Clean Markdown with dedent to respect indents (apache#16414)

(cherry picked from commit 6f9c0ce)
(cherry picked from commit 4c06aae)
(cherry picked from commit 26abb8d)

airflow/www/utils.py

@@ -16,6 +16,7 @@
 # specific language governing permissions and limitations
 # under the License.
 import json
+import textwrap
 import time
 from urllib.parse import urlencode
 
@@ -322,9 +323,7 @@ def wrapped_markdown(s, css_class='rich_doc'):
     """Convert a Markdown string to HTML."""
     if s is None:
         return None
-
-    s = '\n'.join(line.lstrip() for line in s.split('\n'))
-
+    s = textwrap.dedent(s)
     return Markup(f'<div class="{css_class}" >' + markdown.markdown(s, extensions=['tables']) + "</div>")
 
 

tests/www/test_utils.py

@@ -213,3 +213,39 @@ def test_wrapped_markdown_with_indented_lines(self):
         )
 
         assert '<div class="rich_doc" ><h1>header</h1>\n<p>1st line\n2nd line</p></div>' == rendered
+
+    def test_wrapped_markdown_with_raw_code_block(self):
+        rendered = wrapped_markdown(
+            """\
+            # Markdown code block
+
+            Inline `code` works well.
+
+                Code block
+                does not
+                respect
+                newlines
+
+            """
+        )
+
+        assert (
+            '<div class="rich_doc" ><h1>Markdown code block</h1>\n'
+            '<p>Inline <code>code</code> works well.</p>\n'
+            '<pre><code>Code block\ndoes not\nrespect\nnewlines\n</code></pre></div>'
+        ) == rendered
+
+    def test_wrapped_markdown_with_nested_list(self):
+        rendered = wrapped_markdown(
+            """
+            ### Docstring with a code block
+
+            - And
+                - A nested list
+            """
+        )
+
+        assert (
+            '<div class="rich_doc" ><h3>Docstring with a code block</h3>\n'
+            '<ul>\n<li>And<ul>\n<li>A nested list</li>\n</ul>\n</li>\n</ul></div>'
+        ) == rendered