This may be a silly question, but I would still like to ask:
I am developing a project using Django, CherryPy, and Nginx. I noticed that a file requirement.txt is usually created to indicate the packages and versions installed in the development environment. Suppose the directory of the virtual environment is /home/me/project/python2Venv.
When I deploy my Django project (tango) into production, the project is copied to the production directory:
sudo cp -r /home/me/project/tango /webapps/tango
For the virtual environment, may I just copy the whole directory using the following command or I should install each of the packages into the production environment again according to requirement.txt?
sudo cp -r /home/me/project/python2Venv /webapps/tango/python2Venv
I think virtualenv uses absolute paths in some files so recreating the env and installing the packages via requirements.txt would be more safe.
In my opinion, it is recommended to install the packages with requirements.txt. Copying directory, can end up being a nightmare.
Say in Update 1:
You have 4 packages each with a specific version(pkg1-ver1, pkg2-ver1, pkg3-ver1, pkg-ver1).
In Update 2:
You have upgraded one package to its new version(pkg1-ver2). With requirements.txt you would just upgrade that one package. Instead of the copying all the packages(Although, i am not sure how well copying of the directory would work).
Hope this helps !
You should install packages with the file requirements.txt.
Or you can use virtualenvwrapper. It helps to clone virtual environments locally easily such as cpvirtualenv, rmvirtualenv, etc.
Related
I am deploying a Django app using Heroku.
When I run
git push heroku master
in my terminal I get the following error:
Could not find a version that satisfies the requirement command-not-found==0.3"
When I run
sudo apt-get install command-not-found
I find that command-not-found is version 20.04.2. However, pip freeze tells me command-not-found is version 0.3.
command-not-found doesn't seem to exist on PyPI, but it is a package in Ubuntu and Debian repositories. It doesn't look like anything that your application should depend on, and it certainly doesn't belong on Heroku.
I suspect
you're trying to create your dependencies file after the fact, by simply doing pip freeze > requirements.txt, and
that you're either not working in a virtual environment or you created your virtual environment with system packages.
This is an antipattern that will cause several packages that your application doesn't actually need to be included in your requirements.txt. In this case it is even including Python packages that come from system packages and aren't meant to be installed from PyPI. Your requirements.txt should contain only your actual dependencies.
Instead of creating it with pip freeze after the fact, add things to that file before, and install them into your virtual environment with the same pip install -r requirements.txt command that you'll use in production. I also very strongly urge you to use a virtual environment.
In this case, I suggest you edit your requirements.txt and remove anything you don't actually need, commit, and redeploy.
I'm coming from a .Net and Node background where packages from the package manager e.g. NuGet or NPM get installed into a specific /packages folder.
I'm learning python and when I do a pip install my packages either end up in a global store or I can tell pip to put them into a specific place.
Is it good practice to put them into a separate folder or does that upset the Zen of python?
I want to do this so I can docker ignore that folder and then pip install them inside the docker container based on my production operating system from a requirements.txt file.
Is there a good reason I shouldn't do this? Why does Python not do this as default as it seems to be a clean and portable approach to package management?
Usually you install them in the default location or within a python virtual environment.
virtual environment
Do the virtual environment when you don't want to clutter up your default python environment.
Good day.
I'm a newbie to Django and I have a slight confusion:
When deploying my Django app, do I need to deploy it with all the Python 'come-with' modules, or the hosts already have them installed.
Also, I installed PIL for image manipulation. Would they also have it installed or i have to find a way to install it on their servers. Thanks in advance
do I need to deploy it with all the Python 'come-with' modules
Never do that. It might conflict with the dependencies on the server. Instead issue the following command to create a dependency file (requirements.txt).
pip freeze > requirements.txt (issue this command where manage.py is located)
On the server create a new virtual environment. Now copy django project to the server (you can do this using git clone or just plain old Filezilla). Activate virtual environment. Then change you current working directory to the where manage.py is located. to install all the dependencies issue the following command.
pip install -r requirements.txt
This will install the required dependencies on on server.
I have django project running on my machine in virtualenv. Is there a way I can deploy my project on Heroku directly? I followed steps mentioned in heroku documentation but i am kind of confused with req.txt since my project already have req.txt in virtualenv. I am new to django heroku techs. Any guidance is highly appreciated.
my project already have req.txt in virtualenv
You should not have req.txt in virtualenv. You should have requirements.txt in your project repository. requirements.txt is just a list of modules that need to be installed in the virtualenv. You create and activate a new virtualenv, then you run pip install -r requirements.txt, and it installs everything you need in the virtualenv. So requirements.txt is not part of the virtualenv, it's more like a description of how to setup the virtualenv.
If this is not clear, you may find my article, virtualenv demystified, useful.
The requirements.txt file defines what python dependencies Heroku will install. Generally speaking, what you use locally will be the same as your local development machine.
If there are differences, you may opt to have an additional file locally that contains local, development-specific packages (for example django-debug-toolbar).
First you will activate your virtual environment and then go to project root and run the command
pip freeze > requirements.txt
This will automatically add all the dependencies of your local machine in requirements.txt. Once you push the file heroku will automatically detect the changes and install them.
We had a working project with git, and our instructor moved our project over to mercurial after making some changes.
I pulled the new project and started it up under a new folder.
I tried running a virtualenv for the new project but I get: Requirement already satisfied
I would usually then run $ . bin/activate but I cannot find a bin folder.
How do I get a virtualenv setup for this project at this point?
The place where you have your project isn't necessarily the place where you have the environment. Did you have the environment in git too?
Perhaps what you need to do (in case you don't have a versioned environment) is recreate the environment (virtualenv environment), install the dependencies (pip install -r req.txt) and then activate it (source path/to/environment/bin/activate).
Good luck.
Ok
Try this an awesome link to How to install django in virtual environment .
http://ayarshabeer.com/post/50973941605/install-multiple-django-version-using-virtualenvwrapper
Use the following steps
virtualenv virenv_name --no-site-packages - create new virtual environment in git
pip install -r requirements.pip - It can be used for install tools in
(requirements.pip files)
yolk -l - It will used for list install files
source git/virenv_name/bin/activate - Activate virtualenv
deactivate - Deactivate virtualenv