# Testing Dependencies with Overrides

## Overriding dependencies during testing

There are some scenarios where you might want to override a dependency during testing.

You don't want the original dependency to run (nor any of the sub-dependencies it might have).

```python
from fastapi import Depends
```

::: fastapi.Depends

## `Security()`

For many scenarios, you can handle security (authorization, authentication, etc.) with dependencies, using `Depends()`.

But when you want to also declare OAuth2 scopes, you can use `Security()` instead of `Depends()`.

You can import `Security()` directly from `fastapi`:

```python
from fastapi import Security
```

Let's look at how we can make that work.

## pytest.mark.anyio

This means that you can send only the data that you want to update, leaving the rest intact.

!!! note
    `PATCH` is less commonly used and known than `PUT`.

    And many teams use only `PUT`, even for partial updates.

    You are **free** to use them however you want, **FastAPI** doesn't impose any restrictions.

```bash
helm get values my-release > old_values.yaml
```

Then change the field `image.tag` in `old_values.yaml` file with MinIO image tag you want to use. Now update the chart using

```bash
helm upgrade -f old_values.yaml my-release minio/minio
```

            description = "The extra gradle parameters you want to pass to this build, e.g. `-PrerunAllTests` or `--no-build-cache`"
        )
        text(
            "reverse.dep.*.additional.gradle.parameters",
            "",
            display = ParameterDisplay.NORMAL,
            allowEmpty = true,

    return delegate!!.useClientMode
  }

  override fun setNeedClientAuth(need: Boolean) {
    delegate!!.needClientAuth = need
  }

  override fun setWantClientAuth(want: Boolean) {
    delegate!!.wantClientAuth = want
  }

  override fun getNeedClientAuth(): Boolean {
    return delegate!!.needClientAuth
  }

  override fun getWantClientAuth(): Boolean {
    return delegate!!.wantClientAuth

opt_einsum == 3.3.0
astunparse == 1.6.3
dill == 0.3.7
astor == 0.7.1
typing_extensions == 4.8.0
gast == 0.4.0
termcolor == 2.3.0
wrapt == 1.16.0
tblib == 2.0.0

# Install tensorboard, and keras
# Note that here we want the latest version that matches TF major.minor version
# Note that we must use nightly here as these are used in nightly jobs
# For release jobs, we will pin these on the release branch
keras-nightly ~= 3.0.0.dev

Nevertheless, you would probably also want to have something outside making sure to **restart Gunicorn** if necessary, and also to **run it on startup**, etc.

## Uvicorn with Workers

Uvicorn also has an option to start and run several **worker processes**.

# Development - Contributing

First, you might want to see the basic ways to [help FastAPI and get help](help-fastapi.md){.internal-link target=_blank}.

## Developing

If you already cloned the <a href="https://github.com/tiangolo/fastapi" class="external-link" target="_blank">fastapi repository</a> and you want to deep dive in the code, here are some guidelines to set up your environment.

### Virtual environment with `venv`