# Query Parameter Models { #query-parameter-models }

If you have a group of **query parameters** that are related, you can create a **Pydantic model** to declare them.

This would allow you to **re-use the model** in **multiple places** and also to declare validations and metadata for all the parameters at once. 😎

/// note

This is supported since FastAPI version `0.115.0`. 🤓

///

            .map { (_, v) -> listOf(v.maxOrNull()!!.format()) }.flatten()
    }

    private
    fun VersionNumber.format() =
        // reformat according to our versioning scheme, since toString() would typically convert 1.0 to 1.0.0
        // starting with Gradle 9.0, the version number is always 3 digits (SemVer)

    response = client.get("/v1/")
    assert response.status_code == 200, response.text
    assert response.text == "Hello, World from Flask!"


def test_app():
    response = client.get("/v2")
    assert response.status_code == 200, response.text

// least `max_values`.
//
// The elements of values will point to addresses in `storage` which must be at
// least `storage_size` bytes in length.  Ideally, max_values would be set to
// TF_AttrMetadata.list_size and `storage` would be at least
// TF_AttrMetadata.total_size, obtained from TF_OperationGetAttrMetadata(oper,
// attr_name).
//
// Fails if storage_size is too small to hold the requested number of strings.

         * inserts checks automatically for non-private functions (which are the only kind that we
         * check).
         *
         * We *would* just check such functions redundantly, but kotlinc emits its nullness
         * annotations in the form of JetBrains annotations, which have only class retention and

     * field should be used for calculating that. This would likely be zero
     * but an implemantation that encorporates the transport header(for
     * efficiency) might use a different initial bufferIndex. For example,
     * to eliminate copying data when writing NbtSession data one might
     * manage that 4 byte header specifically and therefore the initial
     * bufferIndex, and thus headerStart, would be 4).(NOTE: If one where

     * @param version The version of the POM, must not be {@code null}.
     * @return The source of the requested POM, never {@code null}.
     * @throws UnresolvableModelException If the POM could not be resolved from any configured repository.
     */
    ModelSource resolveModel(String groupId, String artifactId, String version) throws UnresolvableModelException;

    /**

   * {@link PermittedMetaException} instances, which wrap a set of all exceptions that the iterator
   * could throw during the invocation of that method. This is necessary because, e.g., a call to
   * {@code iterator().remove()} of an unmodifiable list could throw either {@link
   * IllegalStateException} or {@link UnsupportedOperationException}. Note that iterator

)
def test_router_events(state: State) -> None:
    app = FastAPI()

    @app.get("/")
    def main() -> dict[str, str]:
        return {"message": "Hello World"}

    @app.on_event("startup")
    def app_startup() -> None:
        state.app_startup = True

    @app.on_event("shutdown")
    def app_shutdown() -> None:
        state.app_shutdown = True

 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.maven.embedder;

/**
 * Hello world!
 *
 */
public class App
{
    public static void main( String[] args )
    {
        System.out.println( "Hello World!" );
    }