test_logging.py

import logging
import sys
from io import StringIO

import pytest

from flask.logging import default_handler
from flask.logging import has_level_handler
from flask.logging import wsgi_errors_stream


@pytest.fixture(autouse=True)
def reset_logging(pytestconfig):
    root_handlers = logging.root.handlers[:]
    logging.root.handlers = []
    root_level = logging.root.level

    logger = logging.getLogger("flask_test")
    logger.handlers = []
    logger.setLevel(logging.NOTSET)

    logging_plugin = pytestconfig.pluginmanager.unregister(name="logging-plugin")

    yield

    logging.root.handlers[:] = root_handlers
    logging.root.setLevel(root_level)

    logger.handlers = []
    logger.setLevel(logging.NOTSET)

    if logging_plugin:
        pytestconfig.pluginmanager.register(logging_plugin, "logging-plugin")


def test_logger(app):
    assert app.logger.name == "flask_test"
    assert app.logger.level == logging.NOTSET
    assert app.logger.handlers == [default_handler]


def test_logger_debug(app):
    app.debug = True
    assert app.logger.level == logging.DEBUG
    assert app.logger.handlers == [default_handler]


def test_existing_handler(app):
    logging.root.addHandler(logging.StreamHandler())
    assert app.logger.level == logging.NOTSET
    assert not app.logger.handlers


def test_wsgi_errors_stream(app, client):
    @app.route("/")
    def index():
        app.logger.error("test")
        return ""

    stream = StringIO()
    client.get("/", errors_stream=stream)
    assert "ERROR in test_logging: test" in stream.getvalue()

    assert wsgi_errors_stream._get_current_object() is sys.stderr

    with app.test_request_context(errors_stream=stream):
        assert wsgi_errors_stream._get_current_object() is stream


def test_has_level_handler():
    logger = logging.getLogger("flask.app")
    assert not has_level_handler(logger)

    handler = logging.StreamHandler()
    logging.root.addHandler(handler)
    assert has_level_handler(logger)

    logger.propagate = False
    assert not has_level_handler(logger)
    logger.propagate = True

    handler.setLevel(logging.ERROR)
    assert not has_level_handler(logger)


def test_log_view_exception(app, client):
    @app.route("/")
    def index():
        raise Exception("test")

    app.testing = False
    stream = StringIO()
    rv = client.get("/", errors_stream=stream)
    assert rv.status_code == 500
    assert rv.data
    err = stream.getvalue()
    assert "Exception on / [GET]" in err
    assert "Exception: test" in err