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78 lines
2.1 KiB
Plaintext
78 lines
2.1 KiB
Plaintext
# vim:fileencoding=utf-8
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# License: BSD Copyright: 2017, Kovid Goyal <kovid at kovidgoyal.net>
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# globals: crypto
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from __python__ import hash_literals
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from encodings import hexlify, urlsafe_b64decode, urlsafe_b64encode
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RFC_4122 = 1
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if jstype(crypto) is 'object' and crypto.getRandomValues:
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random_bytes = def (num):
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ans = Uint8Array(num or 16)
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crypto.getRandomValues(ans)
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return ans
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else:
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random_bytes = def (num):
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ans = Uint8Array(num or 16)
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for i in range(ans.length):
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ans[i] = Math.floor(Math.random() * 256)
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return ans
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def uuid4_bytes():
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data = random_bytes()
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data[6] = 0b01000000 | (data[6] & 0b1111)
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data[8] = (((data[8] >> 4) & 0b11 | 0b1000) << 4) | (data[8] & 0b1111)
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return data
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def as_str():
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h = this.hex
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return h[:8] + '-' + h[8:12] + '-' + h[12:16] + '-' + h[16:20] + '-' + h[20:]
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def uuid4():
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b = uuid4_bytes()
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return {
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'hex': hexlify(b),
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'bytes': b,
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'variant': RFC_4122,
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'version': 4,
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'__str__': as_str,
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'toString': as_str,
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}
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def num_to_string(numbers, alphabet, pad_to_length):
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ans = v'[]'
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alphabet_len = alphabet.length
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numbers = Array.prototype.slice.call(numbers)
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for v'var i = 0; i < numbers.length - 1; i++':
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x = divmod(numbers[i], alphabet_len)
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numbers[i] = x[0]
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numbers[i+1] += x[1]
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for v'var i = 0; i < numbers.length; i++':
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number = numbers[i]
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while number:
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x = divmod(number, alphabet_len)
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number = x[0]
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ans.push(alphabet[x[1]])
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if pad_to_length and pad_to_length > ans.length:
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ans.push(alphabet[0].repeat(pad_to_length - ans.length))
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return ans.join('')
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def short_uuid():
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# A totally random uuid encoded using only URL and filename safe characters
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return urlsafe_b64encode(random_bytes(), '')
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def short_uuid4():
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# A uuid4 encoded using only URL and filename safe characters
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return urlsafe_b64encode(uuid4_bytes(), '')
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def decode_short_uuid(val):
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return urlsafe_b64decode(val + '==')
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