I have a project with multiple dependencies installed using virtualenv and pip. I want to run my project on a server which does not have pip installed. Unfortunately, installing pip is not an option.
Is there a way to export my required packages and bundle them with my project? What is the common approach in this situation?
Twitter uses pex files to bundle Python code with its dependencies. This will produce a single file. Another relevant tool is platter which also aims to reduce the complexity of deploying Python code to a server.
Another alternative is to write a tool yourself which creates a zip file with the Python and dependencies and unzips it in the right location on the server.
In Python 3.5 the module zipapp was introduced to improve support for this way of deploying / using code. This allows you to manage the creation of zip files containing Python code and run them directly using the Python interpreter.
#Simeon Visser's answer is a good way to deal with that. Mine is to build my python project with buildout.
This may be outside of scope of the question, but if your need is deploying applications to servers with their dependencies, have a look at virtualization and linux containers.
It is by far the most used solution to this problem, and will work with any type of application (python or not), and it is lightweight (the performance hit of LXC is not noticeable in most cases, and isolating apps is a GREAT feature).
Docker containers, besides being trendy right now, are a very convenient way to deploy applications without caring about dependencies, etc...
The same goes for development envs with vagrant.
Related
I wish to place a python program on GitHub and have other people download and run it on their computers with assorted operating systems. I am relatively new to python but have used it enough to have noticed that getting the assorted versions of all the included modules to work together can be problematic. I just discovered the use of requirements.txt (generated with pipreqs and deployed with the command pip install -r /path/to/requirements.txt) but was very surprised to notice that requirements.txt does not actually state what version of python is being used so obviously it is not the complete solution on its own. So my question is: what set of specifications/files/something-else is needed to ensure that someone downloading my project will actually be able to run it with the fewest possible problems.
EDIT: My plan was to be guided by whichever answer got the most upvotes. But so far, after 4 answers and 127 views, not a single answer has even one upvote. If some of the answers are no good, it would be useful to see some comments as to why they are no good.
Have you considered setting up a setup.py file? It's a handy way of bundling all of your... well setup into a single location. So all your user has to do is A) clone your repo and B) run pip install . to run the setup.py
There's a great stack discussion about this.
As well as a handle example written by the requests guy.
This should cover most use cases. Now if you want to make it truly distributable then you'll want to look into setting it up in PyPi, the official distribution hub.
Beyond that if you're asking how to make a program "OS independent" there isn't a one size fits all. It depends on what you are doing with your code. Requires researching how your particular code interacts with those OS's etc.
There are many, many, many, many, many, many, many ways to do this. I'll skate over the principles behind each, and it's use case.
1. A python environment
There are many ways to do this. pipenv, conda, requirments.txt, etc etc.
With some of these, you can specify python versions. With others, just specify a range of python versions you know it works with - for example, if you're using python 3.7, it's unlikely not to support 3.6; there's only one or two minor changes. 3.8 should work as well.
Another similar method is setup.py. These are generally used to distribute libraries - like PyInstaller (another solution I'll mention below), or numpy, or wxPython, or PyQt5 etc - for import/command line use. The python packaging guide is quite useful, and there are loads of tutorials out there. (google python setup.py tutorial) You can also specify requirements in these files.
2. A container
Docker is the big one. If you haven't heard of it, I'll be surprised. A quick google of a summary comes up with this, which I'll quote part of:
So why does everyone love containers and Docker? James Bottomley, formerly Parallels' CTO of server virtualization and a leading Linux kernel developer, explained VM hypervisors, such as Hyper-V, KVM, and Xen, all are "based on emulating virtual hardware. That means they're fat in terms of system requirements."
Containers, however, use shared operating systems. This means they are much more efficient than hypervisors in system resource terms. Instead of virtualizing hardware, containers rest on top of a single Linux instance. This means you can "leave behind the useless 99.9 percent VM junk, leaving you with a small, neat capsule containing your application,"
That should summarise it for you. (Note you don't need a specific OS for containers.)
3. An executable file
There are 2 main tools that do this at the time of writing. PyInstaller, and cx_Freeze. Both are actively developed. Both are open source.
You take your script, and the tool compiles it to bytecode, finds the imports, copies those, and creates a portable python environment that runs your script on the target system without the end user needing python.
Personally, I prefer PyInstaller - I'm one of the developers. PyInstaller provides all of its functionality through a command line script, and supports most libraries that you can think of - and is extendable to support more. cx_Freeze requires a setup script.
Both tools support windows, Linux, macOS, and more. PyInstaller can create single file exes, or a one folder bundle, whereas cx_Freeze only supports one folder bundles. PyInstaller 3.6 supports python 2.7, and 3.5-3.7 - but 4.0 won't support python 2. cx_Freeze has dropped python 2 support as of the last major release (6.0 I think).
Anyway, enough about the tools features; you can look into those yourself. (See https://pyinstaller.org and https://cx-freeze.readthedocs.io for more info)
When using this distribution method, you usually provide source code on the GitHub repo, a couple of exes (one for each platform) ready for download, and instructions on how to build the code into an executable file.
The best tool I have used so far for this is Pipenv. Not only it unifies and simplifies the whole pip+virtualenv workflow for you, developer, but it also guarantees that the exact versions of all dependencies (including Python itself) are met when other people run your project with it.
The project website does a pretty good job at explaining how to use the tool, but, for completeness sake, I'll give a short explanation here.
Once you have Pipenv installed (for instance, by running pip install --user pipenv), you can go to the directory of your project and run pipenv --python 3.7, so Pipenv will create a new virtualenv for your project, create a Pipfile and a Pipfile.lock (more on them later). If you go ahead and run pipenv install -r requirements.txt it will install all your packages. Now you can do a pipenv shell to activate your new virtualenv, or a pipenv run your_main_file.py to simply run your project.
Now let's take a look at the contents of your Pipfile. It should be something resembling this:
[packages]
Django = "*"
djangorestframework = "*"
iso8601 = "*"
graypy = "*"
whitenoise = "*"
[requires]
python_version = "3.7"
This file has the human-readable specifications for the dependencies of your project (note that it specifies the Python version too). If your requirements.txt had pinned versions, your Pipfile could have them too, but you can safely wildcard them, because the exact versions are stored in the Pipfile.lock. Now you can run things like pipenv update to update your dependencies and don't forget to commit Pipfile and Pipfile.lock to your VCS.
Once people clone your project, all they have to do is run pipenv install and Pipenv will take care of the rest (it may even install the correct version of Python for them).
I hope this was useful. I'm not affiliated in any way with Pipenv, just wanted to share this awesome tool.
If your program is less about GUI, or has a web GUI, then you can share the code using Google Colaboratory.
https://colab.research.google.com/
Everyone can run it with the same environment. No need for installation.
In case converting all your python scripts into one executable can help you, then my answer below would help ...
I have been developing a large desktop application purely in python since 3 years. It is a GUI-based tool built on top of pyqt library (python-bindings of QT C++ framework).
I am currently using "py2exe" packaging library : is a distutils extension which allows to build standalone Windows executable programs (32-bit and 64-bit) from Python scripts; all you have to do is to:
install py2exe: 'pip install py2exe'
Create a setup.py script: It is used to specify the content of the final EXE (name, icon, author, data files, shared libraries, etc ..)
Execute: python setup.py py2exe
I am also using "Inno Setup" software to create installer: Creating shortcuts, setting environment variables, icons, etc ...
I'll give you a very brief summary of some of the existing available solutions when it comes to python packaging you may choose from (knowledge is power):
Follow the guidelines provided at Structuring Your Project, these conventions are widely accepted by python community and it's usually a good starting point when newcomers start coding in python. By following these guidelines pythonists watching your project/source at github or other similar places will know straightaway how to install it. Also, uploading your project to pypi as well as adding CI by following those rules will be painless.
Once your project is structured properly according to standard conventions, the next step might be using some of the available freezers, in case you'd like to ship to your end-users a package they can install without forcing them to have python installed on their machines. Be aware though these tools won't provide you any code protection... said otherwise, extracting the original python code from the final artifacts would be trivial in all cases
If you still want to ship your project to your users without forcing them to install any dev dependency and you do also care about code protection so you don't want to consider any of the existing freezers you might use tools such as nuitka, shedskin, cython or similar ones. Usually reversing code from the artifacts produced by these tools isn't trivial at all... Cracking protection on the other hand is a different matter and unless you don't provide a physical binary to your end-user you can't do much about it other than slowing them down :)
Also, in case you'd need to use external languages in your python project another classic link that comes to mind would be https://wiki.python.org/moin/IntegratingPythonWithOtherLanguages, adding the build systems of such tools to CI by following rules of 1 would be pretty easy.
That said, I'd suggest stick to bulletpoint 1 as I know that will be more than good enough to get you started, also that particular point should cover many of the existing use-cases for python "standard" projects.
While this is not intended to be a full guide by following those you'll be able to publish your python project to the masses in no time.
I think you can use docker with your python https://github.com/celery/celery/tree/master/docker
kindly follow the files and I think you can figure out the way to make your docker file for your python scripts!
Because it is missing from the other answers, I would like to add one completely different aspect:
Unit testing. Or testing in general.
Usually, it is good to have one known good configuration. Depending on what the dependencies of the program are, you might have to test different combinations of packages. You can do that in an automated fashion with e.g. tox or as part of a CI/CD pipeline.
There is no general rule of what combination of packages should be tested, but usually python2/3 compatability is a major issue. If you have strong dependencies on packages with major version differences, you might want to consider testing against these different versions.
I wish to place a python program on GitHub and have other people download and run it on their computers with assorted operating systems. I am relatively new to python but have used it enough to have noticed that getting the assorted versions of all the included modules to work together can be problematic. I just discovered the use of requirements.txt (generated with pipreqs and deployed with the command pip install -r /path/to/requirements.txt) but was very surprised to notice that requirements.txt does not actually state what version of python is being used so obviously it is not the complete solution on its own. So my question is: what set of specifications/files/something-else is needed to ensure that someone downloading my project will actually be able to run it with the fewest possible problems.
EDIT: My plan was to be guided by whichever answer got the most upvotes. But so far, after 4 answers and 127 views, not a single answer has even one upvote. If some of the answers are no good, it would be useful to see some comments as to why they are no good.
Have you considered setting up a setup.py file? It's a handy way of bundling all of your... well setup into a single location. So all your user has to do is A) clone your repo and B) run pip install . to run the setup.py
There's a great stack discussion about this.
As well as a handle example written by the requests guy.
This should cover most use cases. Now if you want to make it truly distributable then you'll want to look into setting it up in PyPi, the official distribution hub.
Beyond that if you're asking how to make a program "OS independent" there isn't a one size fits all. It depends on what you are doing with your code. Requires researching how your particular code interacts with those OS's etc.
There are many, many, many, many, many, many, many ways to do this. I'll skate over the principles behind each, and it's use case.
1. A python environment
There are many ways to do this. pipenv, conda, requirments.txt, etc etc.
With some of these, you can specify python versions. With others, just specify a range of python versions you know it works with - for example, if you're using python 3.7, it's unlikely not to support 3.6; there's only one or two minor changes. 3.8 should work as well.
Another similar method is setup.py. These are generally used to distribute libraries - like PyInstaller (another solution I'll mention below), or numpy, or wxPython, or PyQt5 etc - for import/command line use. The python packaging guide is quite useful, and there are loads of tutorials out there. (google python setup.py tutorial) You can also specify requirements in these files.
2. A container
Docker is the big one. If you haven't heard of it, I'll be surprised. A quick google of a summary comes up with this, which I'll quote part of:
So why does everyone love containers and Docker? James Bottomley, formerly Parallels' CTO of server virtualization and a leading Linux kernel developer, explained VM hypervisors, such as Hyper-V, KVM, and Xen, all are "based on emulating virtual hardware. That means they're fat in terms of system requirements."
Containers, however, use shared operating systems. This means they are much more efficient than hypervisors in system resource terms. Instead of virtualizing hardware, containers rest on top of a single Linux instance. This means you can "leave behind the useless 99.9 percent VM junk, leaving you with a small, neat capsule containing your application,"
That should summarise it for you. (Note you don't need a specific OS for containers.)
3. An executable file
There are 2 main tools that do this at the time of writing. PyInstaller, and cx_Freeze. Both are actively developed. Both are open source.
You take your script, and the tool compiles it to bytecode, finds the imports, copies those, and creates a portable python environment that runs your script on the target system without the end user needing python.
Personally, I prefer PyInstaller - I'm one of the developers. PyInstaller provides all of its functionality through a command line script, and supports most libraries that you can think of - and is extendable to support more. cx_Freeze requires a setup script.
Both tools support windows, Linux, macOS, and more. PyInstaller can create single file exes, or a one folder bundle, whereas cx_Freeze only supports one folder bundles. PyInstaller 3.6 supports python 2.7, and 3.5-3.7 - but 4.0 won't support python 2. cx_Freeze has dropped python 2 support as of the last major release (6.0 I think).
Anyway, enough about the tools features; you can look into those yourself. (See https://pyinstaller.org and https://cx-freeze.readthedocs.io for more info)
When using this distribution method, you usually provide source code on the GitHub repo, a couple of exes (one for each platform) ready for download, and instructions on how to build the code into an executable file.
The best tool I have used so far for this is Pipenv. Not only it unifies and simplifies the whole pip+virtualenv workflow for you, developer, but it also guarantees that the exact versions of all dependencies (including Python itself) are met when other people run your project with it.
The project website does a pretty good job at explaining how to use the tool, but, for completeness sake, I'll give a short explanation here.
Once you have Pipenv installed (for instance, by running pip install --user pipenv), you can go to the directory of your project and run pipenv --python 3.7, so Pipenv will create a new virtualenv for your project, create a Pipfile and a Pipfile.lock (more on them later). If you go ahead and run pipenv install -r requirements.txt it will install all your packages. Now you can do a pipenv shell to activate your new virtualenv, or a pipenv run your_main_file.py to simply run your project.
Now let's take a look at the contents of your Pipfile. It should be something resembling this:
[packages]
Django = "*"
djangorestframework = "*"
iso8601 = "*"
graypy = "*"
whitenoise = "*"
[requires]
python_version = "3.7"
This file has the human-readable specifications for the dependencies of your project (note that it specifies the Python version too). If your requirements.txt had pinned versions, your Pipfile could have them too, but you can safely wildcard them, because the exact versions are stored in the Pipfile.lock. Now you can run things like pipenv update to update your dependencies and don't forget to commit Pipfile and Pipfile.lock to your VCS.
Once people clone your project, all they have to do is run pipenv install and Pipenv will take care of the rest (it may even install the correct version of Python for them).
I hope this was useful. I'm not affiliated in any way with Pipenv, just wanted to share this awesome tool.
If your program is less about GUI, or has a web GUI, then you can share the code using Google Colaboratory.
https://colab.research.google.com/
Everyone can run it with the same environment. No need for installation.
In case converting all your python scripts into one executable can help you, then my answer below would help ...
I have been developing a large desktop application purely in python since 3 years. It is a GUI-based tool built on top of pyqt library (python-bindings of QT C++ framework).
I am currently using "py2exe" packaging library : is a distutils extension which allows to build standalone Windows executable programs (32-bit and 64-bit) from Python scripts; all you have to do is to:
install py2exe: 'pip install py2exe'
Create a setup.py script: It is used to specify the content of the final EXE (name, icon, author, data files, shared libraries, etc ..)
Execute: python setup.py py2exe
I am also using "Inno Setup" software to create installer: Creating shortcuts, setting environment variables, icons, etc ...
I'll give you a very brief summary of some of the existing available solutions when it comes to python packaging you may choose from (knowledge is power):
Follow the guidelines provided at Structuring Your Project, these conventions are widely accepted by python community and it's usually a good starting point when newcomers start coding in python. By following these guidelines pythonists watching your project/source at github or other similar places will know straightaway how to install it. Also, uploading your project to pypi as well as adding CI by following those rules will be painless.
Once your project is structured properly according to standard conventions, the next step might be using some of the available freezers, in case you'd like to ship to your end-users a package they can install without forcing them to have python installed on their machines. Be aware though these tools won't provide you any code protection... said otherwise, extracting the original python code from the final artifacts would be trivial in all cases
If you still want to ship your project to your users without forcing them to install any dev dependency and you do also care about code protection so you don't want to consider any of the existing freezers you might use tools such as nuitka, shedskin, cython or similar ones. Usually reversing code from the artifacts produced by these tools isn't trivial at all... Cracking protection on the other hand is a different matter and unless you don't provide a physical binary to your end-user you can't do much about it other than slowing them down :)
Also, in case you'd need to use external languages in your python project another classic link that comes to mind would be https://wiki.python.org/moin/IntegratingPythonWithOtherLanguages, adding the build systems of such tools to CI by following rules of 1 would be pretty easy.
That said, I'd suggest stick to bulletpoint 1 as I know that will be more than good enough to get you started, also that particular point should cover many of the existing use-cases for python "standard" projects.
While this is not intended to be a full guide by following those you'll be able to publish your python project to the masses in no time.
I think you can use docker with your python https://github.com/celery/celery/tree/master/docker
kindly follow the files and I think you can figure out the way to make your docker file for your python scripts!
Because it is missing from the other answers, I would like to add one completely different aspect:
Unit testing. Or testing in general.
Usually, it is good to have one known good configuration. Depending on what the dependencies of the program are, you might have to test different combinations of packages. You can do that in an automated fashion with e.g. tox or as part of a CI/CD pipeline.
There is no general rule of what combination of packages should be tested, but usually python2/3 compatability is a major issue. If you have strong dependencies on packages with major version differences, you might want to consider testing against these different versions.
I'm currently launching my website and I want my Python script to be run. However, it does not work when I run it because it depends on 5 libraries. How do you link them to your code?
For example, I use pymysql to write data to my host's database. However, it does not recognise pymysql.
Is there a way to download all of the packages once on the server and then being able to access them? How to link to them in the code?
Many thanks !
There are many ways to do this, the easiest way is probably to use pip freeze > requirements.txt to get a list (requirements.txt) of the dependencies that you have installed for your project (which, if you're running under a virtualenv, is only those installed for your project).
If you have installed multiple libraries for your interpreter that you don't need, you can remove them from the list, or create the list manually.
You can make pip install all the libraries again on your host by doing pip -r requirements.txt.
The best way is to package your project and deploy it on your remote server.
The best practices nowadays is described in “Packaging and Distributing Projects” from the Python Packaging Authority
You can follow the Sample Python project available on GitHub.
Another way is to create a library or an application using a project template. One of the famous ones is cookiecutter-pypackage from Audrey Roy Greenfeld Cookiecutter.
This is the info you're looking for:
https://www.namecheap.com/support/knowledgebase/article.aspx/9587/29/how-to-run-python-scripts
They give two solutions - the cPanel solution and the SSH solution.
First let me explain the current situation:
We do have several python applications which depend on custom (not public released ones) as well as general known packages. These depedencies are all installed on the system python installation. Distribution of the application is done via git by source. All these computers are hidden inside a corporate network and don't have internet access.
This approach is bit pain in the ass since it has the following downsides:
Libs have to be installed manually on each computer :(
How to better deploy an application? I recently saw virtualenv which seems to be the solution but I don't see it yet.
virtualenv creates a clean python instance for my application. How exactly should I deploy this so that usesrs of the software can easily start it?
Should there be a startup script inside the application which creates the virtualenv during start?
The next problem is that the computers don't have internet access. I know that I can specify a custom location for packages (network share?) but is that the right approach? Or should I deploy the zipped packages too?
Would another approach would be to ship the whole python instance? So the user doesn't have to startup the virutalenv? In this python instance all necessary packages would be pre-installed.
Since our apps are fast growing we have a fast release cycle (2 weeks). Deploying via git was very easy. Users could pull from a stable branch via an update script to get the last release - would that be still possible or are there better approaches?
I know that there are a lot questions. Hopefully someone can answer me r give me some advice.
You can use pip to install directly from git:
pip install -e git+http://192.168.1.1/git/packagename#egg=packagename
This applies whether you use virtualenv (which you should) or not.
You can also create a requirements.txt file containing all the stuff you want installed:
-e git+http://192.168.1.1/git/packagename#egg=packagename
-e git+http://192.168.1.1/git/packagename2#egg=packagename2
And then you just do this:
pip install -r requirements.txt
So the deployment procedure would consist in getting the requirements.txt file and then executing the above command. Adding virtualenv would make it cleaner, not easier; without virtualenv you would pollute the systemwide Python installation. virtualenv is meant to provide a solution for running many apps each in its own distinct virtual Python environment; it doesn't have much to do with how to actually install stuff in that environment.
I have developed a python CGI application which works just fine on my development box. My hosting provider however gives me little control of its server: I use a lot of custom stuff in my python environment (like sqlalchemy and mako templating) and the servers python version is far too old to be used. My question is: how do I set up a isolated, complete, standalone python environment in my home directory and install my required modules to run my app? ...the easiest way ;)
how do I set up a isolated, complete, standalone python environment in my home directory
mkdir /home/me/.local (if it doesn't already exist. You don't have to use .local but it is becoming the normal place to put this)
mkdir /home/me/.local/src (ditto)
cd /home/me/.local/src
wget http://python.org/ftp/python/2.6.4/Python-2.6.4.tgz
gzip -d Python-2.6.4.tgz
tar xf Python-2.6.4.tar
cd Python-2.6.4
./configure --prefix=/home/me/.local
make
make install
Hopefully you can now run Python:
/home/me/.local/bin/python
Install packages you need using the usual setup.py script, but with your version of Python:
/home/me/.local/bin/python setup.py install
Set hashbang on CGI files to use your version of Python:
#!/home/me/.local/bin/python
Consider migrating your application to WSGI if you can. You can of course still deploy WSGI apps through CGI using a wsgiref.handlers.CGIHandler for now, but in the future when you have a less woeful hosting environment you'll be able to deploy using a much less wasteful server interface such as mod_wsgi.
In your shoes, I'd use pyinstaller to bundle Python, my code, and all my dependencies into one installer executable, upload it, and run it. Just be sure to use the SVN trunk of pyinstaller -- the "released" version is WAY obsolete.
Be aware that with SQLAlchemy and everything else, with CGI you may find out you're really slow, since you're paying the full startup price everytime the page gets visited. But if CGI is all you can afford, I guess that's the way I would try to cope!-)
This looks like a job for virtualenv. From the site:
Also, what if you can't install packages into the global site-packages directory? For instance, on a shared host.
This looks to be right up your alley.
I am on Dreamhost's shared plan. Besides CGI, they also offer FastCGI which makes things much faster than CGI. You should check if your hosting provider offers that. Or maybe they provide Passenger for Ruby that you could piggyback your Python with.
If you compile Python yourself, keep in mind the UCS setting if you try to install precompiled packages and experience failures. See the StackOverflow article. Dreamhost's wiki has some advice on how you could build and deploy Python yourself on their servers; you might want to adapt to your needs.