Getting error ImportMismatchError while running py.test
PythonDockerPytestPython Problem Overview
When I am running tests locally its working fine, but after creating the docker and running inside the container I am getting below error.
/usr/local/lib/python3.5/site-packages/_pytest/config.py:325: in _getconftestmodules
return self._path2confmods[path]
E KeyError: local('/apis/db/tests')
During handling of the above exception, another exception occurred:
/usr/local/lib/python3.5/site-packages/_pytest/config.py:356: in _importconftest
return self._conftestpath2mod[conftestpath]
E KeyError: local('/apis/db/tests/conftest.py')
During handling of the above exception, another exception occurred:
/usr/local/lib/python3.5/site-packages/_pytest/config.py:362: in _importconftest
mod = conftestpath.pyimport()
/usr/local/lib/python3.5/site-packages/py/_path/local.py:680: in pyimport
raise self.ImportMismatchError(modname, modfile, self)
_pytest.config.ConftestImportFailure: ImportMismatchError('conftest', '/projects/my_project/db/tests/conftest.py', local('/apis/db/tests/conftest.py'))
/apis - its the WORKDIR in Dockerfile.
Python Solutions
Solution 1 - Python
I have fixed it by removing all _pycache_ pkg under test/ directory, the issue was when I was creating docker image its picking all my _pycache_ and *.pyc files too, at the time when test are running its using my local machine path instead of the path in docker container.
Conclusion: Clear your *.pyc and _pycache_ files before creating a docker image.
Solution 2 - Python
You can use the .dockerignore file to exclude all __pycache__ folders from being sent to the docker image context:
.dockerignore file, excludes __pycache__ folders and *.pyc files from all sub/folders:
**/__pycache__
**/*.pyc
Solution 3 - Python
I am using Python 3.6. In my case, I was getting ImportMismatchError in modules with the same name under different packages, e.g., A/B/main.py and C/D/main.py. Python 3 does not require __init__.py file in source folders, but adding __init__.py under A/B and C/D solved the issue.
Solution 4 - Python
Delete all the .pyc files. You can do this by
find . -name \*.pyc -delete
Solution 5 - Python
You can set environment variable PY_IGNORE_IMPORTMISMATCH=1 to skip this errros. It should be fine in simple cases like running tests inside and outside docker container.
Solution 6 - Python
Found __pycache__ files in coverage/fullcoverage/ which are hidden in jupyter notebook etc.
simply navigate to the folder and use rm -r __pyache__/ . This will take care of your pytest.