# Lifespan Events

You can define logic (code) that should be executed before the application **starts up**. This means that this code will be executed **once**, **before** the application **starts receiving requests**.

The same way, you can define logic (code) that should be executed when the application is **shutting down**. In this case, this code will be executed **once**, **after** having handled possibly **many requests**.

	if err != nil {
		t.Fatalf("Test %s: Failed to create HTTP request for RemoveBucketHandler: <ERROR> %v", instanceType, err)
	}
	// Since `apiRouter` satisfies `http.Handler` it has a ServeHTTP to execute the logic of the handler.
	// Call the ServeHTTP to execute the handler.
	apiRouter.ServeHTTP(rec, req)
	switch rec.Code {
	case http.StatusOK, http.StatusCreated, http.StatusAccepted, http.StatusNoContent:

# Custom Request and APIRoute class

In some cases, you may want to override the logic used by the `Request` and `APIRoute` classes.

In particular, this may be a good alternative to logic in a middleware.

For example, if you want to read or manipulate the request body before it is processed by your application.

/// danger

This is an "advanced" feature.

If you are just starting with **FastAPI** you might want to skip this section.

///

        String adjustment = "";

        if (parent != null) {
            String childName = child.getArtifactId();

            /*
             * This logic (using filesystem, against wanted independence from the user environment) exists only for the
             * sake of backward-compat with 2.x (MNG-5000). In general, it is wrong to

                + replacement.getVersionRange() + " to: " + newRange + " )");
    }

    /**
     * The logic used here used to be a copy of the logic used in the DefaultArtifactCollector, and this method was
     * called right before the actual version/artifactScope changes were done. However, a different set of conditionals

                    },
                }
            },
        },
        "tags": [
            {
                "name": "users",
                "description": "Operations with users. The **login** logic is also here.",
            },
            {
                "name": "items",
                "description": "Manage items. So _fancy_ they have their own docs.",
                "externalDocs": {

		if err != nil {
			t.Fatalf("Test %d: %s: Failed to create HTTP request for PutBucketPolicyHandler: <ERROR> %v", i+1, instanceType, err)
		}
		// Since `apiRouter` satisfies `http.Handler` it has a ServeHTTP to execute the logic of the handler.
		// Call the ServeHTTP to execute the handler.
		apiRouter.ServeHTTP(recV4, reqV4)
		if recV4.Code != testCase.expectedRespStatus {

		t.Fatal("no policies found")
	}

	if policies[0] != "consoleAdmin" {
		t.Fatalf("expected 'consoleAdmin', %s", policies[0])
	}
}

// TestSkipContentSha256Cksum - Test validate the logic which decides whether
// to skip checksum validation based on the request header.
func TestSkipContentSha256Cksum(t *testing.T) {
	testCases := []struct {
		inputHeaderKey   string
		inputHeaderValue string

  // it will be compatible with it: the name will be updated by device placement
  // logic to refer to the specific device chosen.
  //
  // Example: If one calls `op->SetDeviceName("/device:GPU")`, the value
  // returned by DeviceName should be "/device:GPU:*" until a particular GPU is
  // chosen for the operation by the device placement logic in the
  // executor. After that, the value returned by DeviceName will be a full

 This is the model for Maven toolchain in <<<org.apache.maven.toolchain>>> package,
 delegating content to {{{../api/maven-api-toolchain/index.html}Maven 4 API immutable toolchain}}. All the effective model
 building logic from multiple toolchains files is done in {{{../maven-toolchain-builder/}Maven Toolchain Builder}}.

 The following are generated from this model: