running i.e. if for some reason the cmd screen is closed etc... so that I can restart it or automatically restart it
Mike
To me it sounds like what you actually are looking for is windows services.
About services
If you don't know what a windows service is, then msdn have some documentation about it.
Creating a windows service in python
For a concrete example on how to do this in python, go here
I am working with scrapy 0.20 on python 2.7
Question
What is the best python scheduler.
My need
I need to run my spider, which is a python script, each 3 hours.
What I have thought
I tried using windows scheduler features which comes with Windows 7 and It works good. I am able to run a python script each 3 hours but I may deploy my python script on Linux server so I may not be able to use this option.
I create a Java application using Quartz-Scheduler. It works good but this is a third library, which my manager may refuse.
I created a windows service and I made it fire the script each three hours. It works but I may deploy my python script on a Linux server so I may not be able to use this option.
I am asking about the best practice to fire a python script
I tried using windows scheduler features which comes with Windows 7 and it works good.
So that works fine for you already. Good, no need to change your script to do scheduling work yourself.
but I may deploy my python script on Linux server so I may not be able to use this option.
On Linux, you can use cron jobs to achieve this.
The other way would be to simply keep your script running the whole time, but pause it for the three hours in which you are doing nothing. So you don’t need to set up anything on the target machine, but just need to run the script in the background, and it will keep running and doing its job.
This is exactly how job schedulers work btw. They are launched early when the operating system starts, and then they just keep running forever and every short time interval (a minute or so) they check if there is any job on their list that needs to run now. And if that’s the case, they spawn a new process and run the job.
So if you wanted to make such a scheduler in Python, you would just keep it running forever, and once every time interval (in your case 3 hours because you only have a single job anyway), you start your job. That can be in a separate process, in a separate thread, or indirectly in a separate thread using asynchronous functions.
The best way to deploy/schedule your scrapy project is to use scrapyd server.
You should install scrapyd.
sudo-apt get install scrapyd
You change your project config file to something like this :
[deploy:somename]
url = http://localhost:6800/ ## this the default
project = scrapy_project
you deploy your project under the scrapyd server:
scrapy deploy somename
You change your poll interval in /etc/scrapyd/conf.d/default-000 to 3 hours ( default to 5 seconds):
poll_interval = 10800
You configure your spider something like :
curl http://localhost:6800/schedule.json -d project=scrapy_project -d spider=myspider
You can use the web service to monitor your jobs:
http://localhost:6800/
PS: I just test it under ubuntu So I am not sure that a windows version exist. If not you can install a VM with ubuntu to launch the spiders.
Well, there's always the charming
sched
(docs) module, which provides a generic scheduling interface.
Give it a time function and a sleep function, and it'll give you back a pretty nice and extensible scheduler.
It's not system-level, but if you can run it as a service, it should suffice.