```

#### Behind a TLS Termination Proxy

If you are running your container behind a TLS Termination Proxy (load balancer) like Nginx or Traefik, add the option `--proxy-headers`, this will tell Uvicorn (through the FastAPI CLI) to trust the headers sent by that proxy telling it that the application is running behind HTTPS, etc.

```Dockerfile
CMD ["fastapi", "run", "app/main.py", "--proxy-headers", "--port", "80"]
```

---
title: Recipes
description: A collection of common/useful code examples for Kotlin and Java
---


# Recipes

We've written some recipes that demonstrate how to solve common problems with OkHttp. Read through them to learn about how everything works together. Cut-and-paste these examples freely; that's what they're for.

### Synchronous Get ([.kt][SynchronousGetKotlin], [.java][SynchronousGetJava])

even when the mutex <i>l</i> is unlocked.
</p>

<h3 id="once">Once</h3>

<p>
The <code>sync</code> package provides a safe mechanism for
initialization in the presence of multiple goroutines
through the use of the <code>Once</code> type.
Multiple threads can execute <code>once.Do(f)</code> for a particular <code>f</code>,
but only one will run <code>f()</code>, and the other calls block
until <code>f()</code> has returned.

      // extensive testing
      try {
        return Double.parseDouble(string);
      } catch (NumberFormatException e) {
        // Double.parseDouble has changed specs several times, so fall through
        // gracefully
      }
    }
    return null;
  }

func NewEndpoints(args ...string) (endpoints Endpoints, err error) {
	var endpointType EndpointType
	var scheme string

	uniqueArgs := set.NewStringSet()
	// Loop through args and adds to endpoint list.
	for i, arg := range args {
		endpoint, err := NewEndpoint(arg)
		if err != nil {
			return nil, fmt.Errorf("'%s': %s", arg, err.Error())
		}

  * Logs usage and root filesystem usage of a container, volumes usage of a pod and node disk usage are exposed through Kubelet new metrics API.

### Experimental Features

  * Dynamic Provisioning of PersistentVolumes: Kubernetes previously required all
volumes to be manually provisioned by a cluster administrator before use. With

* Resolves a bug that prevented sending a multi-version custom resource to an admission webhook. ([#79495](https://github.com/kubernetes/kubernetes/pull/79495), [@liggitt](https://github.com/liggitt))
* Pass-through volume MountOptions to global mount (NodeStageVolume) on the node for CSI ([#80191](https://github.com/kubernetes/kubernetes/pull/80191), [@davidz627](https://github.com/davidz627))

    // for use calling Collection.toArray later
    T[] emptyArray = Platform.newArray(strictlyOrderedElements, 0);

    // shoot me, but I didn't want to deal with wildcards through the whole test
    @SuppressWarnings("unchecked")
    Scenario<T> starter = new Scenario<>((Ordering<T>) ordering, list, emptyArray);
    verifyScenario(starter, 0);
  }

    // for use calling Collection.toArray later
    T[] emptyArray = Platform.newArray(strictlyOrderedElements, 0);

    // shoot me, but I didn't want to deal with wildcards through the whole test
    @SuppressWarnings("unchecked")
    Scenario<T> starter = new Scenario<>((Ordering<T>) ordering, list, emptyArray);
    verifyScenario(starter, 0);
  }

		tracker.logSuccess()
		return true
	}
	return false
}

// diskHealthWrapper provides either a io.Reader or io.Writer
// that updates status of the provided tracker.
// Use through diskHealthReader or diskHealthWriter.
type diskHealthWrapper struct {
	tracker *healthDiskCtxValue
	r       io.Reader
	w       io.Writer
}

func (d *diskHealthWrapper) Read(p []byte) (int, error) {