## Mounting a **FastAPI** application { #mounting-a-fastapi-application }

"Mounting" means adding a completely "independent" application in a specific path, that then takes care of handling everything under that path, with the _path operations_ declared in that sub-application.

### Top-level application { #top-level-application }

#!/usr/bin/env bash

echo "Running $0"

if [ -n "$TEST_DEBUG" ]; then
	set -x
fi

trap 'catch $LINENO' ERR

# shellcheck disable=SC2120
catch() {
	if [ $# -ne 0 ]; then
		echo "error on line $1"
		for site in sitea siteb sitec; do
			echo "$site server logs ========="
			cat "/tmp/${site}_1.log"
			echo "==========================="
			cat "/tmp/${site}_2.log"
		done
	fi

	echo "Cleaning up instances of MinIO"

		case "Endpoint":
			z.Endpoint, err = dc.ReadString()
			if err != nil {
				err = msgp.WrapError(err, "Endpoint")
				return
			}
		case "Token":
			z.Token, err = dc.ReadString()
			if err != nil {
				err = msgp.WrapError(err, "Token")
				return
			}
		default:
			err = dc.Skip()
			if err != nil {
				err = msgp.WrapError(err)
				return
			}
		}
	}
	return
}

	STATUS=$?
	if [ $STATUS -eq 0 ]; then
		DATA_DRIVE=1
	fi

	if [ $DATA_DRIVE -eq -1 ]; then
		# Check for existence of file in erasure set 2
		docker exec resiliency-minio1-1 /bin/sh -c "stat /data5/test-bucket/$DIR/$FILE/xl.meta" >/dev/null 2>&1
		STATUS=$?
		if [ $STATUS -eq 0 ]; then
			DATA_DRIVE=5
		fi
	fi
	echo $DATA_DRIVE
}

In the previous example, we were returning a `dict` from our dependency ("dependable"):

{* ../../docs_src/dependencies/tutorial001_an_py310.py hl[9] *}

But then we get a `dict` in the parameter `commons` of the *path operation function*.

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.

///

### `startup` and `shutdown` together { #startup-and-shutdown-together }

There's a high chance that the logic for your *startup* and *shutdown* is connected, you might want to start something and then finish it, acquire a resource and then release it, etc.

Doing that in separated functions that don't share logic or variables together is more difficult as you would need to store values in global variables or similar tricks.

export TFCI="$(echo $TFCI | sed 's/,nightly_upload/,public_cache,disk_cache/')"
if [[ -n "${TF_ANY_EXTRA_ENV:-}" ]]; then
  export TFCI="$TFCI,$TF_ANY_EXTRA_ENV"
fi
if [[ -n "${TF_ANY_SCRIPT:-}" ]]; then
  "$TF_ANY_SCRIPT"
elif [[ -n "${TF_ANY_TARGETS:-}" ]]; then
  source "${BASH_SOURCE%/*}/utilities/setup.sh"
  tfrun bazel "${TF_ANY_MODE:-test}" $TFCI_BAZEL_COMMON_ARGS $TF_ANY_TARGETS
else

        SpnegoContext ctx = newContext();

        // The initial token path should ask the mechanism for a zero-length optimistic token
        when(this.mechContext.getFlags()).thenReturn(0x1234);
        when(this.mechContext.initSecContext(any(byte[].class), eq(0), eq(0))).thenReturn(new byte[] { 0x01, 0x02 });

        // Act: len==0 triggers initial token construction
        byte[] out = ctx.initSecContext(null, 0, 0);

        startLatch.countDown();

        // Wait for completion
        assertTrue(endLatch.await(30, TimeUnit.SECONDS), "All threads should complete within timeout");
        executor.shutdown();

        // Then - Verify no exceptions occurred
        if (!exceptions.isEmpty()) {
            fail("Concurrent operations caused exceptions: " + exceptions.get(0));
        }

    }

    @Test
    void testAvailable_ok() {
        checkGetMethod(Collections.emptyMap(), getAvailableEndpointSuffix() + "/").then().body("response.status", equalTo(0));
    }

    @Test
    void testInstall_ng() {
        checkPostMethod(Collections.emptyMap(), getInstallEndpointSuffix()).then().body("response.status", equalTo(1));
    }