How to add rst format in nodes for directive?

Question

How I can use rst in nodes? For example I want to output icluded file about.rst

class Foo(Directive):

    def run(self):
        return [
            nodes.Text("**adad**"),  # <-- Must be a bold text
            nodes.Text(".. include:: about.rst"),  # <-- Must include file
        ]

Answer 1

You can construct a ViewList of your raw rst data (one line per entry), get Sphinx to parse that content, and then return the nodes Sphinx gives you. The following worked for me:

from docutils import nodes
from docutils.statemachine import ViewList
from sphinx.util.compat import Directive
from sphinx.util.nodes import nested_parse_with_titles

class Foo(Directive):
    def run(self):
        rst = ViewList()

        # Add the content one line at a time.
        # Second argument is the filename to report in any warnings
        # or errors, third argument is the line number.            
        rst.append("**adad**", "fakefile.rst", 10)
        rst.append("", "fakefile.rst", 11)
        rst.append(".. include:: about.rst", "fakefile.rst", 12)

        # Create a node.
        node = nodes.section()
        node.document = self.state.document

        # Parse the rst.
        nested_parse_with_titles(self.state, rst, node)

        # And return the result.
        return node.children

def setup(app):
    app.add_directive('foo', Foo)

I had to do something similar for a project --- in lieu of any (easily found) relevant documentation I used the source of the inbuilt autodoc extension as a guide.