You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
96 lines
3.1 KiB
Python
96 lines
3.1 KiB
Python
"""Variable class for URITemplate."""
|
|
|
|
from __future__ import annotations
|
|
|
|
from .charset import Charset
|
|
|
|
|
|
class VariableInvalidError(Exception):
|
|
"""Exception thrown for invalid variables."""
|
|
|
|
variable: str
|
|
|
|
def __init__(self, variable: str) -> None:
|
|
self.variable = variable
|
|
|
|
def __str__(self) -> str:
|
|
"""Convert to string."""
|
|
return 'Bad variable: ' + self.variable
|
|
|
|
|
|
class Variable:
|
|
"""
|
|
A template variable.
|
|
|
|
https://tools.ietf.org/html/rfc6570#section-2.3
|
|
"""
|
|
|
|
name: str
|
|
key: str
|
|
max_length: int
|
|
explode: bool
|
|
array: bool
|
|
default: (str | None)
|
|
|
|
def __init__(self, var_spec: str) -> None:
|
|
self.name = ''
|
|
self.key = ''
|
|
self.max_length = 0
|
|
self.explode = False
|
|
self.array = False
|
|
self.default = None
|
|
|
|
if (var_spec[0:1] not in Charset.VAR_START):
|
|
raise VariableInvalidError(var_spec)
|
|
|
|
if ('=' in var_spec):
|
|
var_spec, self.default = var_spec.split('=', 1)
|
|
|
|
if (':' in var_spec):
|
|
var_spec, max_length = var_spec.split(':', 1)
|
|
if ((0 < len(max_length)) and (len(max_length) < 4)):
|
|
for digit in max_length:
|
|
if (digit not in Charset.DIGIT):
|
|
raise VariableInvalidError(var_spec + ':' + max_length)
|
|
self.max_length = int(max_length)
|
|
if (not self.max_length):
|
|
raise VariableInvalidError(var_spec + ':' + max_length)
|
|
else:
|
|
raise VariableInvalidError(var_spec + ':' + max_length)
|
|
elif ('*' == var_spec[-1]):
|
|
var_spec = var_spec[:-1]
|
|
self.explode = True
|
|
elif ('[]' == var_spec[-2:]):
|
|
var_spec = var_spec[:-2]
|
|
self.array = True
|
|
self.explode = True
|
|
|
|
index = 0
|
|
while (index < len(var_spec)):
|
|
codepoint = var_spec[index]
|
|
if (('%' == codepoint)
|
|
and ((index + 2) < len(var_spec))
|
|
and (var_spec[index + 1] in Charset.HEX_DIGIT)
|
|
and (var_spec[index + 2] in Charset.HEX_DIGIT)):
|
|
self.key += var_spec[index:index + 3]
|
|
index += 2
|
|
elif (codepoint in Charset.VAR_CHAR):
|
|
self.key += codepoint
|
|
elif ('/' == codepoint):
|
|
self.name = self.key
|
|
self.key = ''
|
|
else:
|
|
raise VariableInvalidError(var_spec + ((':' + str(self.max_length)) if (self.max_length) else '')
|
|
+ ('[]' if (self.array) else ('*' if (self.explode) else '')))
|
|
index += 1
|
|
|
|
self.name = (self.name or self.key)
|
|
self.key = (self.key or self.name)
|
|
|
|
def __str__(self) -> str:
|
|
"""Convert to string."""
|
|
return (self.name + (f'/{self.key}' if (self.key and (self.key != self.name)) else '')
|
|
+ (f':{self.max_length}' if (self.max_length) else '')
|
|
+ ('*' if (self.explode and not self.array) else '') + ('[]' if (self.array) else '')
|
|
+ (f'={self.default}' if (self.default is not None) else ''))
|