# OpenAPI Webhooks

There are cases where you want to tell your API **users** that your app could call *their* app (sending a request) with some data, normally to **notify** of some type of **event**.

This means that instead of the normal process of your users sending requests to your API, it's **your API** (or your app) that could **send requests to their system** (to their API, their app).

This is normally called a **webhook**.

## Webhooks steps

Nevertheless, you would probably also want to have something outside making sure to **restart Gunicorn** if necessary, and also to **run it on startup**, etc.

## Uvicorn with Workers

Uvicorn also has an option to start and run several **worker processes**.

// It would be cool if there was a hook that I could use to set up a test environment.
// I want to set up a local/remote repositories for testing but I don't want to have
// to change them when I change the layout of the repositories. So I want to generate
// the structure I want to test by using the artifact handler manager which dictates
// the layout used for a particular artifact type.

/**
 */

```

Dans cet exemple, nous n'avons déclaré aucun modèle Pydantic. En fait, le corps de la requête n'est même pas <abbr title="converti d'un format simple, comme des octets, en objets Python">parsé</abbr> en tant que JSON, il est lu directement en tant que `bytes`, et la fonction `magic_data_reader()` serait chargé de l'analyser d'une manière ou d'une autre.

Néanmoins, nous pouvons déclarer le schéma attendu pour le corps de la requête.

				VersionID:   "",
				IsLatest:    true,
				NumVersions: 1,
			},
			want: 0,
			lc:   lc,
		},
	}
	for i, tc := range tests {
		t.Run(fmt.Sprintf("test-%d", i+1), func(t *testing.T) {
			if got := tc.lc.FilterRules(tc.opts); len(got) != tc.want {
				t.Fatalf("Expected %d rules to match but got %d", tc.want, len(got))
			}
			w := httptest.NewRecorder()
			tc.lc.SetPredictionHeaders(w, tc.opts)

    * This is particularly important for **security**, we'll see more of that below.

## `response_model` Parameter

There are some cases where you need or want to return some data that is not exactly what the type declares.

### One Process per Container

In this type of scenario, you probably would want to have **a single (Uvicorn) process per container**, as you would already be handling replication at the cluster level.

So, in this case, you **would not** want to have a process manager like Gunicorn with Uvicorn workers, or Uvicorn using its own Uvicorn workers. You would want to have just a **single Uvicorn process** per container (but probably multiple containers).

			want, err := readFile(outPath)
			if err != nil {
				t.Fatal(err)
			}

			if got != want {
				diff, err := compare.ManifestDiffWithRenameSelectIgnore(got, want,
					"", diffSelect, tt.diffIgnore, false)
				if err != nil {
					t.Fatal(err)
				}
				if diff != "" {
					t.Fatalf("%s: got:\n%s\nwant:\n%s\n(-got, +want)\n%s\n", tt.desc, "", "", diff)
				}

For example, let's say that you want to use <a href="https://github.com/ijl/orjson" class="external-link" target="_blank">`orjson`</a>, but with some custom settings not used in the included `ORJSONResponse` class.

Let's say you want it to return indented and formatted JSON, so you want to use the orjson option `orjson.OPT_INDENT_2`.

    val ansiControlSequenceUtil = "net.rubygrapefruit:ansi-control-sequence-util"
    val ant = "org.apache.ant:ant"
    val antLauncher = "org.apache.ant:ant-launcher"
    val antJunit = "org.apache.ant:ant-junit"
    val asm = "org.ow2.asm:asm"
    val asmAnalysis = "org.ow2.asm:asm-analysis"
    val asmCommons = "org.ow2.asm:asm-commons"