+def to_ascii(x: str):
+ """Encode as ascii bytes string.
+
+ >>> to_ascii('test')
+ b'test'
+
+ >>> to_ascii(b'1, 2, 3')
+ b'1, 2, 3'
+
+ """
+ if type(x) is str:
+ return x.encode('ascii')
+ if type(x) is bytes:
+ return x
+ raise Exception('to_ascii works with strings and bytes')
+
+
+def to_base64(txt: str, *, encoding='utf-8', errors='surrogatepass') -> str:
+ """Encode txt and then encode the bytes with a 64-character
+ alphabet. This is compatible with uudecode.
+
+ >>> to_base64('hello?')
+ b'aGVsbG8/\\n'
+
+ """
+ return base64.encodebytes(txt.encode(encoding, errors))
+
+
+def is_base64(txt: str) -> bool:
+ """Determine whether a string is base64 encoded (with Python's standard
+ base64 alphabet which is the same as what uuencode uses).
+
+ >>> is_base64('test') # all letters in the b64 alphabet
+ True
+
+ >>> is_base64('another test, how do you like this one?')
+ False
+
+ >>> is_base64(b'aGVsbG8/\\n') # Ending newline is ok.
+ True
+
+ """
+ a = string.ascii_uppercase + string.ascii_lowercase + string.digits + '+/'
+ alphabet = set(a.encode('ascii'))
+ for char in to_ascii(txt.strip()):
+ if char not in alphabet:
+ return False
+ return True
+
+
+def from_base64(b64: str, encoding='utf-8', errors='surrogatepass') -> str:
+ """Convert base64 encoded string back to normal strings.
+
+ >>> from_base64(b'aGVsbG8/\\n')
+ 'hello?'
+
+ """
+ return base64.decodebytes(b64).decode(encoding, errors)
+
+
+def chunk(txt: str, chunk_size):
+ """Chunk up a string.
+
+ >>> ' '.join(chunk('010011011100010110101010101010101001111110101000', 8))
+ '01001101 11000101 10101010 10101010 10011111 10101000'
+
+ """
+ if len(txt) % chunk_size != 0:
+ msg = f'String to chunk\'s length ({len(txt)} is not an even multiple of chunk_size ({chunk_size})'
+ logger.warning(msg)
+ warnings.warn(msg)
+ for x in range(0, len(txt), chunk_size):
+ yield txt[x:x+chunk_size]
+
+
+def to_bitstring(txt: str, *, delimiter='', encoding='utf-8', errors='surrogatepass') -> str:
+ """Encode txt and then chop it into bytes. Note: only bitstrings
+ with delimiter='' are interpretable by from_bitstring.
+
+ >>> to_bitstring('hello?')
+ '011010000110010101101100011011000110111100111111'
+
+ >>> to_bitstring('test', delimiter=' ')
+ '01110100 01100101 01110011 01110100'
+
+ >>> to_bitstring(b'test')
+ '01110100011001010111001101110100'
+
+ """
+ etxt = to_ascii(txt)
+ bits = bin(
+ int.from_bytes(
+ etxt,
+ 'big'
+ )
+ )
+ bits = bits[2:]
+ return delimiter.join(chunk(bits.zfill(8 * ((len(bits) + 7) // 8)), 8))
+
+
+def is_bitstring(txt: str) -> bool:
+ """Is this a bitstring?
+
+ >>> is_bitstring('011010000110010101101100011011000110111100111111')
+ True
+
+ >>> is_bitstring('1234')
+ False
+
+ """
+ return is_binary_integer_number(f'0b{txt}')
+
+
+def from_bitstring(bits: str, encoding='utf-8', errors='surrogatepass') -> str:
+ """Convert from bitstring back to bytes then decode into a str.
+
+ >>> from_bitstring('011010000110010101101100011011000110111100111111')
+ 'hello?'
+
+ """
+ n = int(bits, 2)
+ return n.to_bytes((n.bit_length() + 7) // 8, 'big').decode(encoding, errors) or '\0'
+
+
+def ip_v4_sort_key(txt: str) -> Tuple[int]:
+ """Turn an IPv4 address into a tuple for sorting purposes.
+
+ >>> ip_v4_sort_key('10.0.0.18')
+ (10, 0, 0, 18)
+
+ >>> ips = ['10.0.0.10', '100.0.0.1', '1.2.3.4', '10.0.0.9']
+ >>> sorted(ips, key=lambda x: ip_v4_sort_key(x))
+ ['1.2.3.4', '10.0.0.9', '10.0.0.10', '100.0.0.1']
+
+ """
+ if not is_ip_v4(txt):
+ print(f"not IP: {txt}")
+ return None
+ return tuple([int(x) for x in txt.split('.')])
+
+
+def path_ancestors_before_descendants_sort_key(volume: str) -> Tuple[str]:
+ """Chunk up a file path so that parent/ancestor paths sort before
+ children/descendant paths.
+
+ >>> path_ancestors_before_descendants_sort_key('/usr/local/bin')
+ ('usr', 'local', 'bin')
+
+ >>> paths = ['/usr/local', '/usr/local/bin', '/usr']
+ >>> sorted(paths, key=lambda x: path_ancestors_before_descendants_sort_key(x))
+ ['/usr', '/usr/local', '/usr/local/bin']
+
+ """
+ return tuple([x for x in volume.split('/') if len(x) > 0])
+
+
+def replace_all(in_str: str, replace_set: str, replacement: str) -> str:
+ """Execute several replace operations in a row.
+
+ >>> s = 'this_is a-test!'
+ >>> replace_all(s, ' _-!', '')
+ 'thisisatest'
+
+ """
+ for char in replace_set:
+ in_str = in_str.replace(char, replacement)
+ return in_str
+
+
projects / python_utils.git / blobdiff