Run pylint with pytest and have configurable rule types (i.e. Convention, Warn, and Error) fail the build. You can also specify a pylintrc file.
py.test --pylint
would be the most simple usage and would run pylint for all error messages.
py.test --pylint --pylint-rcfile=/my/pyrc --pylint-error-types=EF
This would use the pylintrc file at /my/pyrc and only error on pylint Errors and Failures.
This code is heavily based on pytest-flakes