task.replaceIsFalse("value_to_replace", "replaced_value")
              task.replaceKeyInDo("do_.some.key_to_replace", "do_.some.key_that_was_replaced")
              task.replaceKeyInDo("do_.some.key_to_replace_in_two", "do_.some.key_that_was_replaced_in_two", "two")
              task.replaceKeyInMatch("match_.some.key_to_replace", "match_.some.key_that_was_replaced")

      - inject:
          properties-file: '.ci/java-versions.properties'
          properties-content: |
            JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA
            RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
            JAVA8_HOME=$HOME/.java/java8
            JAVA11_HOME=$HOME/.java/java11
            JAVA15_HOME=$HOME/.java/openjdk15
      - shell: |
          #!/usr/local/bin/runbld --redirect-stderr

# Required by bats
sudo touch /etc/is_vagrant_vm
sudo useradd vagrant

set -e

. .ci/java-versions.properties
RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
BUILD_JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA

rm -Rfv $HOME/.gradle/init.d/ && mkdir -p $HOME/.gradle/init.d
cp -v .ci/init.gradle $HOME/.gradle/init.d

unset JAVA_HOME

if [ -f "/etc/os-release" ] ; then
    cat /etc/os-release
    . /etc/os-release

# Required by bats
sudo touch /etc/is_vagrant_vm
sudo useradd vagrant

set -e

. .ci/java-versions.properties
RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
BUILD_JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA

rm -Rfv $HOME/.gradle/init.d/ && mkdir -p $HOME/.gradle/init.d
cp -v .ci/init.gradle $HOME/.gradle/init.d

unset JAVA_HOME

if [ -f "/etc/os-release" ] ; then
    cat /etc/os-release
    . /etc/os-release

             Searching for package file structure from directories
             with <font color="#3465A4">__init__.py</font> files
             Importing from <font color="#75507B">/home/user/code/</font><font color="#AD7FA8">awesomeapp</font>

   <span style="background-color:#007166"><font color="#D3D7CF"> module </font></span>  🐍 main.py

        checkNotBinaryCompatibleKotlin(
            v1 = """
                class Source(some: String?) {
                    var someVar: String? = null
                    fun foo(bar: String?) {}
                }
            """,
            v2 = """
                class Source(some: String) {
                    var someVar: String = "some"
                    fun foo(bar: String) {}
                }
            """

If you are helping a lot of people with their questions, you will become an official [FastAPI Expert](fastapi-people.md#fastapi-experts). 🎉

Just remember, the most important point is: try to be kind. People come with their frustrations and in many cases don't ask in the best way, but try as best as you can to be kind. 🤗

# OpenAPI Webhooks { #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**.

      - inject:
          properties-file: '.ci/java-versions.properties'
          properties-content: |
            JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA
            RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
            JAVA8_HOME=$HOME/.java/java8
            JAVA11_HOME=$HOME/.java/java11
            JAVA15_HOME=$HOME/.java/openjdk15
      - shell: |
          #!/usr/local/bin/runbld --redirect-stderr

    node: "macosx && x86_64"
    builders:
      - inject:
          properties-file: '.ci/java-versions.properties'
          properties-content: |
            JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA
            RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
            JAVA15_HOME=$HOME/.java/openjdk15
      - shell: |
          #!/usr/local/bin/runbld --redirect-stderr