meta-language-methods-working-with-dom-nodes.html

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      <h1>Methods for Working with DOM</h1>

      <div>
        <h2>Nodes</h2>

        <p class="flow-text">
          When a digger is working with HTML or XML document, it works with <a href="https://en.wikipedia.org/wiki/Document_Object_Model" target="_blank">DOM (Domain Object Model)</a> structure of the document.
          So basically such document consists of nodes. When you use the <span class = "hlt2">find</span> method, you search through nodes of the document, switch
          to the found node and, respectively, to block context. Inside the current block (node) there can be nested (child) nodes,
          and they also may have child nodes and so on. In a block context, you can manipulate the nodes of the current block,
          delete or replace them.
        </p>

        <p class="flow-text">
          Examples of commands you can use for nodes manipulations:
        </p>

        <pre class="language-yaml">
          <code class="language-yaml"># DELETE ALL NON-TEXT CHILD NODES
- node_remove_all
        </code></pre>

        <pre class="language-yaml">
          <code class="language-yaml"># DELETE ALL `а` NODES
- node_remove: a
        </code></pre>

        <pre class="language-yaml">
          <code class="language-yaml"># REPLACE ALL `а` NODES TO EMPTY `p` NODES
- node_replace:
    path: a
    with: &lt;p&gt;&lt;/p&gt;
        </code></pre>

        <pre class="language-yaml">
          <code class="language-yaml"># REPLACE ALL `а` NODES TO THEIR CONTENTS
- node_replace:
    path: a
    with: content
        </code></pre>

        <span class="spacer"></span>

        <p class="flow-text">
          Let's use following HTML source as example:
        </p>

        <pre class="language-markup">
          <code class="language-markup">&lt;div&gt;
    &lt;span&gt;some text&lt;/span&gt;
    &lt;a&gt;some link&lt;/a&gt;
    &lt;span&gt;another text&lt;/span&gt;
&lt;/div&gt;
            </code></pre>

        <p class="flow-text">
          Examples of usage:
        </p>

        <div class="row">
          <div class="col s12">
            <ul class="tabs excdark">
              <li class="tab col s6"><a class="active" href="#node_remove_all">Delete all nodes</a></li>
              <li class="tab col s6"><a href="#node_remove">Delete nodes by CSS selector</a></li>
              <li class="tab col s6"><a href="#node_replace">Replace nodes</a></li>
              <li class="tab col s6"><a href="#node_replace_content">Replace with node contents</a></li>
            </ul>
          </div>

          <div id="node_remove_all" class="col s12">
            <pre class="language-yaml">
              <code class="language-yaml">- find:
    path: div
    do:
    - node_remove_all
    - parse

    # REGISTER WILL BE EMPTY AS ALL NODES WERE REMOVED
              </code></pre>
          </div>

          <div id="node_remove" class="col s12">
            <pre class="language-yaml">
              <code class="language-yaml">- find:
    path: div
    do:
    - node_remove: span
    - parse

    # REGISTER VALUE: some link
    # BECAUSE ALL `span` NODES WERE REMOVED
              </code></pre>
          </div>

          <div id="node_replace" class="col s12">
            <pre class="language-yaml">
              <code class="language-yaml">- find:
    path: div
    do:
    - node_replace: 
        path: span
        with: ' some text '
    - parse

    # REGISTER VALUE: " some text some link some text "
    # BECAUSE ALL `span` NODES WERE REPLACED WITH TEXT " some text "
              </code></pre>
          </div>

          <div id="node_replace_content" class="col s12">
            <pre class="language-yaml">
              <code class="language-yaml">- find:
    path: div
    do:
    - node_replace: 
        path: span
        with: content
    - parse

    # REGISTER VALUE: some textsome linksome text
    # BECAUSE ALL `span` NODES WERE REPLACED WITH THEIR CONTENTS
              </code></pre>
          </div>
        </div>

        <p class="flow-text">
          In the next chapter, we learn how to manipulate the attributes of a node.
        </p>

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