# Behind a Proxy

In some situations, you might need to use a **proxy** server like Traefik or Nginx with a configuration that adds an extra path prefix that is not seen by your application.

In these cases you can use `root_path` to configure your application.

The `root_path` is a mechanism provided by the ASGI specification (that FastAPI is built on, through Starlette).

The `root_path` is used to handle these specific cases.

And we know that editors can't provide a lot of support (like completion) for `dict`s, because they can't know their keys and value types.

We can do better...

## What makes a dependency

Up to now you have seen dependencies declared as functions.

But that's not the only way to declare dependencies (although it would probably be the more common).

The key factor is that a dependency should be a "callable".

!!! info
    Selbst, nachdem OpenAPI 3.1.0 veröffentlicht wurde, mit dieser neuen, einfacheren Integration mit JSON Schema, unterstützte Swagger UI, das Tool, das die automatische Dokumentation bereitstellt, eine Zeit lang OpenAPI 3.1.0 nicht (das tut es seit Version 5.0.0 🎉).

| `Forwarded`   | For outgoing requests, the original source IP. Note that since we spoof IPs in most cases, this usually is the same as the actual IP seen. For incoming requests, this is used only for traffic from waypoints (which are trusted and cannot spoof IPs) |

   *
   * <p>This class is accessible but not supported in GWT as it references {@link
   * PermittedMetaException}.
   */
  protected final class MultiExceptionListIterator implements ListIterator<E> {
    // TODO: track seen elements when order isn't guaranteed
    // TODO: verify contents afterward
    // TODO: something shiny and new instead of Stack
    // TODO: test whether null is supported (create a Feature)
    /**

      echo "For dependency $dep:"
      # For every missing dependency, find the tests which directly depend on
      # it, and print that list for debugging. Not really clear if this is
      # helpful since the only examples I've seen are enormous.
      bazel cquery "rdeps(kind(py_test, $(cat $BATS_TEST_TMPDIR/deps)), $dep, 1)"
    done < $BATS_TEST_TMPDIR/missing_deps
    exit 1
  fi
}

You can learn how to use them and how they are integrated into **FastAPI** later in the **Advanced User Guide**.

## Recap

With what you have seen up to now, you can set up a secure **FastAPI** application using standards like OAuth2 and JWT.

In almost any framework handling the security becomes a rather complex subject quite quickly.

// IsOnline - returns whether RPC client failed to connect or not.
func (client *storageRESTClient) IsOnline() bool {
	return client.gridConn.State() == grid.StateConnected
}

// LastConn - returns when the disk is seen to be connected the last time
func (client *storageRESTClient) LastConn() time.Time {
	return client.restClient.LastConn()
}

func (client *storageRESTClient) IsLocal() bool {
	return false
}

  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.Time lastScaleTime = 2;

  // currentReplicas is current number of replicas of pods managed by this autoscaler,
  // as last seen by the autoscaler.
  optional int32 currentReplicas = 3;

  // desiredReplicas is the desired number of replicas of pods managed by this autoscaler,
  // as last calculated by the autoscaler.

  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.Time lastScaleTime = 2;

  // currentReplicas is current number of replicas of pods managed by this autoscaler,
  // as last seen by the autoscaler.
  optional int32 currentReplicas = 3;

  // desiredReplicas is the desired number of replicas of pods managed by this autoscaler,
  // as last calculated by the autoscaler.