import copy
import json
import zlib
from io import BytesIO
from urllib.parse import urlencode, urlparse, urlunparse
from .util import CaseInsensitiveDict
[docs]
def replace_query_parameters(request, replacements):
"""Replace query parameters in request according to replacements.
The replacements should be a list of (key, value) pairs where the value can be any of:
1. A simple replacement string value.
2. None to remove the given header.
3. A callable which accepts (key, value, request) and returns a string
value or None.
"""
query = request.query
new_query = []
replacements = dict(replacements)
for k, ov in query:
if k not in replacements:
new_query.append((k, ov))
else:
rv = replacements[k]
if callable(rv):
rv = rv(key=k, value=ov, request=request)
if rv is not None:
new_query.append((k, rv))
uri_parts = list(urlparse(request.uri))
uri_parts[4] = urlencode(new_query)
request.uri = urlunparse(uri_parts)
return request
[docs]
def remove_query_parameters(request, query_parameters_to_remove):
"""
Wrap replace_query_parameters() for API backward compatibility.
"""
replacements = [(k, None) for k in query_parameters_to_remove]
return replace_query_parameters(request, replacements)
[docs]
def replace_post_data_parameters(request, replacements):
"""Replace post data in request--either form data or json--according to replacements.
The replacements should be a list of (key, value) pairs where the value can be any of:
1. A simple replacement string value.
2. None to remove the given header.
3. A callable which accepts (key, value, request) and returns a string
value or None.
"""
if not request.body:
# Nothing to replace
return request
replacements = dict(replacements)
if request.method == "POST" and not isinstance(request.body, BytesIO):
if isinstance(request.body, dict):
new_body = request.body.copy()
for k, rv in replacements.items():
if k in new_body:
ov = new_body.pop(k)
if callable(rv):
rv = rv(key=k, value=ov, request=request)
if rv is not None:
new_body[k] = rv
request.body = new_body
elif request.headers.get("Content-Type") == "application/json":
json_data = json.loads(request.body)
for k, rv in replacements.items():
if k in json_data:
ov = json_data.pop(k)
if callable(rv):
rv = rv(key=k, value=ov, request=request)
if rv is not None:
json_data[k] = rv
request.body = json.dumps(json_data).encode("utf-8")
else:
if isinstance(request.body, str):
request.body = request.body.encode("utf-8")
splits = [p.partition(b"=") for p in request.body.split(b"&")]
new_splits = []
for k, sep, ov in splits:
if sep is None:
new_splits.append((k, sep, ov))
else:
rk = k.decode("utf-8")
if rk not in replacements:
new_splits.append((k, sep, ov))
else:
rv = replacements[rk]
if callable(rv):
rv = rv(key=rk, value=ov.decode("utf-8"), request=request)
if rv is not None:
new_splits.append((k, sep, rv.encode("utf-8")))
request.body = b"&".join(k if sep is None else b"".join([k, sep, v]) for k, sep, v in new_splits)
return request
[docs]
def remove_post_data_parameters(request, post_data_parameters_to_remove):
"""
Wrap replace_post_data_parameters() for API backward compatibility.
"""
replacements = [(k, None) for k in post_data_parameters_to_remove]
return replace_post_data_parameters(request, replacements)
[docs]
def decode_response(response):
"""
If the response is compressed with gzip or deflate:
1. decompress the response body
2. delete the content-encoding header
3. update content-length header to decompressed length
"""
def is_compressed(headers):
encoding = headers.get("content-encoding", [])
return encoding and encoding[0] in ("gzip", "deflate")
def decompress_body(body, encoding):
"""Returns decompressed body according to encoding using zlib.
to (de-)compress gzip format, use wbits = zlib.MAX_WBITS | 16
"""
if not body:
return ""
if encoding == "gzip":
try:
return zlib.decompress(body, zlib.MAX_WBITS | 16)
except zlib.error:
return body # assumes that the data was already decompressed
else: # encoding == 'deflate'
try:
return zlib.decompress(body)
except zlib.error:
return body # assumes that the data was already decompressed
# Deepcopy here in case `headers` contain objects that could
# be mutated by a shallow copy and corrupt the real response.
response = copy.deepcopy(response)
headers = CaseInsensitiveDict(response["headers"])
if is_compressed(headers):
encoding = headers["content-encoding"][0]
headers["content-encoding"].remove(encoding)
if not headers["content-encoding"]:
del headers["content-encoding"]
new_body = decompress_body(response["body"]["string"], encoding)
response["body"]["string"] = new_body
headers["content-length"] = [str(len(new_body))]
response["headers"] = dict(headers)
return response