Avoiding installation of build dependencies

Hey there,

Is there a way to avoid the installation of implicit dependencies, as in this case:

$ snapcraft
Installing build dependencies: golang-1.6-go golang-1.6-race-detector-runtime
golang-1.6-src golang-go golang-race-detector-runtime golang-src

I don’t need those dependencies on my system, and almost every other developer won’t either because that’s a pretty old version of Go. Somewhat ironically, these developers can install a newer Go version via snaps, so instead of hardcoding the deb install, the system should be introspected to check if that’s indeed necessary.

As an aside, when that does run and an error happens, a pretty ugly message is dumped into the user’s terminal due to unhandled exceptions:

Unpacking golang-go (2:1.6-1ubuntu4) ...
dpkg: error processing archive /var/cache/apt/archives/golang-go_2%3a1.6-1ubuntu4_amd64.deb (--unpack):
 trying to overwrite '/usr/bin/gofmt', which is also in package go:i386 1.4-godeb1
Selecting previously unselected package golang-1.6-race-detector-runtime.
Preparing to unpack .../golang-1.6-race-detector-runtime_0.0+svn252922-0ubuntu1_amd64.deb ...
Unpacking golang-1.6-race-detector-runtime (0.0+svn252922-0ubuntu1) ...
Selecting previously unselected package golang-race-detector-runtime.
Preparing to unpack .../golang-race-detector-runtime_2%3a1.6-1ubuntu4_amd64.deb ...
Unpacking golang-race-detector-runtime (2:1.6-1ubuntu4) ...
Processing triggers for man-db (2.7.5-1) ...
Errors were encountered while processing:
E: Sub-process /usr/bin/dpkg returned an error code (1)
Traceback (most recent call last):
  File "/usr/bin/snapcraft", line 9, in <module>
    load_entry_point('snapcraft==2.35', 'console_scripts', 'snapcraft')()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 542, in load_entry_point
    return get_distribution(dist).load_entry_point(group, name)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2569, in load_entry_point
    return ep.load()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2229, in load
    return self.resolve()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2235, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
  File "/usr/lib/python3/dist-packages/snapcraft/cli/__main__.py", line 19, in <module>
  File "/usr/lib/python3/dist-packages/click/core.py", line 716, in __call__
    return self.main(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/click/core.py", line 696, in main
    rv = self.invoke(ctx)
  File "/usr/lib/python3/dist-packages/click/core.py", line 1037, in invoke
    return Command.invoke(self, ctx)
  File "/usr/lib/python3/dist-packages/click/core.py", line 889, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/lib/python3/dist-packages/click/core.py", line 534, in invoke
    return callback(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/click/decorators.py", line 17, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/usr/lib/python3/dist-packages/snapcraft/cli/__init__.py", line 124, in run
  File "/usr/lib/python3/dist-packages/click/core.py", line 552, in forward
    return self.invoke(cmd, **kwargs)
  File "/usr/lib/python3/dist-packages/click/core.py", line 534, in invoke
    return callback(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/snapcraft/cli/lifecycle.py", line 140, in snap
    project_options, directory=directory, output=output)
  File "/usr/lib/python3/dist-packages/snapcraft/internal/lifecycle/_packer.py", line 45, in snap
    execute('prime', project_options)
  File "/usr/lib/python3/dist-packages/snapcraft/internal/lifecycle/_runner.py", line 63, in execute
  File "/usr/lib/python3/dist-packages/snapcraft/internal/repo/_deb.py", line 205, in install_build_packages
    [package[0] for package in new_packages])
  File "/usr/lib/python3/dist-packages/snapcraft/internal/repo/_deb.py", line 243, in _install_new_build_packages
    subprocess.check_call(apt_command + package_names, env=env)
  File "/usr/lib/python3.5/subprocess.py", line 581, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['sudo', 'apt-get', '--no-install-recommends', '-y', '-o', 'Dpkg::Progress-Fanc
y=1', 'install', 'golang-1.6-go', 'golang-1.6-race-detector-runtime', 'golang-1.6-src', 'golang-go', 'golang-race-detec
tor-runtime', 'golang-src']' returned non-zero exit status 100
1 Like

you probably want to use “snapcraft cleanbuild” to keep your host clean (and also to make sure you get 16.04 dependencies in case your desktop runs something newer )…

beyond this, “sudo apt autoremove” will remove the deps afterwards.

i doubt there is any way to actually avoid installation build deps if you use snapcraft natively on the machine.

Yes, there’s a simple way. We fix it. :slight_smile:

@sergiusens Do you have a position on this issue?

We are aware of this problem and the fix for it is planned.