hashin 0.4

Edits your requirements.txt by hashing them in

Helps you write your requirements.txt with hashes so you can install with pip install --require-hashes -r ...

If you want to add a package or edit the version of one you’re currently using you have to do the following steps:

1. Go to pypi for that package

2. Download the .tgz file

3. Possibly download the .whl file

4. Run pip hash downloadedpackage-1.2.3.tgz

5. Run pip hash downloadedpackage-1.2.3.whl

6. Edit requirements.txt

This script does all those things. Hackishly wonderfully so.

A Word of Warning!

The whole point of hashing is that you vet the packages that you use on your laptop and that they haven’t been tampered with. Then you can confidently install them on a server.

This tool downloads from PyPI (over HTTPS) and runs pip hash on the downloaded files.

You should check that the packages that are downloaded are sane and not tampered with. The way you do that is to run hashin as normal but with the --verbose flag. When you do that it will print where it downloaded the relevant files and those files are not deleted. For example:

$ hashin --verbose bgg /tmp/reqs.txt
https://pypi.python.org/pypi/bgg/json
* Latest version for 0.22.1
* Found URL https://pypi.python.org/packages/2.7/b/bgg/bgg-0.22.1-py2-none-any.whl
*   Re-using /var/folders/1x/2hf5hbs902q54g3bgby5bzt40000gn/T/bgg-0.22.1-py2-none-any.whl
*   Hash e5172c3fda0e8a42d1797fd1ff75245c3953d7c8574089a41a219204dbaad83d
* Found URL https://pypi.python.org/packages/source/b/bgg/bgg-0.22.1.tar.gz
*   Re-using /var/folders/1x/2hf5hbs902q54g3bgby5bzt40000gn/T/bgg-0.22.1.tar.gz
*   Hash aaa53aea1cecb8a6e1288d6bfe52a51408a264a97d5c865c38b34ae16c9bff88
* Editing /tmp/reqs.txt

You might not have time to go through the lines one by one but you should be aware that the vetting process is your responsibility.

Installation

This is something you only do or ever need in a development environment. Ie. your laptop:

pip install hashin

How to use it

Suppose you want to install futures. You can either do this:

hashin futures

Which will download the latest version tarball (and wheel) and calculate their pip hash and edit your requirements.txt file.

Or you can be specific about exactly which version you want:

hashin "futures==2.1.3"

Suppose you don’t have a requirements.txt right there in the same directory you can do this:

hashin "futures==2.1.3" stuff/requirementst/prod.txt

If there’s not output. It worked. Check how it edited your requirements files.

Filtering releases by Python version

Some requirements have many releases built for different versions of Python and different architectures. These hashes aren’t useful in some cases, if those wheels don’t work with your project. hashin can filter on the Python version to skip these extraneous hashes.

For example, the cffi package offers wheels built for many versions of CPython from 2.6 to 3.5. To select only one of them, you can use the --python-version option:

hashin "cffi==1.5.2" --python-version 3.5

If you need to support multiple versions, you can pass this option multiple times:

hashin "cffi==1.5.2" --python-version 2.7 --python-version 3.5

hashin will expand these Python versions to a full list of identifers that could be found on PyPI. For example, 3.5 will expand to match any of 3.5, py3, py3.5, py2.py3, or cp3.5. You can also specify these exact identifiers directly, if you need something specific.

The source release is always automatically included. pip will use this as a fallback in the case a suitable wheel cannot be found.

Runnings tests

Simply run:

python setup.py test

Debugging

To avoid having to install hashin just to test it or debug a feature you can simply just run it like this:

touch /tmp/whatever.txt
python hashin.py --verbose Django /tmp/whatever.txt

History

This program is a “fork” of https://pypi.python.org/pypi/peepin peepin was a companion to the program peep https://pypi.python.org/pypi/peep/ but the functionality of peep has been put directly into pip as of version 8.

Future

If this script proves itself to work and be useful, I hope we can put it directly into pip.

Version History

0.4

• Add filtering of package releases by Python version.

0.3

• Issue a warning for users of Python before version 2.7.9.

0.2

• Last character a single newline. Not two.

0.1

• First, hopefully, working version.