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How to Add Env Variable to Pytest?

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In order to add an environment variable to pytest, you can use the pytest command followed by the --env flag and the name of the environment variable you want to set. For example, to add an environment variable named MY_ENV_VAR with a value of testing, you can run pytest --env MY_ENV_VAR=testing. This will make the environment variable available to your pytest tests during execution.

How to store environment variables securely in pytest?

To store environment variables securely in pytest, you can use the pytest-env plugin. This plugin allows you to define environment variables in a secure way in a configuration file.

Here are the steps to store environment variables securely in pytest using the pytest-env plugin:

  1. Install the pytest-env plugin by running the following command:

pip install pytest-env

  1. Create a configuration file (e.g., pytest.ini or setup.cfg) in your project directory and define your environment variables in the [pytest] section. For example:

[pytest] env = MY_SECRET_KEY=your_secret_key API_URL=https://api.example.com

  1. In your test files, access the environment variables using the os.environ dictionary. For example:

import os

def test_api_call(): api_url = os.environ.get('API_URL') secret_key = os.environ.get('MY_SECRET_KEY')

# Make API call using the environment variables
  1. Run your tests using the pytest command and the pytest-env plugin will automatically load the environment variables defined in the configuration file.

By following these steps, you can store and access environment variables securely in pytest using the pytest-env plugin.

How to share environment variables across multiple pytest sessions?

To share environment variables across multiple pytest sessions, you can use a pytest plugin called "pytest-env". This plugin allows you to define environment variables in a configuration file (such as pytest.ini or conftest.py) and access them in your test cases.

Here's how you can use pytest-env to share environment variables across multiple pytest sessions:

  1. Install the pytest-env plugin by running the following command: pip install pytest-env
  2. Create a configuration file (e.g. pytest.ini) in your project directory and define the environment variables that you want to share across pytest sessions: [pytest] env = ENV_VAR1=value1 ENV_VAR2=value2
  3. In your test cases, you can access the environment variables using the os.environ dictionary. For example: import os def test_env_variables(): assert os.environ.get('ENV_VAR1') == 'value1' assert os.environ.get('ENV_VAR2') == 'value2'
  4. Run your pytest sessions as usual and the environment variables defined in the configuration file will be available to all test cases.

By following these steps, you can easily share environment variables across multiple pytest sessions using the pytest-env plugin.

How to create temporary environment variables for pytest?

To create temporary environment variables for pytest, you can use the monkeypatch fixture provided by pytest. Here is an example of how to set a temporary environment variable for a pytest test:

# test_example.py

import os

def test_example(monkeypatch): monkeypatch.setenv('TEMP_VAR', '123')

assert os.getenv('TEMP\_VAR') == '123'

In this example, the monkeypatch fixture is passed as an argument to the test function. The setenv method of the monkeypatch fixture is used to set the temporary environment variable TEMP_VAR to the value '123'. The os.getenv function is then used to access the value of the temporary environment variable within the test.

You can run this test by executing pytest test_example.py. The temporary environment variable will be set only during the execution of this specific test and will not affect the environment outside of the test.

What is the impact of environment variables on pytest performance?

Environment variables can have a significant impact on pytest performance. By setting specific environment variables, you can control various aspects of pytest behavior such as test execution, reporting, logging, and more. Here are a few ways in which environment variables can affect pytest performance:

  1. Test configuration: Environment variables can be used to specify test configuration settings, such as the test directory, test file patterns, test markers, and more. By setting these variables, you can customize pytest behavior to meet your specific testing requirements, which can ultimately improve performance.
  2. Parallel test execution: Environment variables such as PYTEST_XDIST_PROC can be used to enable parallel test execution with pytest-xdist plugin. This can significantly improve test execution times by running multiple tests concurrently on different processes or machines.
  3. Logging and reporting: Environment variables such as PYTEST_LOG_LEVEL can be used to control the verbosity of log messages generated during test execution. By adjusting logging settings, you can reduce unnecessary output and improve performance.
  4. Code coverage: Environment variables such as PYTEST_COVERAGE can be used to enable code coverage measurement during test execution. This can impact performance as collecting code coverage information incurs a slight overhead.

Overall, environment variables can play a crucial role in optimizing pytest performance by fine-tuning test configurations, enabling parallel test execution, controlling logging and reporting, and managing code coverage. However, it is important to carefully consider the impact of each environment variable on performance and only use those that are necessary for your testing requirements.

How to remove environment variables from pytest?

To remove environment variables from pytest, you can use the following steps:

  1. Open the terminal or command prompt where you are running pytest.
  2. To remove a single environment variable, use the following command: unset ENV_VARIABLE_NAME Replace ENV_VARIABLE_NAME with the specific environment variable name you want to remove.
  3. To remove multiple environment variables at once, you can use the following command: unset ENV_VAR1 ENV_VAR2 ENV_VAR3 Replace ENV_VAR1, ENV_VAR2, ENV_VAR3, etc. with the names of the environment variables you want to remove.
  4. Alternatively, you can also remove all environment variables by using the following command: env -i pytest This command will run pytest with a clean environment, removing all environment variables that were previously set.

By following these steps, you can effectively remove environment variables from pytest and run your tests without any unwanted variables affecting the results.

How to add environment variable to pytest in Linux?

To add an environment variable to pytest in Linux, you can use the -c option along with the name and value of the variable. Here is the command to add an environment variable to pytest in Linux:

$ pytest -c "ENV_VARIABLE_NAME=VALUE" test_file.py

Replace ENV_VARIABLE_NAME with the name of the environment variable you want to add and VALUE with its value. You can add multiple environment variables by separating them with spaces like this:

$ pytest -c "ENV_VAR1=VALUE1 ENV_VAR2=VALUE2" test_file.py

Alternatively, you can also add environment variables by setting them before running pytest using the export command in the terminal:

$ export ENV_VARIABLE_NAME=VALUE $ pytest test_file.py

This will set the environment variable for the duration of the terminal session where pytest is run.