I will format my pc and i would like to somehow collect all the python modules that i have currently and package them (zip or rar etc) / or create an index file of them, so that when i'm done formatting the pc i can reinstall them all in one go, either by using the package/or by using the index created to pip install them all in a batch.
Is there any python module that allows to do that?
Use pip
pip freeze > requirements.txt
This will save the names of all your installed python modules to a file called requirements.txt.
Then when you want to install them again run the following command.
pip install -r requirements.txt
Using a package manager like this is good practice to get into, especially if you use a code repository, so you dont upload all the dependencies to the repo.
If you are not already doing so, its a good idea to use a virtual environment for your python projects.
This will create a unique python environment for each of your projects, keeping each project self contained.
Yes - pip. Using pip freeze will give you the list of all the installed modules. Next all you need to do is to install all that modules by running pip install -r your_file_with_modules_list.
Related
I am a beginner in python. I have done a website using django, flask, xml, wtforms and also i have used some API python modules too. The website was successfully created and working well in local machine.
But if i want to run in an another python available machine, i am in the need of install all my above mentioned modules manually.
Do we have something similar to gradle, maven or ant which will download/install the required modules during my first run?
Kindly help me.
One way is to freeze your current local python installations into a requirements.txt file and then install everything in one go in another machine.
$ pip freeze > requirements.txt
copy the requirements file into another machine,
install python and then ...
$ pip install -r requirements.txt
I would like to easily export one Python project from one PC to other. When I created the project, I used a virtual environment in order to avoid problems with different package versions.
What I did was to just copy the project folder and paste it in the destination PC. Once I opened the project with Pycharm, I activated the virtual environment with project_path/venv/Scripts/activate, but when I tried to execute any Script, it said it didn´t find the modules.
Which is the workflow I should follow in order to create projects and be able to run them from multiple PC-s without needing to install all the dependencies?
Since you did not specify your Python version I will provide a solution working for both Python 2.x and 3.x.
My suggestion is to create a requirements.txt file containing all your requirements.
This file can be easily prepared using the output from the command:
pip freeze
Then you can paste the output in your requirements.txt file and when you are going to install your Python code on another PC you can simply:
pip install -r requirements.txt
To install your requirements again.
Depending on your project it could be possible, for example, to create a single EXE file (if you are using Windows machines) but more detailed is needed if this is the case.
In case you are using Python 3 the method that is at the moment arguably more popular in the Python community is Pipenv.
Here's its relevant documentation.
And here you can read a simple example of a workflow.
if you are using python3 then use pipenv. It will automatically create Pipfile and Pipfile.lock. That will insure reinstalling dependencies on different machine will have the same packages.
basic and helpful commands:
pipenv shell # activate virutalenv
pipenv install # will install dependencies in Pipfile
pipenv install requests # will install requests lib. and will auto update Pipfile and Pipfile.lock
I have a pytest test, let's call it test.py. I used to run this test outside of virtualenv; now I'm trying to run it inside a virtualenv sandbox.
The project is structured like this:
~/project/test # where test.py and all virtualenv files live
~/project/mylibrary
test.py imports from mylibrary. In the past, this worked because I have the code in ~/project/mylibrary installed into /usr/lib/python2.7/dist-packages/mylibrary.
I can't run virtualenv with the --system-site-packages flag. I also can't move the code from ~/project/mylibrary into the ~/project/test folder. How can I get access to the code in mylibrary inside my virtualenv?
You don't need to do anything special - as long as you are working inside a virtualenv, python setup.py install will automatically install packages into
$VIRTUAL_ENV/lib/python2.7/site-packages
rather than your system-wide
/usr/lib/python2.7/dist-packages
directory.
In general it's better to use pip install mylibrary/, since this way you can neatly uninstall the package using pip uninstall mylibrary.
If you're installing a working copy of some code that you're developing, it might be a good idea to install it in "editable" mode using pip install -e mylibrary/, which creates a link to your source directory so that your installed module gets updated as you edit the code.
The easiest way would be to add the directory containing the library to your sys.path
I want to output the requirements.txt for my Python 3 project in PyCharm. Any ideas?
Try the following command:
pip freeze > requirements.txt
Pigar works quite well I just tested it
https://github.com/damnever/pigar
The answer above with pip freeze will only work properly if you have set up a virtualenv before you started installing stuff with pip. Otherwise you will end up with requirements which are "surplus to requirements". It seems that pigar goes and looks at all your import statements and also looks up the versions currently being used. Anyway, if you have the virtualenv set up before you start it will all be cleaner, otherwise pigar can save you. It looks in subdirectories too.
open the terminal in Pycharm and type in this command:
pip freeze > requirements.txt
and the requirements.txt will be automatically created
Surely this post is a bit old but the same I contribute with what I learned, to generate the requirements.txt we can do it in three ways, as far as I know:
using FREEZE
pip freeze > requirements.txt
Before running the command be sure that the virtual environments is activated because
the command will be executed in the same folder as the project.A file requirements.txt with Python dependencies will be generated in the same folder as the execution.
If you use this command all requirements will be collected from the virtual environment. If you need to get requirements used only in the current project scope then you need to check next options.
using DEEPHELL
pip install --user dephell
using PIPREQS
pip install pipreqs
pipreqs /path/to/project
Note
Why to use pipreqs? Because pip freeze will collect all dependencies from the environments. While pipreqs will collect requirements used only in the current project!
plus freeze only saves the packages that are installed with pip install and saves all packages in the environment.
If you like to generate requirements.txt without installing the modules use pipreqs
If there were other ways to do it always grateful to continue learning :)
You can do it in Pycharm by going to Settings and project interpreter. Select all the Packages with their Version and latest. Then copy all this data into a MS word document. The MS word will treat it as a table. Delete the middle column of this table. Now copy all this data into a notepad++. Search for double spaces ' ' or a tab and replace it with '=='. Save this file as a requirements.txt. It will work
Lets say a developer is working on a project when he realizes he needs to use some package.
He uses pip to install it. Now, after installing it, would a the developer write it down as a dependency in the requirements file / setup.py?
What does that same dev do if he forgot to write down all the dependencies of the project (or if he didn't know better since he hasn't been doing it long)?
What I'm asking is what's the workflow when working with external packages from the PyPi?
The command:
pip freeze > requirements.txt
will copy all of the dependencies currently in your python environment into requirements.txt. http://pip.readthedocs.org/en/latest/reference/pip_freeze.html
It depends on the project.
If you're working on a library, you'll want to put your dependencies in setup.py so that if you're putting the library on PyPi, people will be able to install it, and its dependencies automatically.
If you're working on an application in Python (possibly web application), a requirements.txt file will be easier for deploying. You can copy all your code to where you need it, set up a virtual environment with virtualenv or pyvenv, and then do pip install -r requirements.txt. (You should be doing this for development as well so that you don't have a mess of libraries globally).
It's certainly easier to write the packages you're installing to your requirements.txt as soon as you've installed them than trying to figure out which ones you need at the end. What I do so that I never forget is I write the packages to the file first and then install with pip install -r.
pip freeze helps if you've forgotten what you've installed, but you should always read the file it created to make sure that you actually need everything that's in there. If you're using virtualenv it'll give better results than if you're installing all packages globally.