Can fabric run a local script on a remote machine? - python

I have myfile.py on my local machine.
I want to do something like:
from fabric.api import env, run
env.host_string = 'whatever.com'
def run_script():
run('python myfile.py')
but of course, this returns can't open file 'myfile.py': [Errno 2] No such file or directory How can I run this file remotely? Do I have to put it onto whatever.com?

You can first push your myfile.py to the remote machine using fabric.operations.put and then run the script like you've attempted to.
But make sure the path to your script is either an absolute path or relative to the current directory from which the remote commands are being executed, this can be found out using cwd you can also manually cd into the remote folder using fabric.context_managers.cd

Related

CWD in vsCode / sqlite3

I created a workspace in vsCode at path/to/workspace and started using sqlite3.connect("data.db"). My first database would be created correctly - but after doing so again in another folder path/to/workspace/subfolder ,
sqlite3.connect("data.db") would still connect to the db at path/to/workspace.
os.path.abspath(".") returns path/to/workspace in the scripts of both directories, so the cwd just remains the directory of the workspace.
(1) Why is the cwd of an executed script not the path to the script but rather the path to the workspace? / Why doesn't sqlite3 simply connect to databases relative to the path to the script that is executed?
I found that I can solve that with os:
path = os.path.dirname(__file__)
con = sqlite3.connect(path + "\data.db")
(2) Is that approach a safe way to handle that problem also considering the portability of a project?
Which cwd you get in the script depends on the cwd in the terminal, in other words, the routs in the terminal where you execute your script. For example:
If you want to change the route to the parent folder of the script you want to execute when you create a new terminal, you can add this in the settings.json file:
"terminal.integrated.cwd": "${fileDirname}",
But it does not work when you execute the command of Run Python File in Terminal, because the terminal was created by the Python extension, you can add this in the settings.json file to achieve it:
"python.terminal.executeInFileDir": true,
And you can add this in the launch.json file to modify the route in debugging mode:
"cwd": "${fileDirname}"
But both of the above methods were not recommended, Remain the cwd to the workspace can make the structure clearly.

Run Python Script From Script Directory/Current Directory

[Introduction]
Hi! I'm working on a python script to automate installation of UWP-Apps, it's been a long time i'm not touching Python; until this day. The script uses Depedencies inside the script directory, i've looking up on my older scripts and found this specific code.
os.chdir(os.path.dirname(sys.argv[0]))
[Problematic]
However, using the above code doesn't work on my current script but it's working fine on older scripts. When using above, it shows:
OSError: [WinError 123] The filename, directory name, or volume label syntax is incorrect: ''
Already looking up on Internet about this topic; but most of them was talking about running the script from outer/different directory that leads me to dead end.
Any helps is appreciated :)
The easiest answer is probably to change your working directory, then call the .py file from where it is:
cd path/to/python/file && python ../.py
Of course you might find it even easier to write a script that does it all for you, like so:
Save this as runPython.sh in the directory where you're running the python script from, is:
#!/bin/sh
cd path/to/python/file
python ../script.py
Make it executable (for yourself):
chmod +x ./runPython.sh
Then you can simply enter your directory and run it:
./runPython.sh
If you want to only make changes to the python script:
mydir = os.getcwd() # would be the folder where you're running the file
mydir_tmp = "path/to/python/file" # get the path
mydir_new = os.chdir(mydir_tmp) # change the current working directory
mydir = os.getcwd()
The reason you got an error was because sys.argv[0] is the name of the file itself, instead you can pass the directory as a string and use sys.argv[1] instead.
import os
from os.path import abspath, dirname
os.chdir(dirname(abspath(__file__)))
You can use dirname(abspath(__file__))) to get the parent directory of the python script and os.chdir into it to make the script run in the directory where it is located.

Fabric2 get file raises IsADirectoryError

I am trying to convert Fabric 1 to Fabric 2 script and I have the following statement to get the remote file:
c.get(os.path.join(working_dir, "dist/*.tar.gz"), "dist"))
It used to work just fine, copy a file from remote computer to a local directory called dist. However, with Fabric2 it fails with
"IsADirectoryError: [Errno 21] Is a directory: '/home/rapolas/projects/dist'"
Sure enough, it is a directory, but that is exactly what I want, to put that remote file (there is only one, but I don't have its name) into local directory. According to docs:
For example, if the local path is a directory, the remote path’s base filename will be added onto it (so get('foo/bar/file.txt', '/tmp/') would result in creation or overwriting of /tmp/file.txt).
but for some reason, it doesn't work. Am I doing something wrong?

Run python from bash script that is run by another bash script

I currently have a folder structure that will contain a few python scripts which need to be fired from a certain folder but I would like to write a global script that runs each python script via a seperate script in each folder.
-Obtainer
--Persona
---Arthur
----start.sh
--Initialise.sh
-Persona
--Arthur
---lib
----pybot
-----pybot.py
When I run initialise I am aiming to make initialise run "start.sh" Arthur is the bot and there will be more folders with different names and initialise with find and fire each start.sh.
In initialise.sh I have:
#!/bin/bash
. ./Persona/Arthur/start.sh
In start.sh I have:
#!/bin/bash
python ../../../Persona/Arthur/lib/pybot/pybot.py
I get this error:
python: can't open file '../../../Persona/Arthur/lib/pybot/pybot.py': [Errno 2] No such file or directory
However if I run the start.sh itself from its directory it runs fine. This is because I assume it's running it from the proper shell and consequently directory. Is there a way to make the main script run the start.sh in it's own shell like it is being run by itself? The reason why is because the pybot.py saves a bunch of files to where the start script is and because there will be more than one bot I need them to save in each seperate folder.
In the first place, do not source when you mean calling it,
#!/bin/bash
. ./Persona/Arthur/start.sh
Don't do this.
Your script has a number of issue. It won't work because of your current working directory is uncertain. You'd better have your script derive the path to relieve yourself from the hustle of abs paths or relative paths.
The general code could be
script_dir=`dirname "${BASH_SOURCE[0]}"`
then you can use this to derive the path of your target file,
#!/bin/bash
script_dir=`dirname "${BASH_SOURCE[0]}"`
"$script_dir/Persona/Arthur/start.sh"
Your python invocation becomes:
#!/bin/bash
script_dir=`dirname "${BASH_SOURCE[0]}"`
python "$script_dir/../../../Persona/Arthur/lib/pybot/pybot.py"
This should work out properly.
Regarding BASH_SOURCE, check out https://www.gnu.org/software/bash/manual/html_node/Bash-Variables.html
If you want the directory of start.sh to be cwd, you should call cd:
#!/bin/bash
script_dir=`dirname "${BASH_SOURCE[0]}"`
cd "$script_dir"
python "$script_dir/../../../Persona/Arthur/lib/pybot/pybot.py"

Crontab Python Script Execution (Can't find settings config file)

My Crontab -l
# m h dom mon dow command
SHELL=/bin/bash
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
00 8,20 * * * python /home/tomi/amaer/controller.py >>/tmp/out.txt 2>&1
My controller.py has config file settings.cfg also it uses other script in the folder it's located (I chmoded only controller.py)
The error
1;31mIOError^[[0m: [Errno 2] No such file or directory: 'settings.cfg'
I have no idea how to fix this? Please help me?
Edit: The part that read the config file
def main():
config=ConfigParser.ConfigParser()
config.readfp(open("settings.cfg"),"r")
As I initially wrote in my comment, this is because you are using relative path to the current working directory. However, that is not going to be the same when running all this via the cron executable rather than the python interpreter directly via the shebang.
Your current code would look for the "settings.cfg" in the current working directory which is where the cron executable resides, and not your script. Hence, you would need to change your code logic to using absolute paths by the help of the "os" built-in standard module.
Try to following line:
import os
...
def main():
config = ConfigParser.ConfigParser()
scriptDirectory = os.path.dirname(os.path.realpath(__file__))
settingsFilePath = os.path.join(scriptDirectory, "settings.cfg")
config.readfp(open(settingsFilePath,"r"))
This will get your the path of your script and then appends the "settings.cfg" with the appropriate dir separator for your operating system which is Linux in this particular case.
If the location of the config file changes any time in the future, you could use the argparse module for processing a command line argument to handle the config location properly, or even without it simply just using the first argument after the script name like sys.argv[1].
Your code is looking for settings.cfg in its current working directory.
This working directory will not be the same when cron executes the job, hence the error
You have two "easy" solutions:
Use an absolute path to the config file in your script (/home/tomi/amaer/config.cfg)
CD to the appropriate directory first in your crontab (cd /home/tomi/amaer/ && python /home/tomi/amaer/controller.py)
The "right" solution, though, would be to pass your script a parameter (or environment variable) that tells it where to look for the config file.
It's not exactly good practice to assume your config file will always be lying just next to your script.
You might want to have alook at this question: https://unix.stackexchange.com/questions/38951/what-is-the-working-directory-when-cron-executes-a-job

Categories