13.2.6. Testing framework

NextGIS Web testing framework is based on pytest library with some additions (predefined fixtures, marks) and conventions. It supports unit and functional tests. File layout

Each NextGIS Web component have its own set of tests located inside test directory. Consider the directory structure on the example for package package and component component.

πŸ—                               # Repository root directory
β”œβ”€β”€ πŸ— package                   # Package source root
β”‚   β”œβ”€β”€ πŸ— component             # Component root directory
β”‚   β”‚   β”œβ”€β”€ πŸ— test              # Test root directory
β”‚   β”‚   β”‚   β”œβ”€β”€ πŸ—€ data          # Test data directory
β”‚   β”‚   β”‚   β”œβ”€β”€ πŸ—Ž __init__.py   # Dummy __init__ module
β”‚   β”‚   β”‚   └── πŸ—Ž test_*.py     # Test module files
β”‚   β”‚   └── πŸ—Ž __init__.py       # And other component files
β”‚   └── πŸ—Ž __init__.py           # Package files and other components
└── πŸ—Ž setup.py                  # Setuptools configuration file Unit tests

Unit tests are designed for testing modules and usually don’t require additional configuration. Refer pytest documentation and Writing tests section.

# package/component/test/test_unit.py
from .. import some_function

def test_some_function():
    assert some_function(1) == 0 Functional tests

Functional tests operate on data, and NextGIS Web must be configured and have the database initialized via nextgisweb initialize_db. Some tests modify data, so don’t run these tests in a production environment. Server-side

Server-side tests are executed in the same context as other NextGIS Web console scripts. The environment can be loaded with ngw_env fixture, which initializes components and the environment.

# package/component/test/test_env.py

def test_component(ngw_env):

Tests inside a transaction can be performed using ngw_txn fixture. It begins a new transaction and rollbacks it at exit, flushing changes to the database before that.

# package/component/test/test_txn.py
from ..model import SomeModel

def test_transaction(ngw_txn):
    SomeModel(field='value').persist()  # Dummy record insert Web application

For testing via HTTP requests fixture ngw_webtest_app can be used. It’s represents WebTest TestApp instance which can be used for doing requests.

# package/component/test/test_webapp.py

def test_api_method(ngw_webtest_app):
    ngw_webtest_app.get('/api/component/component/method') Writing tests Naming conventions

Follow pytest default naming conventions - test modules and functions must have test_ prefix.


Do not forget to add a dummy __init__.py file to the test directory. Running tests

$ export NEXTGISWEB_CONFIG=path/to/config.ini
$ python -m pytest package                     # All tests from package
$ python -m pytest package/component           # Only tests from component
$ python -m pytest --pyargs package.component  # Same but by Python module name


The last option with --pyargs might be useful when running tests in Crater / NGWDocker environment. Path-based options won’t work because of symlinks inside site-packages directory.