I am trying to have a fixed version of Python 3 inside a snap, and was bitten by the problem at “Classic snaps failing on Ubuntu 17.10”.
So I upgraded to the latest snapcraft with snap install snapcraft --beta --classic, and tried building it with:
apps:
python3:
command: bin/python3.6
parts:
python3:
source: https://www.python.org/ftp/python/3.6.3/Python-3.6.3.tar.xz
plugin: autotools
configflags:
- --prefix=/usr
build-packages:
- libssl-dev
prime:
- -usr/include
It started complaining that it couldn’t find prime/bin/python3.6, so I removed the --prefix=/usr bit.
Then it started complaining that it couldn’t find libc6:
/snap/my-snap-name/x1/bin/python3.6: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.25' not found (required by /snap/my-snap-name/x1/bin/python3.6)
So I added stage-packages: [libc6].
But now I’m stuck with a apt.cache.FetchFailedException:
$ snapcraft
Preparing to pull python3
Fetched 0 B in 0s (0 B/s)
Traceback (most recent call last):
File "/snap/snapcraft/876/lib/python3.6/site-packages/apt/cache.py", line 452, in update
pulse_interval)
SystemError: E:Method http has died unexpectedly!, E:Sub-process http received a segmentation fault.
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/snap/snapcraft/876/bin/snapcraft", line 11, in <module>
load_entry_point('snapcraft==2.36', 'console_scripts', 'snapcraft')()
File "/snap/snapcraft/876/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 565, in load_entry_point
return get_distribution(dist).load_entry_point(group, name)
File "/snap/snapcraft/876/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 2631, in load_entry_point
return ep.load()
File "/snap/snapcraft/876/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 2291, in load
return self.resolve()
File "/snap/snapcraft/876/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 2297, in resolve
module = __import__(self.module_name, fromlist=['__name__'], level=0)
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/cli/__main__.py", line 19, in <module>
run(prog_name='snapcraft')
File "/snap/snapcraft/876/lib/python3.6/site-packages/click/core.py", line 722, in __call__
return self.main(*args, **kwargs)
File "/snap/snapcraft/876/lib/python3.6/site-packages/click/core.py", line 697, in main
rv = self.invoke(ctx)
File "/snap/snapcraft/876/lib/python3.6/site-packages/click/core.py", line 1043, in invoke
return Command.invoke(self, ctx)
File "/snap/snapcraft/876/lib/python3.6/site-packages/click/core.py", line 895, in invoke
return ctx.invoke(self.callback, **ctx.params)
File "/snap/snapcraft/876/lib/python3.6/site-packages/click/core.py", line 535, in invoke
return callback(*args, **kwargs)
File "/snap/snapcraft/876/lib/python3.6/site-packages/click/decorators.py", line 17, in new_func
return f(get_current_context(), *args, **kwargs)
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/cli/__init__.py", line 124, in run
ctx.forward(lifecyclecli.commands['snap'])
File "/snap/snapcraft/876/lib/python3.6/site-packages/click/core.py", line 553, in forward
return self.invoke(cmd, **kwargs)
File "/snap/snapcraft/876/lib/python3.6/site-packages/click/core.py", line 535, in invoke
return callback(*args, **kwargs)
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/cli/lifecycle.py", line 140, in snap
project_options, directory=directory, output=output)
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/internal/lifecycle/_packer.py", line 45, in snap
execute('prime', project_options)
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/internal/lifecycle/_runner.py", line 80, in execute
_Executor(config, project_options).run(step, part_names)
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/internal/lifecycle/_runner.py", line 175, in run
self._run_step(step, part, part_names)
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/internal/lifecycle/_runner.py", line 205, in _run_step
getattr(part, 'prepare_{}'.format(step))()
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/internal/pluginhandler/__init__.py", line 241, in prepare_pull
self._fetch_stage_packages()
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/internal/pluginhandler/__init__.py", line 227, in _fetch_stage_packages
stage_packages)
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/internal/repo/_deb.py", line 294,in get
with self._apt.archive(self._cache.base_dir) as apt_cache:
File "/snap/snapcraft/876/usr/lib/python3.6/contextlib.py", line 82, in __enter__
return next(self.gen)
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/internal/repo/_deb.py", line 142,in archive
raise e
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/internal/repo/_deb.py", line 133,in archive
apt_cache = self._setup_apt(cache_dir)
File "/snap/snapcraft/876/lib/python3.6/site-packages/snapcraft/internal/repo/_deb.py", line 126,in _setup_apt
sources_list=sources_list_file)
File "/snap/snapcraft/876/lib/python3.6/site-packages/apt/cache.py", line 454, in update
raise FetchFailedException(e)
apt.cache.FetchFailedException: E:Method http has died unexpectedly!, E:Sub-process http received asegmentation fault.
BTW, before I go any further (since snap might not be ready yet for production), my intention is packaging a set of Python scripts that I want to make sure I can run in 10 years (they don’t need security, etc.). So I wanted not only to have a Virtualenv, but also a fixed version of Python 3 and imagemagick. I have some bash scripts in other project in the same situation too. Do you think snap is a good idea for that? I have already this setup with Docker, but some disadvantages are that 1) docker run needs root, and these are common user scripts that run without a TTY - I don’t want to allow docker in sudoers, 2) containers take a few seconds to startup (I need them fast), 3) Docker’s filesystem is not accessible as Snap’s is, so I can’t use its virtualenv with a code editor.