# 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

# ==============================================================================
#
# Changes the behavior in pycpp.sh from "run all tests" to "verify that all
# tests can compile." Used in some CI jobs (macOS and Linux Arm64) where test
# execution is too expensive.
TFCI_PYCPP_SWAP_TO_BUILD_ENABLE=1

import okhttp3.internal.platform.Platform

/**
 * Computes the effective certificate chain from the raw array returned by Java's built in TLS APIs.
 * Cleaning a chain returns a list of certificates where the first element is `chain[0]`, each
 * certificate is signed by the certificate that follows, and the last certificate is a trusted CA
 * certificate.
 *

  //   where the endpoint is located. This should match the corresponding
  //   node label.
  // * topology.kubernetes.io/zone: the value indicates the zone where the
  //   endpoint is located. This should match the corresponding node label.
  // * topology.kubernetes.io/region: the value indicates the region where the
  //   endpoint is located. This should match the corresponding node label.

   * compressed stream that is terminated in a web socket frame even though the DEFLATE stream is
   * not terminated.
   *
   * Use this method to create a degenerate Okio Buffer where each byte is in a separate segment of
   * the internal list.
   */
  @JvmStatic
  fun fragmentBuffer(buffer: Buffer): Buffer {
    // Write each byte into a new buffer, then clone it so that the segments are shared.

import okhttp3.internal.platform.AndroidPlatform
import okhttp3.internal.platform.Platform

/**
 * Modern reflection based SocketAdapter for Conscrypt class SSLSockets.
 *
 * This is used directly for providers where class name is known e.g. the Google Play Provider
 * but we can't compile directly against it, or in fact reliably know if it is registered and
 * on classpath.
 */

  - Suppose the VCS root you just create is `MyNewVcsRoot`. Set "default branch" to `myTestBranch` where your code exists.
- Click `Create subproject` button at the bottom of the "Subprojects" region of [this page](https://builds.gradle.org/admin/editProject.html?projectId=Gradle&tab=projectGeneralTab)
  - Select `Manually`.

    Temporarily adopting this point of view (of the *external developer*) can help you feel like it's more obvious where to put the parameters, the Pydantic model for the body, for the response, etc. for that *external API*.

### Create a callback `APIRouter`

First create a new `APIRouter` that will contain one or more callbacks.

// package's DefaultScheme has conversion functions installed which will unpack the
// JSON stored in RawExtension, turning it into the correct object type, and storing it
// in the Object. (TODO: In the case where the object is of an unknown type, a
// runtime.Unknown object will be created and stored.)
//
// +k8s:deepcopy-gen=true
// +protobuf=true
// +k8s:openapi-gen=true
message RawExtension {

/**
 * A certificate chain cleaner that uses a set of trusted root certificates to build the trusted
 * chain. This class duplicates the clean chain building performed during the TLS handshake. We
 * prefer other mechanisms where they exist, such as with
 * [okhttp3.internal.platform.AndroidPlatform.AndroidCertificateChainCleaner].
 *
 * This class includes code from [Conscrypt's][Conscrypt] [TrustManagerImpl] and
 * [TrustedCertificateIndex].
 *