Basically I am writing a script to reset a django webapp completely. In this script, I want to reset the database, and there is a command to do it from django extensions. Unfortunately, I haven't been able to run it programatically. It works fine when I run it via command line, but it just won't execute when I try programatically.
I have tried using os.system and subprocess.
I have also tried using management.call_command('reset_db'), but it keeps saying that there isn't a command called reset_db. I have checked to make sure the django_extensions is in my installed apps, so I have no idea why that isn't working.
Does anyone know how I could fix this? Thank you!
Also I am using python3, the most recent version of django I believe, and it is a MYSQL server that I am trying to delete.
I can't know without seeing your way of invocation directly, but my guess is the script's not running in the virtualenv. Here are some debug notes:
./manage.py --help | grep reset_db: Does this output anything?
./manage.py shell_plus
Then try:
from django.core.management import call_command
call_command('reset_db', '--help')
Anything then?
Also within ./manage.py shell_plus, try import django_extensions
Outside of the shell, try this: pip show django, pip django-extensions.
If it doesn't show those (e.g. WARNING: Package(s) not found: django-extension) and you think they're already installed, try this:
which python, which pip. Are you using venv, virtualenv, virtualenvwrapper, pipenvorpoetry`?
Try env | grep VIRT, do you see a VIRTUAL_ENV? If not you may need to make one.
When you run the script, you need to have your environmental variables set so you hook in to your site packages. In poetry we can do poetry run ./manage.py ourscript or poetry run ./ourscript.py without needing to be sourced. But we can also easily drop into virtualenv via poetry shell.
If you created an environment like virtualenv -ppython3.8 .venv, you can either do:
source .venv/bin/activate, ./myscript.py, rr you can try .venv/bin/python ./myscript.py
Related
im on macbook old version El Capitan 10.11.6 and my python script is 147bytes just for auto shutdown program but when i try to boundle it pyinstaller filename.py it done almost everything and end up with (codesign failure). do someone know how to solve this?
Try the following command in your terminal, type: sudo codesign -f -s followed by your script name test.py Make sure you are in your script file directory by using cd path to your file folder.
After that, you can run pyinstaller test.py However, I am using macOS Monterey Version 12.6 and am not sure if it will work on your current version. In fact, I don't even know how that command makes it work, but it works for me. If your app is a windowed app, such as the Tkinter app, your system may prevent it from opening; in that case, use the following command to disable the security system sudo spctl --master-disable . then you will see a new option available in your macOS Settings under Security; down there it says Allow app from: App Store, App Store and identified developer; and at last, you will see a new option "Anywhere" which wasn't there before; check that, and your app will work perfectly. hope helped
The Flask official website says that we can run a Flask application by
$ export FLASK_APP=hello.py
$ flask run
The second command doesn't work for me.
$ flask run
Command 'flask' not found, but can be installed with:
sudo apt install python3-flask
Instead this works
python3 -m flask run
How can I make the second command works? If I run sudo apt install python3-flask, will I get two installations of flask?
Can the two commands be combined into one command without using environment variable?
Bear with me as I will try to explain the different pieces and how they all interconnect. export FLASK_APP=hello.py is setting an operating system environment variable called FLASK_APP and is simply pointing to the entry file to start your flask application. This is no different than setting any other environment variable on your operating system. Now the flask team has provided everyone with a command called flask run which can be used to start up your flask application and this command will use the value set within your FLASK_APP environment variable when it attempts to start your flask server. So the reason why your python3 -m flask run command works is because you're telling your operating system's install of python to run the flask run command as a script, which is how this command is intended to be invoked.
For reference:
-m mod : run library module as a script (terminates option list)
Additionally, python attempts to resolve modules from it's sys.path environment variable and it looks in the following order of directories to resolve the requested module:
The current directory where the script has been invoked. This is why you can always import modules contained in the same directory as one another.
The value of your PYTHONPATH environment variable
The standard library directory on your path
Lastly, the site packages directory, i.e. your third party packages like flask
Now the reason your flask run command didn't initially work is because python couldn't find flask within any of the four locations listed above. However, once you gave the -m python knew to look in your site-packages directory for flask and was able to find said module.
For reference you can see where python is looking to resolve modules by printing out the sys.path variable to the console:
import sys
print(sys.path)
Ok so that answers the first part of your first question, now as for the second part of your first question:
"If I run sudo apt install python3-flask, will I get two installations of flask?"
Yes, this would install flask globally on your system and I would highly advise against this as you can mess up your system pretty badly if you're not careful. So how do I avoid messing with my system level python configurations?
Virtualenv to the rescue, Virtual environments allow you to have a sandboxed area to play around with libraries. With the worst case scenario being you blow them away and start fresh if you screwed something up, without affecting your Operating System's install of python. You should have a one to one relationship between each python project and virtual environment. If you use virtualenv I highly suggest looking into Virtualenvwrapper which wraps virtualenv with easier to remember commands. Although I think all the cool kids are using pipenv now so you may want to look into that as well, I will leave that decision up to you. What's nice is once you've activated your virtual environment and are developing you can just use flask run since your virtual environment will be on your python path.
As for your second question: "Can the two commands be combined into one command without using environment variable?"
No you would still need to set the FLASK_APP environment variable to use flask run since it looks for the value of that environment variable to start your flask server. Perhaps you could try something like:
FLASK_APP=hello.py flask run
on the command line and see if that helps you, but you're still setting the FLASK_APP environment variable. Alternatively, you could just start the entry file for your flask server directly, with a:
python hello.py
I know that was a lot, but hopefully that helps clarify things for you!
I want to debug an application using Python and Flask in VSCode. I have installed Flask and the app runs perfectly fine through cmd. But, when I try to debug it through VSCode, it gives the following error:
cd 'c:\Users\Aditi\CleanHandymanApp';
${env:FLASK_APP}='NewApp'; ${env:PYTHONIOENCODING}='UTF-8';
${env:PYTHONUNBUFFERED}='1'; & 'C:\Users\Aditi\envs\CleanHandymanApp\Scripts\python.exe'
'c:\Users\Aditi\.vscode\extensions\ms-python.python-2018.10.1\pythonFiles\experimental\ptvsd_launcher.py' '--client' '--host'
'localhost' '--port' '63143' '-m' 'flask' 'run' '--no-debugger' '--no-reload'
No module named flask
Can you please help me.
This error message can occur if you installed the python3 version of flask but Visual Studio Code tries to run your project with python2.
Make sure to select the correct version of python in the editor. This can be done by running the command Python: Select Interpreter from the Command Palette (Ctrl+Shift+P).
Activate your virtualenv and run
pip3 install -r requirements.txt
to reinstall all packages inside the venv.
For some reason VS Code thought I was missing all my packages the first time I debugged even though the app was running fine locally.
Sometimes you can get this error if you loaded Flask into a folder which has sub-files. For instance, if you loaded flask into the parent folder with the virtual shell instance but you're running your code in the child file (let's say parent is called crypto_files and inside that is a python source code file called blockchain.py ), then in order to get flask to run properly you'd have to run the file like this:
python crypto_files/blockchain.py
This allows your machine to see Flask running inside crypto_files but also run blockchain.py .
OR, it's possibly you could just reload Flask into the sub(child)file... blockchain.py and then you'd run it from within the subfile.
This complication is mainly due to modern "virtual instances" and shells which are basically like creating a virtual computer-machine inside your ACTUAL hard machine. Flask does this to avoid running everywhere, and since Flask is modular it allows each of your projects to run different modular configurations of Flask to suit each project precisely. The alternative would be awful: you'd have to load the fattest version of Flask with dozens of add-ons for each project, and so all your git and all your projects would have tons of extra code. Flask is built to be very small at the core to avoid this problem (too verbose!).
If you have installed flask in virtual environment, you should have activated it first.
source /path to env dir/bin/activate #in linux
workon 'name of env' #windows
Another option is add sys.path.append('d:/programas/anaconda3/lib/site-packages') in c:\Users\Aditi.vscode\extensions\ms-python.python-2018.10.1\pythonFiles\experimental\ptvsd_launcher.py
Being that "d:/programas/anaconda3/lib/site-packages" should be modified by your local python packages.
Use this command in the terminal instead of selecting run code:
python3 "insert your file name here without the quotes"
e.g.: python3 example.py
I had a variant of the issue mentioned by #confusius. I had installed both Python 3.9 and Python 3.10. I had added Flask to Python 3.10. I had been using one vscode workspace which had selected Python 3.10. I started another project in a different vscode workspace and it had selected Python 3.9 by default, which I didn't notice because I thought it would select the same Python I had already selected in the other workspace.
I am using Python 3.5.2 version on Windows 7 and tried using python3 app.py. I am getting this error message:
'python3' is not recognized as an internal or external command,
operable program or batch file.
Is there any specific cause about why the python3 command is not working?
I also verified that the PATH is added to environment variables.
There is no python3.exe file, that is why it fails.
Try:
py
instead.
py is just a launcher for python.exe. If you have more than one python versions installed on your machine (2.x, 3.x) you can specify what version of python to launch by
py -2 or
py -3
You can also try this:
Go to the path where Python is installed in your system. For me it was something like C:\Users\\Local Settings\Application Data\Programs\Python\Python37
In this folder, you'll find a python executable. Just create a duplicate and rename it to python3. Works every time.
Python3.exe is not defined in windows
Specify the path for required version of python when you need to used it by creating virtual environment for your project
Python 3
virtualenv --python=C:\PATH_TO_PYTHON\python.exe environment
Python2
virtualenv --python=C:\PATH_TO_PYTHON\python.exe environment
then activate the environment using
.\environment\Scripts\activate.ps1
Yes, I think for Windows users you need to change all the python3 calls to python to solve your original error. This change will run the Python version set in your current environment. If you need to keep this call as it is (aka python3) because you are working in cross-platform or for any other reason, then a work around is to create a soft link. To create it, go to the folder that contains the Python executable and create the link. For example, this worked in my case in Windows 10 using mklink:
cd C:\Python3
mklink python3.exe python.exe
Use a (soft) symbolic link in Linux:
cd /usr/bin/python3
ln -s python.exe python3.exe
In my case I have a git hook on commit, specified by admin. So it was not very convenient for me to change the script (with python3 calls).
And the simplest workaround was just to copy python.exe to python3.exe.
Now I could launch both python and python3.
If python2 is not installed on your computer, you can try with just python instead of python3
For Python 27
virtualenv -p C:\Python27\python.exe django_concurrent_env
For Pyton36
virtualenv -p C:\Python36\python.exe django_concurrent_env
Enter the command to start up the server in that directory:
py -3.7 -m http.server
I had a related issue after installing windows 11, where python3 in cmd would open the windows store. I was able to sort it out between this post and this other one. In short, I reinstalled python and made sure to add it to PATH. Then, in settings, Apps > Apps & Features > App Execution aliases. Here, all I had to do was make sure that every single python .exe (including idle and pip) were turned off EXCEPT FOR the python3.exe alias. Now it works like a charm.
FWIW:
The root of this issue is not with you or with python. Apparently, Microsoft wanted to make installing python easier for young kiddos getting interested in coding, so they automatically add an executable to PATH. For those of us that already have this executable, it can cause these issues.
Found out instead press the play button the top right and it should work in visual studios:
Do not disable according to first answer
Saying python3 in the command will not work by default.
After figuring out the problem with the modules (Solution): https://youtu.be/paRXeLurjE4
Summary:
To import python modules in case of problem to import modules:
Hover over python in search:
Click open in folder
Hover over and right click
click properties
copy everything in path before \python.exe
close those windows
For cmd (administrator):
cd --path that was copied--
then python -m pip install --upgrade pip
cd Scripts
pip install "Name of Package" such as pip install --module (package) --
Im on win10 and have 3.7, 3.8 and 3.10 installed.
For me "python" launches version 3.10 and does not accept commands (like -3.7), "py" launches newest version but does accept commands, and "python3" does nothing.
Uninstalled 3.10 and "python" now does nothing, and "py" launches 3.8.
I am unable to add a comment, but the mlink option presented in this answer above https://stackoverflow.com/a/55229666/8441472 by #Stanislav preserves cross-platform shebangs at the top of scripts (#!/usr/bin/env python3) and launches the right python.
(Even if you install python from python.org, Windows will direct you to the app marketplace nowadays if you type python3 on the command line. If you type python on the same cli it will launch the python.org version repl. It leads to scripts that generate no output, but more likely silently failed completely. I don't know ho common this is but have experienced it on a couple of different devices)
If you have this at the top of your script to ensure you launch python3 and don't feel like editing everything you own, it is not a bad approach at all... lol.
I have an account to a computing cluster that uses Scientific Linux. Of course I only have user access. I'm working with python and I need to run python scripts, so I need to import some python modules. Since I don't have root access, I installed a local python copy on my $HOME with all the required modules. When I run the scripts on my account (hosting node), they run correctly. But in order to submit jobs to the computing queues (to process on much faster machines), I need to submit a bash script that has a line that executes the scripts. The computing cluster uses SunGrid Engine. However when I submit the bash script, I get an error that the modules I installed can't be found! I can't figure out what is wrong. I hope if you can help.
You could simply call your python program from the bash script with something like: PYTHONPATH=$HOME/lib/python /path/to/my/python my_python_script
I don't know how SunGrid works, but if it uses a different user than yours, you'll need global read access to your $HOME. Or at least to the python libraries.
First, whether or not this solution works for you depends heavily on how the cluster is set up. That said, the general solution to your problem is below. If the compute cluster has access to the same files as you do in your home directory, I see no reason why this would not work.
You need to be using a virtualenv. Install your software inside that virtualenv along with any additional python packages you need. Then in your batch bash script, provide the full path to the python interpreter within that virtualenv.
Note: to install python packages inside your virtualenv, you need to use the pip instance that is in your virtualenv, not the system pip.
Example:
$ virtualenv foo
$ cd foo
$ ./bin/pip install numpy
Then in your bash script:
/path/to/foo/bin/python /path/to/your/script.py
Have you tried to add these in your python code:
import sys
sys.path.append("..")
from myOtherPackage import myPythonFile
This works very well for my code when I run it on Cluster and I wanted to call my "myPythonFile" from other package "myOtherPackage"