Git diff call in pre-commit throws "fatal: unable to read [SHA1]" - python

I am working in windows and attempting to run a git diff command in the pre-commit script (Python) of a repository. My Python call looks like this:
repo_dir = 'D:/git/current_uic/src/gtc/resource'
cmd = ['diff', '--name-only']
print(Popen(['git', '--git-dir={}'.format(repo_dir + '/.git'),
'--work-tree={}'.format(repo_dir)] + cmd,
stdin=PIPE, stdout=PIPE).communicate())
Whenever I go to commit in the "D:/git/current_uic/src/gtc" repo, I get the following:
fatal: unable to read 6ff96bd371691b9e93520e133ebc4d84c74cd0f6
Note that this is a pre-commit hook for the 'D:/git/current_uic/src/gtc' repository and that 'D:/git/current_uic/src/gtc/resource' is a submodule of 'D:/git/current_uic/src/gtc'. Also note that if I pop open Git bash and run the following:
git --git-dir=D:/git/current_uic/src/gtc/resource/.git
--work-tree=D:/git/current_uic/src/gtc/resource diff --name-only
or if I just run the script straight from Git bash I get exactly what I want, regardless of working directory.
Any ideas as to what is going on here?

The Problem:
Upon running a hook, Git sets some environment variables that are accessible by the hook script. The problem is that Git itself uses these environment variables, and the normal way in which Git sets/uses them seems to be overridden by the values set when the hook gets fired off. In this particular instance, the environment variable GIT_INDEX_FILE has been set to the path to the index file corresponding to the repository which had called the hook (D:/git/current_uic/src/.git/modules/gtc/index), causing a mismatch between the (incorrect) index and the (correct) change tree.
The Fix:
In the hook script, set the environment variable GIT_INDEX_FILE to the correct value before making any git calls. In this case, you could do the following:
set GIT_INDEX_FILE=D:/git/current_uic/src/.git/modules/gtc/modules/resource/index
git --git-dir=D:/git/current_uic/src/gtc/resource/.git
--work-tree=D:/git/current_uic/src/gtc/resource diff --name-only
Additional Info
More information about these Git environment variables and which hooks set them can be found here.

Got exactly same issue but using gitpython.
I solved it like this:
repo = git.Repo()
for submodule in repo.submodules:
back_index = os.getenv('GIT_INDEX_FILE')
os.environ['GIT_INDEX_FILE'] = submodule.module().index.path
commit = submodule.module().head.commit
print([item.a_path for item in commit.diff(None)])
os.environ['GIT_INDEX_FILE'] = back_index

Related

Pip install upgrade unable to remove temp files

In the course of maintaining a CLI utility, I want to add an update action that will grab the latest version of that package from PyPI and upgrade the existing installation.
$ cli -V
1.0.23
$ cli update
// many lines of pip spam
$ cli -V
1.0.24 // or etc
This is working perfectly on all machines that have Python installed system-wide (in C:\Python36 or similar), but machines that have Python installed as a user (in C:\users\username\AppData\Local\Programs\Python\Python36) receive this error as the old version is uninstalled:
Could not install packages due to an EnvironmentError: [WinError 5] Access is denied: 'C:\\Users\\username\\AppData\\Local\\Temp\\pip-uninstall-f5a7rk2y\\cli.exe'
Consider using the `--user` option or check the permissions.
I had assumed that this is due to the fact that the cli.exe called out in the error text is currently running when pip tries to remove it, however the path here is not to %LOCALAPPDATA%\Programs\Python\Python36\Scripts where that exe lives, but instead to %TEMP%. How is it allowed to move the file there, but not remove it once it's there?
including --user in the install args as recommended by the error message does not (contrary to the indication of an earlier edit of this question) resolve the issue, but moving the cli executable elsewhere does.
I'm hoping for an answer that:
Explains the underlying issue of failing to delete the executable from the TEMP directory, and...
Provides a solution to the issue, either to bypass the permissions error, or to query to see if this package is installed as a user so the code can add --user to the args.
While the question is fairly general, a MCVE is below:
def update(piphost):
args = ['pip', 'install',
'--index-url', piphost,
'-U', 'cli']
subprocess.check_call(args)
update('https://mypypiserver:8001')
As originally surmised, the issue here was trying to delete a running executable. Windows isn't a fan of that sort of nonsense, and throws PermissionErrors when you try. Curiously though, you can definitely rename a running executable, and in fact several questions from different tags use this fact to allow an apparent change to a running executable.
This also explains why the executable appeared to be running from %LOCALAPPDATA%\Programs\Python\Python36\Scripts but failing to delete from %TEMP%. It has been renamed (moved) to the %TEMP% folder during execution (which is legal) and then pip attempts to remove that directory, also removing that file (which is illegal).
The implementation goes like so:
Rename the current executable (Path(sys.argv[0]).with_suffix('.exe'))
pip install to update the package
Add logic to your entrypoint that deletes the renamed executable if it exists.
import click # I'm using click for my CLI, but YMMV
from pathlib import Path
from sys import argv
def entrypoint():
# setup.py's console_scripts points cli.exe to here
tmp_exe_path = Path(argv[0]).with_suffix('.tmp')
try:
tmp_exe_path.unlink()
except FileNotFoundError:
pass
return cli_root
#click.group()
def cli_root():
pass
def update(pip_host):
exe_path = Path(argv[0])
tmp_exe_path = exe_path.with_suffix('.tmp')
handle_renames = False
if exe_path.with_suffix('.exe').exists():
# we're running on Windows, so we have to deal with this tomfoolery.
handle_renames = True
exe_path.rename(tmp_exe_path)
args = ['pip', 'install',
'--index-url', piphost,
'-U', 'cli']
try:
subprocess.check_call(args)
except Exception: # in real code you should probably break these out to handle stuff
if handle_renames:
tmp_exe_path.rename(exe_path) # undo the rename if we haven't updated
#cli_root.command('update')
#click.option("--host", default='https://mypypiserver:8001')
def cli_update(host):
update(host)
Great solution provided by the previous commenter: Pip install upgrade unable to remove temp files by https://stackoverflow.com/users/3058609/adam-smith
I want to add to remarks that made the code work for me (using python 3.8):
Missing parentheses for the return of the entrypoint function (however, the function I'm pointing to is not decorated with #click.group() so not sure if that's the reason)
def entrypoint():
# setup.py's console_scripts points cli.exe to here
tmp_exe_path = Path(argv[0]).with_suffix('.tmp')
try:
tmp_exe_path.unlink()
except FileNotFoundError:
pass
>>> return cli_root() <<<
Missing with_suffix('.exe') when attempting the rename in the update function. If I use the original code I get FileNotFoundError: [WinError 2] The system cannot find the file specified: '..\..\..\updater' -> '..\..\..\updater.tmp'
def update(pip_host):
exe_path = Path(argv[0])
tmp_exe_path = exe_path.with_suffix('.tmp')
handle_renames = False
if exe_path.with_suffix('.exe').exists():
# we're running on Windows, so we have to deal with this tomfoolery.
handle_renames = True
>>> exe_path.with_suffix('.exe').rename(tmp_exe_path) <<<
...

Setting $PATH via a command with tox

Currently using tox to test a python package, and using a python library (chromedriver-binary) to install chromedriver.
This library creates a script (chromedriver-path) which when called outputs the PATH where chromedriver is installed. The usual way to use this is to run:
export PATH=$PATH:`chromedriver-path`
I've tried the following without success in tox.ini
setenv=
PATH = {env:PATH}{:}`chromedriver-path`
This errors as expected:
FileNotFoundError: [Errno 2] No such file or directory: 'chromedriver': 'chromedriver'
Implying that the setenv command is never called/run.
commands=
export PATH=$PATH:`chromedriver-path
This fails with:
ERROR: InvocationError for command could not find executable export
How do I make this work?
Commands can't change their parent processes' environment variables, and thus can't change the environment variables of subsequent commands launched by forking that parent; they can only set environment variables for themselves or their own children.
If you were able to collect the output of chromedriver-path before starting tox, this would be moot. If it's only available in an environment tox itself creates, then things get a bit more interesting.
One approach you can follow is to wrap the commands that need this path entry in a shim that adds it. Consider changing:
commands=
py test ...
to:
commands=
sh -c 'PATH=$PATH:$(chromedrive-path); exec "$#"' _ py test ...

git executable not found in python

I was trying to clone a git repo with access key, but when I am trying to run it, It throws an exception saying git executable not found.
But i have installed git and the in_it.py shows correct path "C:\Program Files\Git\bin" Also I have installed gitpython to use the library in python
here's my code...
import git
git.Git("D:/madhav/myrep/").clone("#github.com:myrepo/scripts")
========= and it throws the following exception =================
Traceback (most recent call last): File
"C:\Users\1096506\Desktop\gitclone.py", line 1, in <module>
from git import Repo File "C:\Users\1096506\AppData\Local\Programs\Python\Python36-32\lib\site-packages\git\__init__.py",
line 84, in <module>
refresh() File "C:\Users\1096506\AppData\Local\Programs\Python\Python36-32\lib\site-packages\git\__init__.py",
line 73, in refresh
if not Git.refresh(path=path): File "C:\Users\1096506\AppData\Local\Programs\Python\Python36-32\lib\site-packages\git\cmd.py",
line 293, in refresh
raise ImportError(err) ImportError: Bad git executable. The git executable must be specified in one of the following ways:
- be included in your $PATH
- be set via $GIT_PYTHON_GIT_EXECUTABLE
- explicitly set via git.refresh()
All git commands will error until this is rectified.
This initial warning can be silenced or aggravated in the future by setting the
$GIT_PYTHON_REFRESH environment variable. Use one of the following values:
- quiet|q|silence|s|none|n|0: for no warning or exception
- warn|w|warning|1: for a printed warning
- error|e|raise|r|2: for a raised exception
Example:
export GIT_PYTHON_REFRESH=quiet
I had the same issue. What I did is:
I went to: System Properties -> Environment Variables
On System Variables Section I clicked Path, Edit and Move Up.
Environment Variables
Edit and Moved Up two places from the bottom
Error occurs because git is not in the path. So its not able to import git module.
Couple of ways to resolve it.
As suggested above adding the git binary path to environment variable path.
If git is not being used directly in the module and its only a dependent module import thats throwing this exception before importing git we could add
os.environ["GIT_PYTHON_REFRESH"] = "quiet"
and import git after this line, this would suppress the error caused due to git import
Had the same problem got it to work thanks to Muthukumaran. Just make Muthukumaran answer more clear.
Follow these steps:
import os
os.environ["GIT_PYTHON_REFRESH"] = "quiet"
import git
See if you have installed Git in the OS.
If not install git first this will solve your error.
Centos
sudo yum -y install git
Ubuntu/Debian
sudo apt-get install git
Mac Os
sudo brew install git
This solved my problem.
Make sure you're not in an inaccessible directory on *nix, such as when you've just been root and then done a su username
you may still be in root's home folder and that will trigger this error (assuming you have the correct environment variables set, and have sourced the .profile or .bashrc etc with source ~/.bashrc )
which git
/usr/bin/git
I was getting this error even after setting the environment:
in ~/.bashrc
# for bench
PATH=$PATH:/usr/bin/git
export PATH
GIT_PYTHON_GIT_EXECUTABLE=/usr/bin/git
export GIT_PYTHON_GIT_EXECUTABLE
cd
and it's working
$ bench --version
WARN: Command not being executed in bench directory
5.3.0
I came across similar problem recently and installing git followed by restarting Windows Powershell CommandLine solved the problem. May it helps.
For those who are using a Lambda layer with it. It worked adding as the comment above says just adding GIT_PYTHON_REFRESH=quiet as an environment variable.
Execute GIT_PYTHON_REFRESH=quiet in your terminal and then try to run the code.

How to execute git command in a identified path?

I want to execute git command in python program.
I have tried
os.system("git-command")
As we know, git command can be executed correctly only in the directories which contains repositories. I have tried to print current path and this path is not what I hope for, it does not contains repositories.
Now my question is how to execute git command in a identified path.
Use the subprocess module; pick one of the functions that suits your needs (based on what output you need). The functions all take a cwd argument that lets you specify the directory to operate in:
import subprocess
output = subprocess.check_output(['git', 'status'], cwd='/path/to/git/workingdir')
Using GitPython:
from git import *
repo = Repo("/path/to/repo")
git = repo.git
print git.status()

git folder download utility with python?

hello is there an good utility or package that handles git folder download ?
example
getsomething = {
'htmlpurifier' : 'http://repo.or.cz/w/htmlpurifier.git'
}
for key in vendors:
# someutility.get(http://repo.or.cz/w/htmlpurifier.git,htmlpurifier)
someutility.get(vendors[key],key)
# get http://repo.or.cz/w/htmlpurifier folder to /htmlpurifier on localstorage ?
if there is anything similar?
I prefer to use git commands directly and wrap it using subprocess module.
How ever, if you are looking for modules to interact with Git, I can think of
dulwich : http://www.samba.org/~jelmer/dulwich/docs/index.html
git-python: http://gitorious.org/projects/git-python/
For git-python, particularly, please look at class : Repo. It has a function:
fork_bare(path, **kwargs)
Fork a bare git repository from this repo
path is the full path of the new repo (traditionally ends with name.git)
options is any additional options to the git clone command
Returns git.Repo (the newly forked repo)
Also you can checkout: http://packages.python.org/GitPython/0.3.2/tutorial.html#using-git-directly
git = repo.git
git.checkout('head', b="my_new_branch")
GitPython is a python library used to interact with git repositories
-- GitPython docs
If by "git folder download" you mean clone the Git repository this should do it:
from git import Repo
repo_url = "http://repo.or.cz/w/htmlpurifier.git"
local_dir = "/Users/user1/gitprojects/"
Repo.clone_from(repo_url, local_dir)

Categories