I want to locally recompile/reinstall a package that has already been downloaded via OPAM, but without downloading it again.
opam reinstall seems to always re-download the package, and I see no option to disable it.
Here are a few reasons one might want to perform this local re-installation:
The local sources have been modified, and the person wants to apply the modifications, without having to manually rebuild everything from the original source code;
There is currently no Internet connection, or it is slow/capped.
opam will try to keep in sync downloaded package with the upstream one. That means, that if package is in local cache and it doesn't differ from the upstream package, then it wouldn't be downloaded.
If you want to change source code locally, then you need to pin the package.
Other option is to create your own repository and add it to your opam. Your local repository can contain all the packages or only several that you're interested. For handling local repositories there is an opam-admin tool.
Creating your own repository is not a very easy task, so I would suggest you to use pin command, and pin packages, that you want to have locally, to the specified local path.
Example (requires opam 1.2 or later)
opam source lwt.2.4.8
opam pin add lwt lwt.2.4.8
lwt was chosen arbitrary, just because it is short. The first command will download the sources of the specified version and put them in folder lwt.2.4.8 along with the opam file. The second will force opam tool to use this particular folder as a source for lwt package.
Related
Problem
I am attempting to install Python 2.7.16, openpyxl, and pyinstaller onto a Windows 10 machine that is offline for security reasons. To clarify, I have a mapped network drive on there from which I can transfer the files I need to use.
Question
What is the best way to go about this? I currently have a .msi Python installation file directly from their website. The packages I need are packaged as .tar.gz files. I currently have those on my windows machine, but do not want to proceed until I know for sure what I need to do. Also, do I need to do anything for dependencies? If so, how do I find the dependencies for the packages I need?
Side Notes
The version of Python (2.7.16) comes with pip. Not sure if that makes a difference. Downloading and transferring things requires me to ask my admin, for him to download the files, and then transfer them to my drive so I can have them on my computer. If able, I would like to do this in as little attempts as possible.
Useful links
Python: https://www.python.org/downloads/release/python-2716/
openpyxl: https://pypi.org/project/openpyxl/#files
pyinstaller: https://pypi.org/project/PyInstaller/#files
My solution would be to seek out the offline versions of the python and pip installer and follow this guide
Also a great tip: try the complete procedure (the installing of the required software) on a seperate pc which you have disconnected and do the installation. Note everything you have to do to get it working and use those instruction on your originally intended machine. This will prevent you from having to go back and forth and scratch your head while installing on the target machine.
Please note that I have NO idea how python works and this is just a hunch from me as a programmer.
Installing Python and packages on an Offline Machine: A Comprehensive Guide
The Environment
Let us begin by defining the environment in which this guide may be of some great use. If your situation can be described by one or more of the following, you might have great results following this guide...
The machine you are developing on is offline. (No connection to the internet)
You need to develop and run Python on the machine that is completely offline.
If this sounds like you, read the following cases in which a few minor details may make a big difference in getting you started.
Case1:
You are not allowed to plug in any external media devices into the offline machine. This includes but is not limited to a USB, CD, floppy disk, or any other removable media that may be of some use in helping you transfer Python files to the offline machine.
You are allowed to map a network drive (somewhere else on the local network). This would fix the problem mentioned in number one with removable media.
Answer: In this case, just proceed with the guide, as this was my case and I will explain in detail how I solved my problem.
Case2:
There is no physical way to transfer files onto the development machine that is offline.
Answer: If this is your case, you need to get in touch with the admin team who handles the software on your development machine. Direct them to this guide to proceed.
Let's Get Started
Warning A:
The following must be performed on a computer with an internet connection. It is impossible to download things from any website without an internet connection.
Warning B:
There is a longer way, and there is a shorter way to do the following. To avoid the longer way, you must be able to install python on a different machine that is online. This can be the same machine that you are using to download the packages and python version, or it can even be a home machine. This can be any machine in the world that is on the internet. It's sole purpose will be to help you identify the dependencies of each package.
Installing Python
Visit the python website and identify the version you want. 2.7.9 and up is recommended for this guide. Download the file for your specific system.
Python 2.7.9 : https://www.python.org/downloads/release/python-279/
Python 3.7.3 : https://www.python.org/downloads/release/python-373/
The reason I provided Python 2.7.9 is because that is the earliest 2.7.x version that comes with pip (a package manager).
Visit the python package index to locate the packages you will be using in your python project. https://pypi.org/
Search the package you need, go to the downloads, and get the (.tar.gz) file. Not the .whl files unless you know what you are doing with those.
Tip: If you want to keep track of the packages you are installing, I suggest you put them all in one folder somewhere you can find, or just write them down on paper.
Unpack the .tar.gz package files. You can get rid of the .tar.gz once you unpack them as they will not needed any longer.
Install the version of python that you downloaded for your system in step 1 above.
(This may just be running the .msi file for windows or unpacking some files for linux) If you are not sure how, just look at this brilliant guide
https://realpython.com/installing-python/
Now you should be able to go to your terminal and type "python" and get the python interpreter to open up. If you get a "cannot find python command" you need to setup your path variable.
Windows guide: https://geek-university.com/python/add-python-to-the-windows-path/
Linux guide: https://www.tutorialspoint.com/python/python_environment.htm
Your python installation is done! And your packages should also be ready to install!
Installing Python Packages
What you need to know here is that MOST all python packages have dependencies, which are other packages which packages need installed before they can be installed. If you need more explanation on dependencies, read here: https://www.fullstackpython.com/application-dependencies.html
Before proceeding be sure to add the Python/Scripts folder to your path variable too or pip will not work. Follow this link for instructions. https://appuals.com/fix-pip-is-not-recognized-as-an-internal-or-external-command/
Install packages using pip install [package_name] for every package you need, on your machine that is on the internet, and then do a pip freeze to see all the packages installed.
Once you can see all the packages installed, which will include the dependencies for the ones you ran pip install on, you need to manually download these dependencies from the python package index https://pypi.org/ just like you did with the regular packages.
Moving Offline
Once you have identified all the packages you will need, and all of their dependencies, you will need to download them, unpack all of them, and move them into one folder, which I will call "OFFLINE_SETUP_FOLDER".
To be clear:
The packages we installed before was only to find out the dependencies we were going to need. You do not have to re-download the packages you have already downloaded before running pip install. You should only need to download the dependencies you have found during the pip freeze command.
Finally you need to copy into the "OFFLINE_SETUP_FOLDER" your python installation file, be it a .msi file for windows, or the .tar file for linux.
Your "OFFLINE_SETUP_FOLDER" should contain the following...
In the following, package can be the name of any package that you downloaded, and the a and b inpackage1a and package1b just represent dependencies for that package. These file names are just examples for packages
python.msi (installation file for python)
/package1 (normal package folder)
/package1a (package dependency folder)
/package1b (package dependency folder)
/package2 (normal package folder)
/package3 (normal package folder)
/package3a (package dependency folder)
Once this is complete, you need to move that folder onto the machine that is completely offline form the network.
Then run the installation for python as you did before and install it on the machine. Do no forget to setup the path variable. Refer back to the Installing Python section if needed.
Open your terminal or CMD and CD into the "OFFLINE_SETUP_FOLDER".
Now you need to CD into each individual package folder, and run this command: python setup.py install and let it run.
If the package install fails, it will be because one of the dependencies has not been installed. If this is the case, CD into the dependency that is says is missing, and run python setup.py install in there first.
Keep repeating these steps until all packages and dependencies have been installed.
This is the end of this python guide for installing python on an offline machine. I hope this helped :)
I've noticed that after the packages required written in "requirements.txt" were installed they are not installed anymore every time I push changes into the Heroku application I'm working, so I was assuming that those files were not modified anymore.
I then changed a file in /app/.heroku/python/lib/python2.7/site-packages/target_library/target_file but when I do git push the file goes back to its original state, although the library is not being installed again.
Is there a way to avoid libraries to be reseted or any workaround?
Based on the last answer.
or fork the library on GitHub and install the forked version.
Here are the few steps I've tested and it worked for me:
1- Fork the package repo on GitHub.
2- Edit it and change whatever you need.
3- Now remove the original package name from your requirments.txt and replace it with git+https://github.com/you-github-username/forked-edited-package.git
Now it should simply install the edited package to your Heroku dyno when you deploy the project
No this can't possibly work. Heroku will always install the packages directly from PyPI and won't know anything about your modifications. I don't know why you say they aren't installed again - on the contrary, they are.
Are you sure you really need to do this? It's a fairly unusual thing to do. If you are sure you do, then the only thing to do is to either for the files into your own project, or fork the library on GitHub and install the forked version.
We are trying to build into an Open Source ocaml project a way to automatically kick off a Travis CI build & test session when any of the 3rd party OPAM packages the project depends on get changed. If there was some clean way to get a change notification, then programmatically we could touch a file in a test branch and do a pull request which would start the Travis CI process to test compatibility so that our end users don't trip over the issue. We're trying to avoid wasting OPAM resources polling.
Thank you for your time!
opam.ocaml.org is a mirror of the OPAM repo https://github.com/ocaml/opam-repository, therefore you can periodically pull it and check the new commits.
You may have to be careful of silent source code change of packages, since their sources are out of the OPAM repo. If packages are OPAM registered without their checksums, you have to periodically check their sources themselves, too.
Can I use apt-get or other package managers in Cloud Foundry buildpacks or .profile scripts that come with apps; and if I can, how to do it? I expect to do it the same way as in a dockerfile, but it doesn't work with or without sudo in my case.
Can I use apt-get or other package managers in Cloud Foundry buildpacks or .profile scripts that come with apps; and if I can, how to do it?
No. Running apt-get or a package manager would typically require root access and you do not get root access when the build pack runs or when your application runs (this is a difference w/Docker).
That said, you can do anything that doesn't require root access, so if you found a package manager that installed in the vcap user's home directory and didn't need root then you could use that.
It depends on what you're trying to install, but in some cases you can work around this by downloading the .deb or .rpm file and manually extracting the binaries. This typically works OK for things like shared libraries. Just download the precompiled binary that matches your stack (cflinuxfs2 == Ubuntu Trusty). For other things, you can build your own binaries from source. This is what the build pack's do, see binary-builder.
Hope that helps!
On my system, ArchLinux x86_64, I have installed the package opam-git which was working the last time I used it.
The following command opam update fail with this message:
opam update
=-=- Updating package repositories =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
[ERROR] curl: code 404 while downloading https://opam.ocaml.org/1.3/urls.txt
[ERROR] Could not update repository default
In this link https://github.com/ocaml/opam-repository/issues/6231 they say:
it is 2.0.dev now
What should I do to resolve my problem?
This is a git devel version of opam, did I get this right? Current opam release is 1.2.
And it is from Arch AUR?
It looks like AUR published an inconsistent opam dev state from git.
Once the git is consistent (pull request done) file a bug report, wait for the update, and do a new opam install from AUR.
Or just rely on the current versions from ocaml.org, IMO the premier source.
BTW when encountering problems with your local .opam directory and the compiled ocaml packages: the whole stuff can be deleted and reinstalled without any side effects (provided your own source is somewhere else). This is the functional paradigm.
/Str.