old_contents: from __future__ import absolute_import
  
  from django.views.decorators.csrf import csrf_exempt
  
  from zerver.decorator import authenticated_json_post_view, has_request_variables, REQ
  from zerver.lib.actions import internal_send_message
  from zerver.lib.response import json_error, json_success
  from zerver.lib.validator import check_string
  from zerver.models import UserProfile
  
  from zerver.lib.rest import rest_dispatch as _rest_dispatch
  rest_dispatch = csrf_exempt((lambda request, *args, **kwargs: _rest_dispatch(request, globals(), *args, **kwargs)))
  
  @authenticated_json_post_view
  @has_request_variables
  def json_tutorial_send_message(request, user_profile, type=REQ,
                                 recipient=REQ, topic=REQ, content=REQ):
      """
      This function, used by the onboarding tutorial, causes the Tutorial Bot to
      send you the message you pass in here. (That way, the Tutorial Bot's
      messages to you get rendered by the server and therefore look like any other
      message.)
      """
      sender_name = "welcome-bot@zulip.com"
      if type == 'stream':
          internal_send_message(sender_name, "stream", recipient, topic, content,
                                realm=user_profile.realm)
          return json_success()
      # For now, there are no PM cases.
      return json_error('Bad data passed in to tutorial_send_message')
  
  @authenticated_json_post_view
  @has_request_variables
  def json_tutorial_status(request, user_profile, status=REQ('status')):
      if status == 'started':
          user_profile.tutorial_status = UserProfile.TUTORIAL_STARTED
      elif status == 'finished':
          user_profile.tutorial_status = UserProfile.TUTORIAL_FINISHED
      user_profile.save(update_fields=["tutorial_status"])
  
      return json_success()
  
  
new_contents: from __future__ import absolute_import
  
  from django.views.decorators.csrf import csrf_exempt
  
  from zerver.decorator import authenticated_json_post_view, has_request_variables, REQ
  from zerver.lib.actions import internal_send_message
  from zerver.lib.response import json_error, json_success
  from zerver.lib.validator import check_string
  from zerver.models import UserProfile
  
  from zerver.lib.rest import rest_dispatch as _rest_dispatch
  rest_dispatch = csrf_exempt((lambda request, *args, **kwargs: _rest_dispatch(request, globals(), *args, **kwargs)))
  
  @authenticated_json_post_view
  @has_request_variables
  def json_tutorial_send_message(request, user_profile, type=REQ(validator=check_string),
                                 recipient=REQ(validator=check_string), topic=REQ(validator=check_string),
                                 content=REQ(validator=check_string)):
      """
      This function, used by the onboarding tutorial, causes the Tutorial Bot to
      send you the message you pass in here. (That way, the Tutorial Bot's
      messages to you get rendered by the server and therefore look like any other
      message.)
      """
      sender_name = "welcome-bot@zulip.com"
      if type == 'stream':
          internal_send_message(sender_name, "stream", recipient, topic, content,
                                realm=user_profile.realm)
          return json_success()
      # For now, there are no PM cases.
      return json_error('Bad data passed in to tutorial_send_message')
  
  @authenticated_json_post_view
  @has_request_variables
  def json_tutorial_status(request, user_profile,
                           status=REQ(validator=check_string)):
      if status == 'started':
          user_profile.tutorial_status = UserProfile.TUTORIAL_STARTED
      elif status == 'finished':
          user_profile.tutorial_status = UserProfile.TUTORIAL_FINISHED
      user_profile.save(update_fields=["tutorial_status"])
  
      return json_success()
  
  
subject: Add string validators to tutorial routes.