meta-language-runtime-entities.html

<!DOCTYPE html>
<html lang="en">

<head>
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
  <title>Diggernaut: Documentation for Meta-Language | Runtime Entities | Basic Concepts</title>
  <meta name="description" content="This chapter discusses the digger runtime and its contexts.">
  <meta name="keywords" content="Diggernaut, scraping, web scraping, scraper, web scraper, meta-language, make scraper, scraper for websites, learning to scrape, data acquisition, create scraper, online scraper, content scraper, scraper for shop, scraper for classifieds, coding scraper, scraper runtime">
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
  <meta http-equiv="x-ua-compatible" content="ie=edge">

  <!-- Alternatives -->
  <link rel="canonical" href="https://www.diggernaut.com/dev/meta-language-runtime-entities.html"/>
  <link rel="alternate" hreflang="en" href="https://www.diggernaut.com/dev/meta-language-runtime-entities.html"/>
  <link rel="alternate" hreflang="ru" href="https://www.diggernaut.ru/dev/meta-yazyk-obyekty-sredy-vypolneniya.html"/>
  
  <!-- Twitter -->
  <meta name="twitter:card" content="summary_large_image">
  <meta name="twitter:creator" content="@diggernautcom">
  <meta name="twitter:site" content="@diggernautcom">
  <meta name="twitter:title" content="Diggernaut: Documentation for Meta-Language | Runtime Entities | Basic Concepts">
  <meta name="twitter:image" content="https://www.diggernaut.ru/static/dev/images/og_img_devml_en.png">

  <!-- OG -->
  <meta property="og:locale" content="en_US"/>
  <meta property="og:site_name" content="Diggernaut"/>
  <meta property="og:title" content="Diggernaut: Documentation for Meta-Language | Runtime Entities | Basic Concepts"/>
  <meta property="og:url" content="https://www.diggernaut.com/dev/meta-language-runtime-entities.html"/>
  <meta property="og:type" content="website"/>
  <meta property="og:description" content="This chapter discusses the digger runtime and its contexts."/>
  <meta property="og:image" content="https://www.diggernaut.ru/static/dev/images/og_img_devml_en.png"/>

  <!-- CSS  -->
  <link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
  <link href="css/flexboxgrid.min.css" type="text/css" rel="stylesheet" media="screen,projection"/>
  <link href="css/materialize.css" type="text/css" rel="stylesheet" media="screen,projection"/>
  <link href="css/style.css" type="text/css" rel="stylesheet" media="screen,projection"/>
  <link href="css/ml-style.css" type="text/css" rel="stylesheet" media="screen,projection"/>
  <link href="css/prism.css" type="text/css" rel="stylesheet" media="screen,projection"/>
  <link href="css/font-awesome.min.css" type="text/css" rel="stylesheet" media="screen,projection"/>
  <link href="css/gsce.css" type="text/css" rel="stylesheet" media="screen,projection"/>
  <script>
    (function () {
      var cx = '017044341280497706869:0g3mtgyp2is';
      var gcse = document.createElement('script');
      gcse.type = 'text/javascript';
      gcse.async = true;
      gcse.src = 'https://cse.google.com/cse.js?cx=' + cx;
      var s = document.getElementsByTagName('script')[0];
      s.parentNode.insertBefore(gcse, s);
    })();
  </script>
</head>

<body>
<header>
  <nav class="teal darken-1" role="navigation" id="menu">
    <div class="container-gcse">
      <gcse:search></gcse:search>
    </div>
  </nav>
</header>
<main>
  <div class="lessons-container" id="main">
    <div class="container">
      <h1>Runtime Entities</h1>

      <h2>Basic Concepts</h2>

      <p class="flow-text">
        The runtime is software environment available during the digger run. This environment consists of several contexts,
        and a digger, being started, is always in one of them at any time:
      </p>
      <p class="flow-text">
        <i>Digger Context</i> - The digger has not yet loaded the page or has already left the scope of the previously loaded page.<br/>
        <span class="spacer-10"></span>
        <i>Page Context</i> - The digger has loaded the page and is in the scope of this page.<br/>
        <span class="spacer-10"></span>
        <i>Block Context</i> - The digger has loaded the page, moved to a specific block on the page and is in the scope of this block.<br/>
        <span class="spacer-10"></span>
        <i>Form Context</i> - The digger has loaded the page, has moved to a specific form on the page and is in the scope of this form.<br/>
      </p>
      <p class="flow-text">
        <strong>A digger can be in a few contexts at the same time.</strong> So, for example, while the digger is running,
        it is always in a Digger Context, and as soon as it loads any page it goes into a Page Context
        and at the same time it is still in a Digger Context. Next, the scraper algorithm goes into the HTML node and falls into the Block Context,
        remaining at the same time in a Page and Digger Context. Depending on the context digger can interact with different entities and execute
        different commands with various options, selection of which may also depends on the context. Entities can be context-sensitive
        and context-independent. Context-independent entities does not change values when context is changed and remains intact until its changed manually.
      </p>

      <p class="flow-text">
        To better understanding, please take a look at the picture below.
      </p>

      <img src="img/meta-language/scope_en.png" class="responsive-img materialboxed z-depth-2" alt="">
      <span class="spacer"></span>

      <blockquote class="warning darken-1">
        <p class="flow-text">
          You can not change the configuration while the digger is running. <br/>
          It is necessary to stop the digger, make the required changes and start again.
        </p>
      </blockquote>

      <div class="row">
        <div class="col-xs-12 col-lg-12 col-md-12 col-sm-12">
          <div class="pagination">
            <a href="meta-language-runtime-entities-register.html" class="btn goto teal z-depth-2">Next</a>
          </div>
        </div>
      </div>

    </div>
  </div>
</main>

<footer class="page-footer teal darken-1">
  <div class="container">
    <div class="row">
      <div class="col-xs-12 col-lg-12 col-md-12 col-sm-12">
        <div class="social">
          <a class="btn btn-floating btn-flat" href="https://www.diggernaut.com/blog/category/learning-meta-language/"
            target="_blank"><i class="fa fa-wordpress"></i></a>
          <a class="btn btn-floating btn-flat" href="https://vk.com/diggernaut" target="_blank"><i class="fa fa-vk"></i></a>
          <a class="btn btn-floating btn-flat" href="https://www.facebook.com/diggernaut/" target="_blank"><i class="fa fa-facebook"></i></a>
          <a class="btn btn-floating btn-flat" href="https://www.linkedin.com/company/10908957/" target="_blank"><i class="fa fa-linkedin"></i></a>
          <a class="btn btn-floating btn-flat" href="https://twitter.com/diggernautcom" target="_blank"><i class="fa fa-twitter"></i></a>
        </div>
      </div>
    </div>
  </div>
</footer>

<!--  Scripts-->
<script src="js/jquery-2.2.3.min.js"></script>
<script src="js/materialize.min.js"></script>
<script src="js/prism.js"></script>
<script src="js/meta-language-init.js"></script>

<!-- Google analytics -->
<script>
  (function (i, s, o, g, r, a, m) {
    i['GoogleAnalyticsObject'] = r;
    i[r] = i[r] || function () {
      (i[r].q = i[r].q || []).push(arguments)
    }, i[r].l = 1 * new Date();
    a = s.createElement(o),
        m = s.getElementsByTagName(o)[0];
    a.async = 1;
    a.src = g;
    m.parentNode.insertBefore(a, m)
  })(window, document, 'script', 'https://www.google-analytics.com/analytics.js', 'ga');
  ga('create', 'UA-80717561-1', 'auto');
  ga('send', 'pageview');
</script>
<!-- /Google analytics -->

<!-- Yandex.Metrika counter -->
<script type="text/javascript" >
  (function (d, w, c) {
      (w[c] = w[c] || []).push(function() {
          try {
              w.yaCounter47560513 = new Ya.Metrika({
                  id:47560513,
                  clickmap:true,
                  trackLinks:true,
                  accurateTrackBounce:true
              });
          } catch(e) { }
      });

      var n = d.getElementsByTagName("script")[0],
          s = d.createElement("script"),
          f = function () { n.parentNode.insertBefore(s, n); };
      s.type = "text/javascript";
      s.async = true;
      s.src = "https://mc.yandex.ru/metrika/watch.js";

      if (w.opera == "[object Opera]") {
          d.addEventListener("DOMContentLoaded", f, false);
      } else { f(); }
  })(document, window, "yandex_metrika_callbacks");
</script>
<noscript><div><img src="https://mc.yandex.ru/watch/47560513" style="position:absolute; left:-9999px;" alt="" /></div></noscript>
<!-- /Yandex.Metrika counter -->

</body>
</html>