Defer docutils imports until help is rendered

.changes/next-release/enhancement-startup-22805.json

@@ -0,0 +1,5 @@
+{
+  "type": "enhancement",
+  "category": "startup",
+  "description": "Defer importing ``docutils`` until help output is actually rendered. It was previously imported on every CLI invocation, along with ``pygments`` and ``PIL``, even for commands that never render help."
+}

awscli/clidriver.py

@@ -65,11 +65,6 @@
 )
 from awscli.formatter import get_formatter
 from awscli.handlers_registry import MAIN_COMMAND_TABLE_OPS
-from awscli.help import (
-    OperationHelpCommand,
-    ProviderHelpCommand,
-    ServiceHelpCommand,
-)
 from awscli.lazy_emitter import LazyInitEmitter
 from awscli.logger import (
     disable_crt_logging,
@@ -534,6 +529,10 @@ def _create_cli_argument(self, option_name, option_params):
         )
 
     def create_help_command(self):
+        # Imported here because the help machinery pulls in docutils,
+        # which is only needed when help is actually requested.
+        from awscli.help import ProviderHelpCommand
+
         cli_data = self._get_cli_data()
         return ProviderHelpCommand(
             self.session,
@@ -769,6 +768,8 @@ def _add_lineage(self, command_table):
             command_obj.lineage = self.lineage + [command_obj]
 
     def create_help_command(self):
+        from awscli.help import ServiceHelpCommand
+
         command_table = self._get_command_table()
         return ServiceHelpCommand(
             session=self.session,
@@ -964,6 +965,8 @@ def __call__(self, args, parsed_globals):
             )
 
     def create_help_command(self):
+        from awscli.help import OperationHelpCommand
+
         return OperationHelpCommand(
             self._session,
             operation_model=self._operation_model,

awscli/help.py

@@ -20,11 +20,6 @@
 from subprocess import PIPE, Popen
 
 from botocore.exceptions import ProfileNotFound
-from docutils.core import publish_string
-from docutils.writers import (
-    html4css1,
-    manpage,
-)
 
 from awscli import (
     _DEFAULT_BASE_REMOTE_URL,
@@ -239,6 +234,9 @@ class PosixHelpRenderer(PosixPagingHelpRenderer):
     """
 
     def _convert_doc_content(self, contents):
+        from docutils.core import publish_string
+        from docutils.writers import manpage
+
         settings_overrides = self._DEFAULT_DOCUTILS_SETTINGS_OVERRIDES.copy()
         settings_overrides["report_level"] = 3
         man_contents = publish_string(
@@ -265,6 +263,9 @@ class PosixBrowserHelpRenderer(BrowserHelpRenderer):
     """
 
     def _convert_doc_content(self, contents):
+        from docutils.core import publish_string
+        from docutils.writers import manpage
+
         settings_overrides = self._DEFAULT_DOCUTILS_SETTINGS_OVERRIDES.copy()
         settings_overrides["report_level"] = 3
         man_contents = publish_string(
@@ -310,6 +311,8 @@ class WindowsHelpRenderer(WindowsPagingHelpRenderer):
     """Render help content on a Windows platform."""
 
     def _convert_doc_content(self, contents):
+        from docutils.core import publish_string
+
         text_output = publish_string(
             contents,
             writer=TextWriter(),
@@ -322,6 +325,9 @@ class WindowsBrowserHelpRenderer(BrowserHelpRenderer):
     """Render help content in the browser on a Windows platform."""
 
     def _convert_doc_content(self, contents):
+        from docutils.core import publish_string
+        from docutils.writers import html4css1
+
         text_output = publish_string(
             contents,
             writer=html4css1.Writer(),

awscli/topictags.py

@@ -22,8 +22,6 @@
 import json
 import os
 
-import docutils.core
-
 
 class TopicTagDB:
     """This class acts like a database for the tags of all available topics.
@@ -182,7 +180,10 @@ def _find_topic_name(self, topic_src_file):
 
     def _add_tag_and_values_from_content(self, topic_name, content):
         # Retrieves tags and values and adds from content of topic file
-        # to the dictionary.
+        # to the dictionary.  Imported here because docutils is only
+        # needed when the topic index is (re)generated or queried.
+        import docutils.core
+
         doctree = docutils.core.publish_doctree(content).asdom()
         fields = doctree.getElementsByTagName('field')
         for field in fields: