Display Post Excerpt To The More Tag With WP API V2

functions-1.php

<?php

function my_rest_prepare_post( $data, $post, $request ) {

	$_data = $data->data;

	$excerpt = get_extended( $post->post_content );
	$_data['my_excerpt'] = $excerpt['main'];

	$data->data = $_data;

	return $data;
}
add_filter( 'rest_prepare_post', 'my_rest_prepare_post', 10, 3 );

functions-2.php

<?php
function my_rest_prepare_post( $data, $post, $request ) {

	$_data = $data->data;
	$excerpt = get_extended( apply_filters( 'the_content', $post->post_content ) );
	$_data['my_excerpt'] = $excerpt['main'];

	$data->data = $_data;

	return $data;
}
add_filter( 'rest_prepare_post', 'my_rest_prepare_post', 10, 3 );

functions.php

<?php
function my_rest_prepare_post( $data, $post, $request ) {

	$_data = $data->data;

	$excerpt = get_the_content();
	$_data['my_excerpt'] = $excerpt;

	$data->data = $_data;

	return $data;
}
add_filter( 'rest_prepare_post', 'my_rest_prepare_post', 10, 3 );