django-rest-framework/rest_framework/utils/formatting.py
2019-08-07 21:05:24 +02:00

94 lines
2.9 KiB
Python

"""
Utility functions to return a formatted name and description for a given view.
"""
import re
from django.utils.encoding import force_str
from django.utils.html import escape
from django.utils.safestring import mark_safe
from rest_framework.compat import apply_markdown
def remove_trailing_string(content, trailing):
"""
Strip trailing component `trailing` from `content` if it exists.
Used when generating names from view classes.
"""
if content.endswith(trailing) and content != trailing:
return content[:-len(trailing)]
return content
def dedent(content):
"""
Remove leading indent from a block of text.
Used when generating descriptions from docstrings.
Note that python's `textwrap.dedent` doesn't quite cut it,
as it fails to dedent multiline docstrings that include
unindented text on the initial line.
"""
content = force_str(content)
lines = [line for line in content.splitlines()[1:] if line.lstrip()]
# unindent the content if needed
if lines:
whitespace_counts = min([len(line) - len(line.lstrip(' ')) for line in lines])
tab_counts = min([len(line) - len(line.lstrip('\t')) for line in lines])
if whitespace_counts:
whitespace_pattern = '^' + (' ' * whitespace_counts)
content = re.sub(re.compile(whitespace_pattern, re.MULTILINE), '', content)
elif tab_counts:
whitespace_pattern = '^' + ('\t' * tab_counts)
content = re.sub(re.compile(whitespace_pattern, re.MULTILINE), '', content)
return content.strip()
def camelcase_to_spaces(content):
"""
Translate 'CamelCaseNames' to 'Camel Case Names'.
Used when generating names from view classes.
"""
camelcase_boundary = '(((?<=[a-z])[A-Z])|([A-Z](?![A-Z]|$)))'
content = re.sub(camelcase_boundary, ' \\1', content).strip()
return ' '.join(content.split('_')).title()
def markup_description(description):
"""
Apply HTML markup to the given description.
"""
if apply_markdown:
description = apply_markdown(description)
else:
description = escape(description).replace('\n', '<br />')
description = '<p>' + description + '</p>'
return mark_safe(description)
class lazy_format:
"""
Delay formatting until it's actually needed.
Useful when the format string or one of the arguments is lazy.
Not using Django's lazy because it is too slow.
"""
__slots__ = ('format_string', 'args', 'kwargs', 'result')
def __init__(self, format_string, *args, **kwargs):
self.result = None
self.format_string = format_string
self.args = args
self.kwargs = kwargs
def __str__(self):
if self.result is None:
self.result = self.format_string.format(*self.args, **self.kwargs)
self.format_string, self.args, self.kwargs = None, None, None
return self.result
def __mod__(self, value):
return str(self) % value