ee46e2f9b7
Make a version-less RHEL element to handle both '7' and '8' DIB_RELEASE. The element usage should align with other elements which operate in the same way such as the Fedora element. Additionally, this patch adds support for RHEL8 that operates with Python 3. As of now, users of diskimage-builder will still be able to use the 'rhel7' element, or migrate to 'rhel' and specify their respective DIB_RELEASE value. * mount the xfs file-system for extraction as read-only. vaguely based on explaination in [1] and the fact we only read the image data into a tar, so can ignore this. XFS (dm-1): Superblock has unknown read-only compatible features (0x4) enabled. * Use the redhat system python as the dib-python version. dib was ahead of it's time making an abstracted python interpreter for system work ;) the system python should work for running the various dib element scripts. [1] https://unix.stackexchange.com/questions/247550/unmountable-xfs-filesystem Redhat-Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1700253 Co-Authored-By: Ian Wienand <iwienand@redhat.com> Change-Id: I90540675c70bb475d9db2ae24f81c648a31f3f95 |
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install.d/pip-and-virtualenv-source-install | ||
post-install.d | ||
test-elements | ||
element-deps | ||
package-installs.yaml | ||
pkg-map | ||
README.rst | ||
source-repository-pip-and-virtualenv |
================== pip-and-virtualenv ================== This element installs pip and virtualenv in the image. .. note:: This element setups and Python 2 and Python 3 environment. This means it will bring in python2 packages, so isn't appropriate if you want a python3 only environment. Package install =============== If the package installtype is used then these programs are installed from distribution packages. In this case, ``pip`` and ``virtualenv`` will be installed *only* for the python version identified by ``dib-python`` (i.e. the default python for the platform). Distribution packages have worked out name-spacing such that only python2 or python3 owns common scripts like ``/usr/bin/pip`` (on most platforms, ``pip`` refers to python2 pip, and ``pip3`` refers to python3 pip, although some may choose the reverse). To install pip and virtualenv from package:: export DIB_INSTALLTYPE_pip_and_virtualenv=package Source install ============== Source install is the default. If the source installtype is used, ``pip`` and ``virtualenv`` are installed from the latest upstream releases. Source installs from these tools are not name-spaced. It is inconsistent across platforms if the first or last install gets to own common scripts like ``/usr/bin/pip`` and ``virtualenv``. To avoid inconsistency, we firstly install the packaged python 2 **and** 3 versions of ``pip`` and ``virtualenv``. This prevents a later install of these distribution packages conflicting with the source install. We then overwrite ``pip`` and ``virtualenv`` via ``get-pip.py`` and ``pip`` respectively. The system will be left in the following state: * ``/usr/bin/pip`` : python2 pip * ``/usr/bin/pip2`` : python2 pip (same as prior) * ``/usr/bin/pip3`` : python3 pip * ``/usr/bin/virtualenv`` : python2 virtualenv (note python3 ``virtualenv`` script is *not* installed, see below) Source install is supported on limited platforms. See the code, but this includes Ubuntu and RedHat platforms. Using the tools =============== Due to the essentially unsolvable problem of "who owns the script", it is recommended to *not* call ``pip`` or ``virtualenv`` directly. You can directly call them with the ``-m`` argument to the python interpreter you wish to install with. For example, to create a python3 environment do:: # python3 -m virtualenv myenv # myenv/bin/pip install mytool To install a python2 tool from pip:: # python2 -m pip install mytool In this way, you can always know which interpreter is being used (and affected by) the call. Ordering ======== Any element that uses these commands must be designated as 05-* or higher to ensure that they are first installed.