| """ |
| requests._internal_utils |
| ~~~~~~~~~~~~~~ |
| |
| Provides utility functions that are consumed internally by Requests |
| which depend on extremely few external helpers (such as compat) |
| """ |
| import re |
| |
| from .compat import builtin_str |
| |
| _VALID_HEADER_NAME_RE_BYTE = re.compile(rb"^[^:\s][^:\r\n]*$") |
| _VALID_HEADER_NAME_RE_STR = re.compile(r"^[^:\s][^:\r\n]*$") |
| _VALID_HEADER_VALUE_RE_BYTE = re.compile(rb"^\S[^\r\n]*$|^$") |
| _VALID_HEADER_VALUE_RE_STR = re.compile(r"^\S[^\r\n]*$|^$") |
| |
| HEADER_VALIDATORS = { |
| bytes: (_VALID_HEADER_NAME_RE_BYTE, _VALID_HEADER_VALUE_RE_BYTE), |
| str: (_VALID_HEADER_NAME_RE_STR, _VALID_HEADER_VALUE_RE_STR), |
| } |
| |
| |
| def to_native_string(string, encoding="ascii"): |
| """Given a string object, regardless of type, returns a representation of |
| that string in the native string type, encoding and decoding where |
| necessary. This assumes ASCII unless told otherwise. |
| """ |
| if isinstance(string, builtin_str): |
| out = string |
| else: |
| out = string.decode(encoding) |
| |
| return out |
| |
| |
| def unicode_is_ascii(u_string): |
| """Determine if unicode string only contains ASCII characters. |
| |
| :param str u_string: unicode string to check. Must be unicode |
| and not Python 2 `str`. |
| :rtype: bool |
| """ |
| assert isinstance(u_string, str) |
| try: |
| u_string.encode("ascii") |
| return True |
| except UnicodeEncodeError: |
| return False |
