article.yml

title: Some title
date: 2018-03-12
Text: Lorem ipsum …

import.php

<?php 

require 'kirby/bootstrap.php';

// get the current list of blog articles
$articles = page('blog')->children();

// scan a directory with yaml files for each post
$files = Dir::read(__DIR__ . '/articles');

foreach ($files as $filename) {

    // read each yaml file
    $yaml = Data::read(__DIR__ . '/articles/' . $filename);
    $slug = Str::slug($yaml['title']);
    $template = 'article';
  
    $articles->create($slug, $template, [
      'title' => $yaml['title'],
      'date' => $yaml['date'],
      'text' => $yaml['text']
    ]);
    
}