That's what makes it possible to have multiple automatic interactive documentation interfaces, code generation, etc.

OpenAPI has a way to define multiple security "schemes".

By using them, you can take advantage of all these standard-based tools, including these interactive documentation systems.

OpenAPI defines the following security schemes:

* `apiKey`: an application specific key that can come from:
    * A query parameter.
    * A header.

 * may never contain more than {@link Integer#MAX_VALUE} occurrences of any one element.
 *
 * <p>{@code Multiset} refines the specifications of several methods from {@code Collection}. It
 * also defines an additional query operation, {@link #count}, which returns the count of an
 * element. There are five new bulk-modification operations, for example {@link #add(Object, int)},

 * may never contain more than {@link Integer#MAX_VALUE} occurrences of any one element.
 *
 * <p>{@code Multiset} refines the specifications of several methods from {@code Collection}. It
 * also defines an additional query operation, {@link #count}, which returns the count of an
 * element. There are five new bulk-modification operations, for example {@link #add(Object, int)},

# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.
#

#
# Maven system properties
#
# The properties defined in this file will be made available through
# system properties at the very beginning of Maven's boot process.
#

maven.installation.conf = ${maven.home}/conf
maven.user.conf         = ${user.home}/.m2

build:mkl --define=build_with_mkl=true --define=enable_mkl=true
build:mkl --define=tensorflow_mkldnn_contraction_kernel=0
build:mkl --define=build_with_openmp=true
build:mkl -c opt

# config to build OneDNN backend with a user specified threadpool.
build:mkl_threadpool --define=build_with_mkl=true --define=enable_mkl=true
build:mkl_threadpool --define=tensorflow_mkldnn_contraction_kernel=0

    class InterfaceMethodContractTest {

        @Test
        @DisplayName("Should define exactly four public methods")
        void shouldDefineExactlyFourPublicMethods() {
            java.lang.reflect.Method[] methods = SmbSession.class.getDeclaredMethods();
            assertEquals(4, methods.length, "SmbSession should define exactly 4 methods");
        }

        @Test

 */
@TestInstance(TestInstance.Lifecycle.PER_CLASS)
class FileInformationTest {

    /**
     * Test that interface constants are correctly defined
     */
    @Test
    @DisplayName("Test FileInformation constants are correctly defined")
    void testInterfaceConstants() {
        // Verify all constants have expected values
        assertEquals((byte) 20, FileInformation.FILE_ENDOFFILE_INFO);

# Lifespan Events { #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**.

* `PUT`: to update data.
* `DELETE`: to delete data.

So, in OpenAPI, each of the HTTP methods is called an "operation".

We are going to call them "**operations**" too.

#### Define a *path operation decorator* { #define-a-path-operation-decorator }

{* ../../docs_src/first_steps/tutorial001.py hl[6] *}

The `@app.get("/")` tells **FastAPI** that the function right below is in charge of handling requests that go to:

    * Because pydantic data structures are just instances of classes you define; auto-completion, linting, mypy and your intuition should all work properly with your validated data.
* Validate **complex structures**:
    * Use of hierarchical Pydantic models, Python `typing`’s `List` and `Dict`, etc.
    * And validators allow complex data schemas to be clearly and easily defined, checked and documented as JSON Schema.