I tried to create a pgAgent Job, but I can't seem to make it work the way I want. I can schedule a maintenance and put my script there, but it is not exactly what I want to do.
To be more precise, what I want to do is to start a script that will subscribe to a broker. I don't want the user to start the script manually. Is there something I can do?
It is a bit unclear what you want to do.
If you want some program to be started right after PostgreSQL, create an appropriate startup script (that depends on your operating system).
If you want something to run in the database right when it is starting up, write a PostgreSQL module in C and add it to shared_preload_libraries in postgresql.conf.
Related
I created a python script that work as a bot for instagram (using selenium).
Currently I have 5 profile running, for each of them I have all the files stored in folders (called with the name of the ig profile) and for each profile I have a screen where I can see the "log" of each program.
But now, 5 profile are difficult to manage and sometimes also a little messy.
Is there a way to see the log of all 5 scripts in a unique window?
I'm open also to another way to run the scripts in the background, maybe not "screen" but something else.
Thankyou
If you really want to go the clean way and if you think this will get bigger, you might want to have a look towards Django and Celery.
You can create a web interface, so that you can monitor any way you like.
And you can have cron jobs with Celery so that your bot is always on, or has recurring tasks, etc...
More info on their respective docs, as usual. http://docs.celeryproject.org/en/latest/userguide/periodic-tasks.html
in my vps i have run 4 Python Script and its been 60 days that i don't reboot my vps and now i have to, but if i reboot vps my python Variables & data will be removed because i don't store them in file and they are store in variables in python script.
my OS is Ubuntu Server 16.04 LTS and i was run my python codes with nohup command until they can run in background.
Now i need a way to stop my scripts without removing they variables and start them with same variables and data after i reboot my vps.
Is There Any Way That I Can Do This?
In Addition, I'm sorry for writing mistakes in my question.
Python doesn't provide any way of doing this.
But you might be able to use CRIU, or a similar tool, to freeze and snapshot the interpreter process. Then, after restart, you can resume the snapshot into a new process that just picks up exactly where you left off.
It may not work.1 But there's a good chance it will. This is essentially the same thing as a Live Migration in the CRIU docs, except that you're not migrating to a new computer/container/etc., just to the future of the same computer. So, start reading with that page, and follow the links from there.
You should probably test before you commit to it.
* Try it (obviously don't include the system restart, just kill -9 the executable) on a Python script that doesn't do anything important (maybe increments a counter, print it out, sleep for a second, repeat.
* Maybe try it on a script that does similar kinds of stuff to what yours are doing.
* If it's safe to have two copies of one of your programs running at the same time (they're not going to stomp all over each other writing to the same file, or fight over the same socket, or whatever), start a second copy and test dump/kill/resume that.
* Try it on one of your real processes, still without restart.
* Try it on all four.
* Cross your fingers, sacrifice a chicken, and do it for real.
If that doesn't pan out, the only option I can think of is to go through your scripts, manually figure out everything that needs to be saved and how it could be accessed from the top-level global, and do that in the debugger.
Ideally, you'll write a script that will automate accessing and saving all that stuff—plus another one to feed it into a new instance at restart. Then you just pdb the live interpreters and start dumping everything.
This is guaranteed to be a whole lot of work, and not much fun. On the plus side, it is guaranteed to work if you do it right. On the third hand, it's pretty easy to not do it right.
1. If you rely on open files, pipes, sockets, etc., CRIU does about as much as you could do, which is more than you might expect at first, but still not everything you could possibly want… Also, if you're using almost all of your RAM, it can be hard to wedge things back into exactly the same state. And there are probably other possible issues.
How can I access a running Python script's variable? Or access a function, to set the variable. I want to access it from the command line or from another Python script, that doesn't matter.
For example,
I have one script running run_motor.py, with a variable called mustRun. When the user pushes the stop button it should access the variable mustRun to change it to false.
If you want to interact with a running python script and modify some variables in it (I don't know why you want to do that, but... meh) you can have a look at Pyrasite.
Here is a demo of Pyrasite on asciinema
This is damn impressive.
By the way just so you know, that's NOT the best practice for what you want to do. I assume this is for testing purpose because using that kind of script in production or something like that wouldn't be safe at all...
Easiest way of accomplishing this is to run a small TCP server in a thread and have it change the variable you want to change when it receives a command to do so. Then write a python script that sends the stop command to that TCP server.
To work a bit on my Python, I decided to try to code a simple script for my private use which monitors sites with offers and sends you an email whenever a new offer which you are interested in pops out. I guess I could handle the coding part (extracting the newest one from HTML and such) but I've never really run online any script which requires being fired every N minutes or so. What kind of hosting/server do I need to make my script run independently of my computer and refresh every, say, 5 minutes sending me an email when there's an update?
If you have shell access, you an use crontab to schedule a recurring job.
Otherwise you can use a service like SetCronJob or EasyCron or similar to invoke a script regularly.
Some hosters also provide similar functionalities in their administration interface...
I'm running a python script manually that fetches data in JSON format.How do I automate this script to run automatically on an hourly basis?
I'm working on Windows7.Can I use tools like Task scheduler?If I can use it,what do I need to put in the batch file?
Can I use tools like Task scheduler?
Yes. Any tool that can run arbitrary programs can run your Python script. Pick the one you like best.
If I can use it,what do I need to put in the batch file?
What batch file? Task Scheduler takes anything that can be run, with arguments—a C program, a .NET program, even a document with a default app associated with it. So, there's no reason you need a batch file. Use C:\Python33\python.exe (or whatever the appropriate path is) as your executable, and your script's path (and its arguments, if any) as the arguments. Just as you do when running the script from the command line.
See Using the Task Scheduler in MSDN for some simple examples, and Task Scheduler Schema Elements or Task Scheduler Scripting Objects for reference (depending on whether you want to create the schedule in XML, or via the scripting interface).
You want to create an ExecAction with Path set to "C:\Python33\python.exe" and Arguments set to "C:\MyStuff\myscript.py", and a RepetitionPattern with Interval set to "PT1H". You should be able to figure out the rest from there.
As sr2222 points out in the comments, often you end up scheduling tasks frequently, and needing to programmatically control their scheduling. If you need this, you can control Task Scheduler's scripting interface from Python, or build something on top of Task Scheduler, or use a different tool that's a bit easier to get at from Python and has more helpful examples online, etc.—but when you get to that point, take a step back and look at whether you're over-using OS task scheduling. (If you start adding delays or tweaking times to make sure the daily foo1.py job never runs until 5 minutes after the most recent hourly foo0.py has finished its job, you're over-using OS task scheduling—but it's not always that obvious.)
May I suggest WinAutomation or AutoMate. These two do the exact same thing, except the UI is a little different. I prefer WinAutomation, because the scripts are a little easier to build.
Yes, you can use the Task Scheduler to run the script on an hourly bases.
To execute a python script via a Batch File, use the following code:
start path_to_python_exe path_to_python_file
Example:
start C:\Users\harshgoyal\AppData\Local\Continuum\Anaconda3\python.exe %UserProfile%\Documents\test_script.py
If python is set as Window’s Environment Window then you can reduce the syntax to:
start python %UserProfile%\Documents\test_script.py
What I generally do is run the batch file once via Task Scheduler and within the python script I call a thread/timer every hour.
class threading.Timer(interval, function, args=None, kwargs=None)