commit 668efd063a9cde08078063d188ab5af7a64c0290 Author: jan Date: Mon Feb 11 01:17:07 2019 -0800 initial commit diff --git a/LICENSE.md b/LICENSE.md new file mode 100644 index 0000000..175443c --- /dev/null +++ b/LICENSE.md @@ -0,0 +1,595 @@ +GNU General Public License +========================== + +_Version 3, 29 June 2007_ +_Copyright © 2007 Free Software Foundation, Inc. <>_ + +Everyone is permitted to copy and distribute verbatim copies of this license +document, but changing it is not allowed. + +## Preamble + +The GNU General Public License is a free, copyleft license for software and other +kinds of works. + +The licenses for most software and other practical works are designed to take away +your freedom to share and change the works. By contrast, the GNU General Public +License is intended to guarantee your freedom to share and change all versions of a +program--to make sure it remains free software for all its users. We, the Free +Software Foundation, use the GNU General Public License for most of our software; it +applies also to any other work released this way by its authors. You can apply it to +your programs, too. + +When we speak of free software, we are referring to freedom, not price. Our General +Public Licenses are designed to make sure that you have the freedom to distribute +copies of free software (and charge for them if you wish), that you receive source +code or can get it if you want it, that you can change the software or use pieces of +it in new free programs, and that you know you can do these things. + +To protect your rights, we need to prevent others from denying you these rights or +asking you to surrender the rights. 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But this requirement does not apply if +neither you nor any third party retains the ability to install modified object code +on the User Product (for example, the work has been installed in ROM). + +The requirement to provide Installation Information does not include a requirement to +continue to provide support service, warranty, or updates for a work that has been +modified or installed by the recipient, or for the User Product in which it has been +modified or installed. Access to a network may be denied when the modification itself +materially and adversely affects the operation of the network or violates the rules +and protocols for communication across the network. + +Corresponding Source conveyed, and Installation Information provided, in accord with +this section must be in a format that is publicly documented (and with an +implementation available to the public in source code form), and must require no +special password or key for unpacking, reading or copying. + +### 7. Additional Terms + +“Additional permissions” are terms that supplement the terms of this +License by making exceptions from one or more of its conditions. Additional +permissions that are applicable to the entire Program shall be treated as though they +were included in this License, to the extent that they are valid under applicable +law. If additional permissions apply only to part of the Program, that part may be +used separately under those permissions, but the entire Program remains governed by +this License without regard to the additional permissions. + +When you convey a copy of a covered work, you may at your option remove any +additional permissions from that copy, or from any part of it. (Additional +permissions may be written to require their own removal in certain cases when you +modify the work.) You may place additional permissions on material, added by you to a +covered work, for which you have or can give appropriate copyright permission. + +Notwithstanding any other provision of this License, for material you add to a +covered work, you may (if authorized by the copyright holders of that material) +supplement the terms of this License with terms: + +* **a)** Disclaiming warranty or limiting liability differently from the terms of +sections 15 and 16 of this License; or +* **b)** Requiring preservation of specified reasonable legal notices or author +attributions in that material or in the Appropriate Legal Notices displayed by works +containing it; or +* **c)** Prohibiting misrepresentation of the origin of that material, or requiring that +modified versions of such material be marked in reasonable ways as different from the +original version; or +* **d)** Limiting the use for publicity purposes of names of licensors or authors of the +material; or +* **e)** Declining to grant rights under trademark law for use of some trade names, +trademarks, or service marks; or +* **f)** Requiring indemnification of licensors and authors of that material by anyone +who conveys the material (or modified versions of it) with contractual assumptions of +liability to the recipient, for any liability that these contractual assumptions +directly impose on those licensors and authors. + +All other non-permissive additional terms are considered “further +restrictions” within the meaning of section 10. If the Program as you received +it, or any part of it, contains a notice stating that it is governed by this License +along with a term that is a further restriction, you may remove that term. If a +license document contains a further restriction but permits relicensing or conveying +under this License, you may add to a covered work material governed by the terms of +that license document, provided that the further restriction does not survive such +relicensing or conveying. + +If you add terms to a covered work in accord with this section, you must place, in +the relevant source files, a statement of the additional terms that apply to those +files, or a notice indicating where to find the applicable terms. + +Additional terms, permissive or non-permissive, may be stated in the form of a +separately written license, or stated as exceptions; the above requirements apply +either way. + +### 8. Termination + +You may not propagate or modify a covered work except as expressly provided under +this License. Any attempt otherwise to propagate or modify it is void, and will +automatically terminate your rights under this License (including any patent licenses +granted under the third paragraph of section 11). + +However, if you cease all violation of this License, then your license from a +particular copyright holder is reinstated **(a)** provisionally, unless and until the +copyright holder explicitly and finally terminates your license, and **(b)** permanently, +if the copyright holder fails to notify you of the violation by some reasonable means +prior to 60 days after the cessation. + +Moreover, your license from a particular copyright holder is reinstated permanently +if the copyright holder notifies you of the violation by some reasonable means, this +is the first time you have received notice of violation of this License (for any +work) from that copyright holder, and you cure the violation prior to 30 days after +your receipt of the notice. + +Termination of your rights under this section does not terminate the licenses of +parties who have received copies or rights from you under this License. If your +rights have been terminated and not permanently reinstated, you do not qualify to +receive new licenses for the same material under section 10. + +### 9. Acceptance Not Required for Having Copies + +You are not required to accept this License in order to receive or run a copy of the +Program. Ancillary propagation of a covered work occurring solely as a consequence of +using peer-to-peer transmission to receive a copy likewise does not require +acceptance. However, nothing other than this License grants you permission to +propagate or modify any covered work. These actions infringe copyright if you do not +accept this License. Therefore, by modifying or propagating a covered work, you +indicate your acceptance of this License to do so. + +### 10. Automatic Licensing of Downstream Recipients + +Each time you convey a covered work, the recipient automatically receives a license +from the original licensors, to run, modify and propagate that work, subject to this +License. You are not responsible for enforcing compliance by third parties with this +License. + +An “entity transaction” is a transaction transferring control of an +organization, or substantially all assets of one, or subdividing an organization, or +merging organizations. If propagation of a covered work results from an entity +transaction, each party to that transaction who receives a copy of the work also +receives whatever licenses to the work the party's predecessor in interest had or +could give under the previous paragraph, plus a right to possession of the +Corresponding Source of the work from the predecessor in interest, if the predecessor +has it or can get it with reasonable efforts. + +You may not impose any further restrictions on the exercise of the rights granted or +affirmed under this License. For example, you may not impose a license fee, royalty, +or other charge for exercise of rights granted under this License, and you may not +initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging +that any patent claim is infringed by making, using, selling, offering for sale, or +importing the Program or any portion of it. + +### 11. Patents + +A “contributor” is a copyright holder who authorizes use under this +License of the Program or a work on which the Program is based. The work thus +licensed is called the contributor's “contributor version”. + +A contributor's “essential patent claims” are all patent claims owned or +controlled by the contributor, whether already acquired or hereafter acquired, that +would be infringed by some manner, permitted by this License, of making, using, or +selling its contributor version, but do not include claims that would be infringed +only as a consequence of further modification of the contributor version. For +purposes of this definition, “control” includes the right to grant patent +sublicenses in a manner consistent with the requirements of this License. + +Each contributor grants you a non-exclusive, worldwide, royalty-free patent license +under the contributor's essential patent claims, to make, use, sell, offer for sale, +import and otherwise run, modify and propagate the contents of its contributor +version. + +In the following three paragraphs, a “patent license” is any express +agreement or commitment, however denominated, not to enforce a patent (such as an +express permission to practice a patent or covenant not to sue for patent +infringement). To “grant” such a patent license to a party means to make +such an agreement or commitment not to enforce a patent against the party. + +If you convey a covered work, knowingly relying on a patent license, and the +Corresponding Source of the work is not available for anyone to copy, free of charge +and under the terms of this License, through a publicly available network server or +other readily accessible means, then you must either **(1)** cause the Corresponding +Source to be so available, or **(2)** arrange to deprive yourself of the benefit of the +patent license for this particular work, or **(3)** arrange, in a manner consistent with +the requirements of this License, to extend the patent license to downstream +recipients. “Knowingly relying” means you have actual knowledge that, but +for the patent license, your conveying the covered work in a country, or your +recipient's use of the covered work in a country, would infringe one or more +identifiable patents in that country that you have reason to believe are valid. + +If, pursuant to or in connection with a single transaction or arrangement, you +convey, or propagate by procuring conveyance of, a covered work, and grant a patent +license to some of the parties receiving the covered work authorizing them to use, +propagate, modify or convey a specific copy of the covered work, then the patent +license you grant is automatically extended to all recipients of the covered work and +works based on it. + +A patent license is “discriminatory” if it does not include within the +scope of its coverage, prohibits the exercise of, or is conditioned on the +non-exercise of one or more of the rights that are specifically granted under this +License. You may not convey a covered work if you are a party to an arrangement with +a third party that is in the business of distributing software, under which you make +payment to the third party based on the extent of your activity of conveying the +work, and under which the third party grants, to any of the parties who would receive +the covered work from you, a discriminatory patent license **(a)** in connection with +copies of the covered work conveyed by you (or copies made from those copies), or **(b)** +primarily for and in connection with specific products or compilations that contain +the covered work, unless you entered into that arrangement, or that patent license +was granted, prior to 28 March 2007. + +Nothing in this License shall be construed as excluding or limiting any implied +license or other defenses to infringement that may otherwise be available to you +under applicable patent law. + +### 12. No Surrender of Others' Freedom + +If conditions are imposed on you (whether by court order, agreement or otherwise) +that contradict the conditions of this License, they do not excuse you from the +conditions of this License. If you cannot convey a covered work so as to satisfy +simultaneously your obligations under this License and any other pertinent +obligations, then as a consequence you may not convey it at all. For example, if you +agree to terms that obligate you to collect a royalty for further conveying from +those to whom you convey the Program, the only way you could satisfy both those terms +and this License would be to refrain entirely from conveying the Program. + +### 13. Use with the GNU Affero General Public License + +Notwithstanding any other provision of this License, you have permission to link or +combine any covered work with a work licensed under version 3 of the GNU Affero +General Public License into a single combined work, and to convey the resulting work. +The terms of this License will continue to apply to the part which is the covered +work, but the special requirements of the GNU Affero General Public License, section +13, concerning interaction through a network will apply to the combination as such. + +### 14. Revised Versions of this License + +The Free Software Foundation may publish revised and/or new versions of the GNU +General Public License from time to time. Such new versions will be similar in spirit +to the present version, but may differ in detail to address new problems or concerns. + +Each version is given a distinguishing version number. If the Program specifies that +a certain numbered version of the GNU General Public License “or any later +version” applies to it, you have the option of following the terms and +conditions either of that numbered version or of any later version published by the +Free Software Foundation. If the Program does not specify a version number of the GNU +General Public License, you may choose any version ever published by the Free +Software Foundation. + +If the Program specifies that a proxy can decide which future versions of the GNU +General Public License can be used, that proxy's public statement of acceptance of a +version permanently authorizes you to choose that version for the Program. + +Later license versions may give you additional or different permissions. However, no +additional obligations are imposed on any author or copyright holder as a result of +your choosing to follow a later version. + +### 15. Disclaimer of Warranty + +THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. +EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES +PROVIDE THE PROGRAM “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER +EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF +MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE +QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE +DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. + +### 16. Limitation of Liability + +IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY +COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS +PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, +INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE +PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE +OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE +WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE +POSSIBILITY OF SUCH DAMAGES. + +### 17. Interpretation of Sections 15 and 16 + +If the disclaimer of warranty and limitation of liability provided above cannot be +given local legal effect according to their terms, reviewing courts shall apply local +law that most closely approximates an absolute waiver of all civil liability in +connection with the Program, unless a warranty or assumption of liability accompanies +a copy of the Program in return for a fee. + +_END OF TERMS AND CONDITIONS_ + +## How to Apply These Terms to Your New Programs + +If you develop a new program, and you want it to be of the greatest possible use to +the public, the best way to achieve this is to make it free software which everyone +can redistribute and change under these terms. + +To do so, attach the following notices to the program. It is safest to attach them +to the start of each source file to most effectively state the exclusion of warranty; +and each file should have at least the “copyright” line and a pointer to +where the full notice is found. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper mail. + +If the program does terminal interaction, make it output a short notice like this +when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type 'show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type 'show c' for details. + +The hypothetical commands `show w` and `show c` should show the appropriate parts of +the General Public License. Of course, your program's commands might be different; +for a GUI interface, you would use an “about box”. + +You should also get your employer (if you work as a programmer) or school, if any, to +sign a “copyright disclaimer” for the program, if necessary. For more +information on this, and how to apply and follow the GNU GPL, see +<>. + +The GNU General Public License does not permit incorporating your program into +proprietary programs. If your program is a subroutine library, you may consider it +more useful to permit linking proprietary applications with the library. If this is +what you want to do, use the GNU Lesser General Public License instead of this +License. But first, please read +<>. diff --git a/README.md b/README.md new file mode 100644 index 0000000..5f50a98 --- /dev/null +++ b/README.md @@ -0,0 +1,81 @@ +# lethe README + +```lethe``` is a Python module for git-based snapshotting. + +```lethe``` is intended as a mechanism for creating commits outside +the standard git branching/tagging workflows. It is meant to enable +additional use-cases without disrupting the standard workflows. +Use cases include: + +- Short-lived: + - On-disk **undo log** + - **Syncing work-in-progress** between computers before it's ready +- Long-lived: + - **lab notebook**: Recording the code / configuration state that resulted in a given output + - **incremental backup**: Space-efficient time-based backups of a codebase + + +## Usage + +### Creating a commit from the command line +```bash +$ cd path/to/repo +$ lethe +122d058e375274a186c407f28602c3b14a2cab95 +``` +This effectively snapshots the current state of the repository (as would be seen by +```git add --all```) and creates a new commit (```122d058e375274a186c407f28602c3b14a2cab95```) +which points to it. The current branch and index are not changed. + +### Flags: +- ```-p my_parent_ref``` is used to provide "parent" refs which become the parents of the created commit. +If a parent ref is a symbolic ref, *both* the provided ref and the ref it points to are used as parents. +If not present, defaults to ```-p HEAD```. +- ```-t ref/lethe/my_target_ref``` is used to provide "target" refs which will be created/updated +to point to the created commit. +If not present, defaults to adding an entry of the form ```-t refs/lethe/my_branch``` for each +parent ref of the form ```refs/heads/my_branch```, and ```-t refs/lethe/my/refpath``` for non-head +refs of the form ```refs/my/refpath```. All provided parent refs *and* any dereferenced parent refs +are used to generate default target refs. +If any of the target refs already exist, the commits they point to become parents of the created commit. +- ```-m "my message"``` sets the commit message for the snapshot. By default, "snapshot " is used. +- ```-r path/to/repo``` can be provided to specify a repository outside of the current working directory. + +```bash +$ cd path/to/repo +$ git branch +* master +$ lethe +``` +is equivalent to +```bash +lethe -r path/to/repo -p HEAD +``` +or +```bash +lethe -r path/to/repo -p HEAD -p refs/heads/master -t refs/lethe/HEAD -t refs/lethe/master +``` + +### Creating a commit programmatically +```python +import lethe +REPO = '/path/to/repo' + +commit_sha = lethe.snap(cwd=REPO) +tree_sha = lethe.get_tree(commit_sha, cwd=REPO) + +print('Created new commit with hash ' + commit_sha + ' aka refs/lethe/HEAD') +print('Code (tree) state is ' + tree_sha) +``` + + +## Installation + +Requirements: +* python 3 (written and tested with 3.6) +* git (accessible on the system ```PATH```) + +Install with pip: +```bash +pip install lethe +``` diff --git a/lethe.py b/lethe.py new file mode 100755 index 0000000..71e700c --- /dev/null +++ b/lethe.py @@ -0,0 +1,220 @@ +#!/usr/bin/env python3 +""" +Git snapshotting tool +""" + +import subprocess +import tempfile +import datetime +import argparse +from itertools import chain +from typing import List +import sys + + +__author__ = 'Jan Petykeiwicz' +version = 0.5 + + +def _run(command: str or List[str], **kwargs): + """ + Wrapper for subprocess.run(): + - Accepts args as either a list of strings or space-delimited string + - Captures and returns stdouti + """ + if isinstance(command, str): + args = command.split() + else: + args = command +# print('run', ' '.join(args)) + result = subprocess.run(args, stdout=subprocess.PIPE, **kwargs) + return result.stdout.decode().strip() + + +def get_root(cwd: str=None) -> str: + """ + Get the root directory of a git repository + """ + root = _run('git rev-parse --show-toplevel', cwd=cwd) + if not root: + raise Exception('Must be run from inside git repository!') + return root + + +def get_obj(ref: str, cwd: str=None) -> str: + """ + Transform a ref into its corresponding hash using git-rev-parse + """ + sha = _run('git rev-parse --quiet --verify'.split() + [ref], cwd=cwd) + return sha + + +def get_commit(ref: str, cwd: str=None) -> str: + """ + Transform a ref to a commit into its corresponding hash using git-rev-parse + """ + return get_obj(ref, cwd=cwd) + + +def get_tree(ref: str, cwd: str=None) -> str: + """ + Take a ref to a commit, and return the hash of the tree it points to + """ + return get_obj(ref + ':', cwd=cwd) + + +def commit_tree(tree: str, + parents: List[str], + message: str = None, + cwd: str = None, + ) -> str: + """ + Create a commit pointing to the given tree, with the specified parent commits and message. + Return the hash of the created commit. + """ + if message is None: + message = 'snapshot ' + str(datetime.datetime.now()) + + pargs = list(chain.from_iterable(('-p', p) for p in parents)) + commit = _run(['git', 'commit-tree', tree, *pargs, '-m', message], cwd=cwd) # Create commit + return commit + + +def update_ref(target_ref: str, + target_commit: str, + old_commit: str = None, + message: str = 'new snapshot', + cwd: str = None, + ) -> str: + """ + Update target_ref to point to target_commit, optionally verifying that + it points old_commit before the update. + Returns the resulting ref. + """ + cmd = ['git', 'update-ref', '-m', message, target_ref, target_commit] + if old_commit is not None: + cmd.append(old_commit) + result_ref = _run(cmd, cwd=cwd) + return result_ref + + +def deref_symref(ref: str, cwd: str=None) -> str: + """ + Dereference a symbolic ref + """ + return _run(['git', 'symbolic-ref', '--quiet', ref], cwd=cwd) + + +def find_merge_base(commits: List[str], cwd: str=None) -> str: + """ + Find the "best common ancestor" commit. + """ + base = _run(['git', 'merge-base', *commits], cwd=cwd) + return base + + +def snap_tree(cwd: str=None) -> str: + """ + Create a new tree, consisting of all non-ignored files in the repository. + Return the hash of the tree. + """ + with tempfile.TemporaryDirectory() as tmp_dir: + env = {'GIT_INDEX_FILE': tmp_dir + '/git-snapshot-index'} + + # TODO: Mayve need cwd=get_root(cwd) here? + _run('git add --all', env=env, cwd=cwd) + tree = _run('git write-tree', env=env, cwd=cwd) + return tree + + +def snap_ref(parent_refs: List[str], + target_refs: List[str], + message: str = None, + cwd: str = None, + ) -> str: + """ + is used as the commit message. + """ + new_tree = snap_tree(cwd=cwd) + parent_commits = [c for c in [get_commit(p, cwd=cwd) for p in parent_refs] if c] + old_commits = [get_commit(t, cwd=cwd) for t in target_refs] + + extant_old_commits = list(set(c for c in old_commits if c)) + new_parents = list(set(p for p in parent_commits + if p != find_merge_base([p] + extant_old_commits, cwd=cwd))) + +# if not new_parents: +# tree_unchanged = all(new_tree == get_tree(c, cwd=cwd) for c in old_commits) +# if tree_unchanged: +# return new_tree + + commit = commit_tree(new_tree, extant_old_commits + new_parents, message, cwd=cwd) + + for target_ref, old_commit in zip(target_refs, old_commits): + # update ref to point to commit, or create new ref + old_or_none = old_commit if old_commit else None + update_ref(target_ref, commit, old_commit=old_or_none, cwd=cwd) + + return commit + + + +def snap(parent_refs: List[str] = None, + target_refs: List[str] = None, + message: str = None, + cwd: str = None, + ) -> str: + """ + Create a new commit of all non-ignored files in the repository. + + default to ['HEAD']. + If there are any symbolic refs in , the refs + they point to are added to . + + All commits pointed to by existing and , + become parents of the newly created commit. + + are created/updated to point the commit. + Default is + 'refs/lethe/head_name' for each parent ref of the form + 'refs/heads/head_name', and + 'refs/lethe/path/to/ref' for each parent ref of the form + 'refs/path/to/ref'. + is used as the commit message. + """ + if parent_refs is None: + parent_refs = ['HEAD'] + + parent_refs += [r for r in [deref_symref(s, cwd=cwd) for s in parent_refs] if r] + + if target_refs is None: + target_refs = [] + for p in parent_refs: + if p.startswith('refs/'): + p = p[len('refs/'):] + + target_refs.append('refs/lethe/' + p) + + commit = snap_ref(parent_refs, target_refs, message=message, cwd=cwd) + return commit + + +def main() -> int: + parser = argparse.ArgumentParser() + parser.add_argument('--parent', '-p', action='append', default=['HEAD']) + parser.add_argument('--target', '-t', action='append') + parser.add_argument('--message', '-m') + parser.add_argument('--repo', '-r') + + args = parser.parse_args() + + print(snap(parent_refs=args.parent, + target_refs=args.target, + message=args.message, + cwd=args.repo)) + return 0 + + +if __name__ == '__main__': + main() + diff --git a/setup.py b/setup.py new file mode 100644 index 0000000..4f65088 --- /dev/null +++ b/setup.py @@ -0,0 +1,48 @@ +#!/usr/bin/env python3 + +from setuptools import setup +import lethe + +with open('README.md', 'r') as f: + long_description = f.read() + +setup(name='lethe', + version=lethe.version, + description='Git-based snapshotting', + long_description=long_description, + long_description_content_type='text/markdown', + author='Jan Petykiewicz', + author_email='anewusername@gmail.com', + py_modules=['lethe'], + entry_points={ + 'console_scripts': [ + 'lethe=lethe:main', + ], + }, + install_requires=[ + 'typing', + ], + url='https://mpxd.net/code/jan/lethe', + keywords=[ + 'git', + 'snapshot', + 'commit', + 'refs', + 'backup', + 'undo', + 'log', + 'lab notebook', + 'traceability', + ], + classifiers=[ + 'Programming Language :: Python', + 'Programming Language :: Python :: 3', + 'Development Status :: 4 - Beta', + 'Environment :: Other Environment', + 'Intended Audience :: Developers', + 'Intended Audience :: Science/Research', + 'License :: OSI Approved :: GNU General Public License v3 (GPLv3)', + 'Topic :: Software Development :: Version Control :: Git', + 'Topic :: Utilities', + ], + )