Argthtjtr

I'm interested in building a small container image which has pip-installed packages, but unfortunately, installing python3-pip via apt-get pulls in a lot of dependencies (348MB) into an otherwise very small minimal ubuntu image (I'm currently using the <50MB ubuntu:xenial images from dockerhub):

root@dce44a07a6a5:/home# apt-get install python3-pip

Reading package lists... Done

Building dependency tree       

Reading state information... Done

The following additional packages will be installed:

  binutils binutils-common binutils-x86-64-linux-gnu build-essential cpp cpp-7 dh-python dirmngr dpkg-dev fakeroot g++ g++-7 gcc gcc-7 gcc-7-base gir1.2-glib-2.0 gnupg gnupg-l10n

  gnupg-utils gpg gpg-agent gpg-wks-client gpg-wks-server gpgconf gpgsm libalgorithm-diff-perl libalgorithm-diff-xs-perl libalgorithm-merge-perl libasan4 libassuan0 libatomic1 libbinutils

  libc-dev-bin libc6-dev libcc1-0 libcilkrts5 libdpkg-perl libexpat1-dev libfakeroot libfile-fcntllock-perl libgcc-7-dev libgdbm-compat4 libgdbm5 libgirepository-1.0-1 libglib2.0-0

  libglib2.0-data libgomp1 libicu60 libisl19 libitm1 libksba8 liblocale-gettext-perl liblsan0 libmpc3 libmpfr6 libmpx2 libnpth0 libperl5.26 libpython3-dev libpython3.6 libpython3.6-dev

  libquadmath0 libstdc++-7-dev libtsan0 libubsan0 libxml2 linux-libc-dev make manpages manpages-dev netbase patch perl perl-modules-5.26 pinentry-curses python-pip-whl python3-asn1crypto

  python3-cffi-backend python3-crypto python3-cryptography python3-dbus python3-dev python3-distutils python3-gi python3-idna python3-keyring python3-keyrings.alt python3-lib2to3

  python3-pkg-resources python3-secretstorage python3-setuptools python3-six python3-wheel python3-xdg python3.6-dev shared-mime-info xdg-user-dirs

Suggested packages:

  binutils-doc cpp-doc gcc-7-locales dbus-user-session libpam-systemd pinentry-gnome3 tor debian-keyring g++-multilib g++-7-multilib gcc-7-doc libstdc++6-7-dbg gcc-multilib autoconf

  automake libtool flex bison gdb gcc-doc gcc-7-multilib libgcc1-dbg libgomp1-dbg libitm1-dbg libatomic1-dbg libasan4-dbg liblsan0-dbg libtsan0-dbg libubsan0-dbg libcilkrts5-dbg

  libmpx2-dbg libquadmath0-dbg parcimonie xloadimage scdaemon glibc-doc git bzr gdbm-l10n libstdc++-7-doc make-doc man-browser ed diffutils-doc perl-doc libterm-readline-gnu-perl

  | libterm-readline-perl-perl pinentry-doc python-crypto-doc python-cryptography-doc python3-cryptography-vectors python-dbus-doc python3-dbus-dbg gnome-keyring libkf5wallet-bin

  gir1.2-gnomekeyring-1.0 python-secretstorage-doc python-setuptools-doc

The following NEW packages will be installed:

  binutils binutils-common binutils-x86-64-linux-gnu build-essential cpp cpp-7 dh-python dirmngr dpkg-dev fakeroot g++ g++-7 gcc gcc-7 gcc-7-base gir1.2-glib-2.0 gnupg gnupg-l10n

  gnupg-utils gpg gpg-agent gpg-wks-client gpg-wks-server gpgconf gpgsm libalgorithm-diff-perl libalgorithm-diff-xs-perl libalgorithm-merge-perl libasan4 libassuan0 libatomic1 libbinutils

  libc-dev-bin libc6-dev libcc1-0 libcilkrts5 libdpkg-perl libexpat1-dev libfakeroot libfile-fcntllock-perl libgcc-7-dev libgdbm-compat4 libgdbm5 libgirepository-1.0-1 libglib2.0-0

  libglib2.0-data libgomp1 libicu60 libisl19 libitm1 libksba8 liblocale-gettext-perl liblsan0 libmpc3 libmpfr6 libmpx2 libnpth0 libperl5.26 libpython3-dev libpython3.6 libpython3.6-dev

  libquadmath0 libstdc++-7-dev libtsan0 libubsan0 libxml2 linux-libc-dev make manpages manpages-dev netbase patch perl perl-modules-5.26 pinentry-curses python-pip-whl python3-asn1crypto

  python3-cffi-backend python3-crypto python3-cryptography python3-dbus python3-dev python3-distutils python3-gi python3-idna python3-keyring python3-keyrings.alt python3-lib2to3

  python3-pip python3-pkg-resources python3-secretstorage python3-setuptools python3-six python3-wheel python3-xdg python3.6-dev shared-mime-info xdg-user-dirs

0 upgraded, 98 newly installed, 0 to remove and 2 not upgraded.

Need to get 108 MB of archives.

After this operation, 348 MB of additional disk space will be used.

A lot of this is for compilation of c modules. I'm wondering if there is an alternative to using pip for installing python modules when building containers.

Perhaps there is a programmatic way to install pip, install dependencies, and then uninstall pip cleanly in the same docker layer?

i.e. (paraphrasing):

RUN  install_pip && pip install mymod && uninstall_pip

If you have to stick to ubuntu, use apt-get install --no-install-recommends python3-pip. It only takes 33.9 MB, 10 times less. The final imaged is 146M.

If you are able to use debian, use python:3.6-slim as base image (138M), to push it further, use python:alpine(78.2M).

You can remove pip with python3 -m pip uninstall pip setuptools for the last 2 cases, but due to the layer overhead, it actually makes it bigger.