Replace pysha3 with pycryptodomex

[drizzt]

pysha3 is not maintained anymore and it doesn't build correctly with Python 3.11 so replace it with pycryptodomex that is still maintained and working correctly with new python versions

[stefanor]

hashlib has had SHA3 built-in since 3.6, why not just stick to that?

[petertodd]

OpenTimestamps supported the pre-release version of SHA3 that Ethereum uses, not official SHA3. There's so few ETH timestamps out there that I don't know if we really need to keep this support.

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On October 29, 2022 1:48:02 PM GMT+02:00, Stefano Rivera ***@***.***> wrote: hashlib has had SHA3 built-in since 3.6, why not just stick to that? -- Reply to this email directly or view it on GitHub: #47 (comment) You are receiving this because you are subscribed to this thread. Message ID: ***@***.***>

[dhimmel]

A bit more on the pysha3 dependency breaking in Python 3.11. From a CI run:

  × Running setup.py install for pysha3 did not run successfully.
      In file included from Modules/_sha3/sha3module.c:20:
      Modules/_sha3/backport.inc:78:10: fatal error: pystrhex.h: No such file or directory
         78 | #include "pystrhex.h"
            |          ^~~~~~~~~~~~
      compilation terminated.
      error: command '/usr/bin/gcc' failed with exit code 1
      [end of output]

From the Python 3.11 release notes:

Remove the pystrhex.h header file. It only contains private functions. C extensions should only include the main <Python.h> header file. (Contributed by Victor Stinner in bpo-45434.)

Am seeing pysha3 requirement in a few places:

https://github.com/opentimestamps/opentimestamps-server/blob/ac67218c3d45a93519bea0ec151b1e3629f87bd5/requirements.txt#L4

python-opentimestamps/requirements.txt

Line 3 in 5ac3b06

pysha3>=1.0.2

python-opentimestamps/setup.py

Lines 72 to 73 in 5ac3b06

	install_requires=['python-bitcoinlib>=0.9.0,<0.12.0',
	'pysha3>=1.0.2'],

There's so few ETH timestamps out there that I don't know if we really need to keep this support.

Could always make it an extra dependency that is not installed by default. And ETH timestamps would fail if not installed. OOC would this prevent validating existing ETH timestamps or just creating new ones?

[dhimmel]

Also noting from https://github.com/tiran/pysha3:

The pysha3 package has reached its end of life and is no longer supported.

[dhimmel]

More sideline encouragement for Python 3.11 compatibility whether through pycryptodomex or through removed ETH timestamp support.

[petertodd]

Thanks, I went ahead and merged this. Will do a new release shortly.