Spaces:
Sleeping
Sleeping
File size: 11,444 Bytes
7d134e4 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 |
"""
Handlers for Content-Encoding.
See: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Encoding
"""
from __future__ import annotations
import codecs
import io
import typing
import zlib
from ._compat import brotli, zstd
from ._exceptions import DecodingError
class ContentDecoder:
def decode(self, data: bytes) -> bytes:
raise NotImplementedError() # pragma: no cover
def flush(self) -> bytes:
raise NotImplementedError() # pragma: no cover
class IdentityDecoder(ContentDecoder):
"""
Handle unencoded data.
"""
def decode(self, data: bytes) -> bytes:
return data
def flush(self) -> bytes:
return b""
class DeflateDecoder(ContentDecoder):
"""
Handle 'deflate' decoding.
See: https://stackoverflow.com/questions/1838699
"""
def __init__(self) -> None:
self.first_attempt = True
self.decompressor = zlib.decompressobj()
def decode(self, data: bytes) -> bytes:
was_first_attempt = self.first_attempt
self.first_attempt = False
try:
return self.decompressor.decompress(data)
except zlib.error as exc:
if was_first_attempt:
self.decompressor = zlib.decompressobj(-zlib.MAX_WBITS)
return self.decode(data)
raise DecodingError(str(exc)) from exc
def flush(self) -> bytes:
try:
return self.decompressor.flush()
except zlib.error as exc: # pragma: no cover
raise DecodingError(str(exc)) from exc
class GZipDecoder(ContentDecoder):
"""
Handle 'gzip' decoding.
See: https://stackoverflow.com/questions/1838699
"""
def __init__(self) -> None:
self.decompressor = zlib.decompressobj(zlib.MAX_WBITS | 16)
def decode(self, data: bytes) -> bytes:
try:
return self.decompressor.decompress(data)
except zlib.error as exc:
raise DecodingError(str(exc)) from exc
def flush(self) -> bytes:
try:
return self.decompressor.flush()
except zlib.error as exc: # pragma: no cover
raise DecodingError(str(exc)) from exc
class BrotliDecoder(ContentDecoder):
"""
Handle 'brotli' decoding.
Requires `pip install brotlipy`. See: https://brotlipy.readthedocs.io/
or `pip install brotli`. See https://github.com/google/brotli
Supports both 'brotlipy' and 'Brotli' packages since they share an import
name. The top branches are for 'brotlipy' and bottom branches for 'Brotli'
"""
def __init__(self) -> None:
if brotli is None: # pragma: no cover
raise ImportError(
"Using 'BrotliDecoder', but neither of the 'brotlicffi' or 'brotli' "
"packages have been installed. "
"Make sure to install httpx using `pip install httpx[brotli]`."
) from None
self.decompressor = brotli.Decompressor()
self.seen_data = False
self._decompress: typing.Callable[[bytes], bytes]
if hasattr(self.decompressor, "decompress"):
# The 'brotlicffi' package.
self._decompress = self.decompressor.decompress # pragma: no cover
else:
# The 'brotli' package.
self._decompress = self.decompressor.process # pragma: no cover
def decode(self, data: bytes) -> bytes:
if not data:
return b""
self.seen_data = True
try:
return self._decompress(data)
except brotli.error as exc:
raise DecodingError(str(exc)) from exc
def flush(self) -> bytes:
if not self.seen_data:
return b""
try:
if hasattr(self.decompressor, "finish"):
# Only available in the 'brotlicffi' package.
# As the decompressor decompresses eagerly, this
# will never actually emit any data. However, it will potentially throw
# errors if a truncated or damaged data stream has been used.
self.decompressor.finish() # pragma: no cover
return b""
except brotli.error as exc: # pragma: no cover
raise DecodingError(str(exc)) from exc
class ZStandardDecoder(ContentDecoder):
"""
Handle 'zstd' RFC 8878 decoding.
Requires `pip install zstandard`.
Can be installed as a dependency of httpx using `pip install httpx[zstd]`.
"""
# inspired by the ZstdDecoder implementation in urllib3
def __init__(self) -> None:
if zstd is None: # pragma: no cover
raise ImportError(
"Using 'ZStandardDecoder', ..."
"Make sure to install httpx using `pip install httpx[zstd]`."
) from None
self.decompressor = zstd.ZstdDecompressor().decompressobj()
def decode(self, data: bytes) -> bytes:
assert zstd is not None
output = io.BytesIO()
try:
output.write(self.decompressor.decompress(data))
while self.decompressor.eof and self.decompressor.unused_data:
unused_data = self.decompressor.unused_data
self.decompressor = zstd.ZstdDecompressor().decompressobj()
output.write(self.decompressor.decompress(unused_data))
except zstd.ZstdError as exc:
raise DecodingError(str(exc)) from exc
return output.getvalue()
def flush(self) -> bytes:
ret = self.decompressor.flush() # note: this is a no-op
if not self.decompressor.eof:
raise DecodingError("Zstandard data is incomplete") # pragma: no cover
return bytes(ret)
class MultiDecoder(ContentDecoder):
"""
Handle the case where multiple encodings have been applied.
"""
def __init__(self, children: typing.Sequence[ContentDecoder]) -> None:
"""
'children' should be a sequence of decoders in the order in which
each was applied.
"""
# Note that we reverse the order for decoding.
self.children = list(reversed(children))
def decode(self, data: bytes) -> bytes:
for child in self.children:
data = child.decode(data)
return data
def flush(self) -> bytes:
data = b""
for child in self.children:
data = child.decode(data) + child.flush()
return data
class ByteChunker:
"""
Handles returning byte content in fixed-size chunks.
"""
def __init__(self, chunk_size: int | None = None) -> None:
self._buffer = io.BytesIO()
self._chunk_size = chunk_size
def decode(self, content: bytes) -> list[bytes]:
if self._chunk_size is None:
return [content] if content else []
self._buffer.write(content)
if self._buffer.tell() >= self._chunk_size:
value = self._buffer.getvalue()
chunks = [
value[i : i + self._chunk_size]
for i in range(0, len(value), self._chunk_size)
]
if len(chunks[-1]) == self._chunk_size:
self._buffer.seek(0)
self._buffer.truncate()
return chunks
else:
self._buffer.seek(0)
self._buffer.write(chunks[-1])
self._buffer.truncate()
return chunks[:-1]
else:
return []
def flush(self) -> list[bytes]:
value = self._buffer.getvalue()
self._buffer.seek(0)
self._buffer.truncate()
return [value] if value else []
class TextChunker:
"""
Handles returning text content in fixed-size chunks.
"""
def __init__(self, chunk_size: int | None = None) -> None:
self._buffer = io.StringIO()
self._chunk_size = chunk_size
def decode(self, content: str) -> list[str]:
if self._chunk_size is None:
return [content] if content else []
self._buffer.write(content)
if self._buffer.tell() >= self._chunk_size:
value = self._buffer.getvalue()
chunks = [
value[i : i + self._chunk_size]
for i in range(0, len(value), self._chunk_size)
]
if len(chunks[-1]) == self._chunk_size:
self._buffer.seek(0)
self._buffer.truncate()
return chunks
else:
self._buffer.seek(0)
self._buffer.write(chunks[-1])
self._buffer.truncate()
return chunks[:-1]
else:
return []
def flush(self) -> list[str]:
value = self._buffer.getvalue()
self._buffer.seek(0)
self._buffer.truncate()
return [value] if value else []
class TextDecoder:
"""
Handles incrementally decoding bytes into text
"""
def __init__(self, encoding: str = "utf-8") -> None:
self.decoder = codecs.getincrementaldecoder(encoding)(errors="replace")
def decode(self, data: bytes) -> str:
return self.decoder.decode(data)
def flush(self) -> str:
return self.decoder.decode(b"", True)
class LineDecoder:
"""
Handles incrementally reading lines from text.
Has the same behaviour as the stdllib splitlines,
but handling the input iteratively.
"""
def __init__(self) -> None:
self.buffer: list[str] = []
self.trailing_cr: bool = False
def decode(self, text: str) -> list[str]:
# See https://docs.python.org/3/library/stdtypes.html#str.splitlines
NEWLINE_CHARS = "\n\r\x0b\x0c\x1c\x1d\x1e\x85\u2028\u2029"
# We always push a trailing `\r` into the next decode iteration.
if self.trailing_cr:
text = "\r" + text
self.trailing_cr = False
if text.endswith("\r"):
self.trailing_cr = True
text = text[:-1]
if not text:
# NOTE: the edge case input of empty text doesn't occur in practice,
# because other httpx internals filter out this value
return [] # pragma: no cover
trailing_newline = text[-1] in NEWLINE_CHARS
lines = text.splitlines()
if len(lines) == 1 and not trailing_newline:
# No new lines, buffer the input and continue.
self.buffer.append(lines[0])
return []
if self.buffer:
# Include any existing buffer in the first portion of the
# splitlines result.
lines = ["".join(self.buffer) + lines[0]] + lines[1:]
self.buffer = []
if not trailing_newline:
# If the last segment of splitlines is not newline terminated,
# then drop it from our output and start a new buffer.
self.buffer = [lines.pop()]
return lines
def flush(self) -> list[str]:
if not self.buffer and not self.trailing_cr:
return []
lines = ["".join(self.buffer)]
self.buffer = []
self.trailing_cr = False
return lines
SUPPORTED_DECODERS = {
"identity": IdentityDecoder,
"gzip": GZipDecoder,
"deflate": DeflateDecoder,
"br": BrotliDecoder,
"zstd": ZStandardDecoder,
}
if brotli is None:
SUPPORTED_DECODERS.pop("br") # pragma: no cover
if zstd is None:
SUPPORTED_DECODERS.pop("zstd") # pragma: no cover
|