pip error: Could not find an activated virtualenv (required)

Running pip commands encounter Could not find an activated virtualenv (required) error. Some of the options to get around this error are discussed in this blog post.

eg.,

# pip uninstall oci
ERROR: Could not find an activated virtualenv (required).

Try running the failed command by setting PIP_REQUIRE_VIRTUALENV to false. If the command succeeds and you don't want to encounter the same error in future, consider saving this environment variable in user's profile.

# PIP_REQUIRE_VIRTUALENV=false pip uninstall oci
Found existing installation: oci 2.18.0
Uninstalling oci-2.18.0:
  Would remove:
    /usr/lib/python2.7/site-packages/oci-2.18.0.dist-info/*
    /usr/lib/python2.7/site-packages/oci/*
Proceed (y/n)?

Another option is to run pip in isolated mode that ignores environment variables and user configuration.

# pip --isolated uninstall oci

Be aware that running in isolated mode won't ignore global configuration but only the user configuration. Therefore if there is a global configuration (say /etc/pip.conf) with a setting that forces virtual environment, --isolated option won't help.

eg.,

# pip --isolated uninstall oci
ERROR: Could not find an activated virtualenv (required).

In this case, examine global configuration by listing active configuration.

# pip config list
global.require-virtualenv='true'

Find out where the active configuration was loaded from by running pip with --verbose or -v (verbose) option.

# pip config list -v
For variant 'global', will try loading '/etc/xdg/pip/pip.conf'
For variant 'global', will try loading '/etc/pip.conf'
For variant 'user', will try loading '/root/.pip/pip.conf'
For variant 'user', will try loading '/root/.config/pip/pip.conf'
For variant 'site', will try loading '/usr/pip.conf'
global.require-virtualenv='true'

Finally edit global configuration to turn off the virtual environment requirement, and run the target pip command.

If editing the global configuration is not a viable option, consider ignoring global configuration tentatively while running target pip command(s).

eg.,

# PIP_CONFIG_FILE=/dev/null pip uninstall oci
Found existing installation: oci 2.18.0
Uninstalling oci-2.18.0:
  Would remove:
    /usr/lib/python2.7/site-packages/oci-2.18.0.dist-info/*
    /usr/lib/python2.7/site-packages/oci/*
Proceed (y/n)?