-
Notifications
You must be signed in to change notification settings - Fork 13
/
core.py
282 lines (244 loc) · 9.78 KB
/
core.py
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
import base64
import hashlib
import hmac
import logging
from binascii import hexlify
from datetime import datetime
from functools import reduce
from typing import TYPE_CHECKING, Any, Dict, Generator, List, Literal, Optional, Tuple
from urllib.parse import quote as url_quote
from httpx import URL, AsyncClient, Auth, Request, Response
from ._utils import get_config_attr, pretty_xml, utcnow
if TYPE_CHECKING:
from ._types import BaseConfigProtocol
__all__ = 'AwsClient', 'RequestError'
logger = logging.getLogger('aioaws.core')
_AWS_AUTH_REQUEST = 'aws4_request'
_CONTENT_TYPE = 'application/x-www-form-urlencoded'
_AUTH_ALGORITHM = 'AWS4-HMAC-SHA256'
class AwsClient:
"""
HTTP client for AWS with authentication
"""
def __init__(self, client: AsyncClient, config: 'BaseConfigProtocol', service: Literal['s3', 'ses']):
self.client = client
self.aws_access_key = get_config_attr(config, 'aws_access_key')
self.aws_secret_key = get_config_attr(config, 'aws_secret_key')
self.service = service
self.region = get_config_attr(config, 'aws_region')
try:
self.host = get_config_attr(config, 'aws_host')
except TypeError:
if self.service == 'ses':
self.host = f'email.{self.region}.amazonaws.com'
else:
assert self.service == 's3', self.service
bucket = get_config_attr(config, 'aws_s3_bucket')
if '.' in bucket:
# assumes the bucket is a domain and is already as a CNAME record for S3
self.host = bucket
else:
# see https://docs.aws.amazon.com/AmazonS3/latest/userguide/access-bucket-intro.html
self.host = f'{bucket}.s3.{self.region}.amazonaws.com'
self.schema = 'https'
self._auth = AWSv4Auth(
aws_secret_key=self.aws_secret_key,
aws_access_key=self.aws_access_key,
region=self.region,
service=self.service,
)
@property
def endpoint(self) -> str:
return f'{self.schema}://{self.host}'
async def get(self, path: str = '', *, params: Optional[Dict[str, Any]] = None) -> Response:
return await self.request('GET', path=path, params=params)
async def raw_post(
self,
url: str,
*,
expected_status: int,
params: Optional[Dict[str, Any]] = None,
data: Optional[Dict[str, str]] = None,
files: Optional[Dict[str, bytes]] = None,
) -> Response:
r = await self.client.post(url, params=params, data=data, files=files)
if r.status_code == expected_status:
return r
else:
# from ._utils import pretty_response
# pretty_response(r)
raise RequestError(r)
async def post(
self,
path: str = '',
*,
params: Optional[Dict[str, Any]] = None,
data: Optional[bytes] = None,
content_type: Optional[str] = None,
) -> Response:
return await self.request('POST', path=path, params=params, data=data, content_type=content_type)
async def request(
self,
method: Literal['GET', 'POST'],
*,
path: str,
params: Optional[Dict[str, Any]],
data: Optional[bytes] = None,
content_type: Optional[str] = None,
) -> Response:
url = URL(f'{self.endpoint}{path}', params=[(k, v) for k, v in sorted((params or {}).items())])
r = await self.client.request(
method,
url,
content=data,
headers=self._auth.auth_headers(method, url, data=data, content_type=content_type),
)
if r.status_code != 200:
# from ._utils import pretty_response
# pretty_response(r)
raise RequestError(r)
return r
def add_signed_download_params(self, method: Literal['GET', 'POST'], url: URL, expires: int = 86400) -> URL:
assert expires >= 1, f'expires must be greater than or equal to 1, not {expires}'
assert expires <= 604800, f'expires must be less than or equal to 604800, not {expires}'
now = utcnow()
url = url.copy_merge_params(
{
'X-Amz-Algorithm': _AUTH_ALGORITHM,
'X-Amz-Credential': self._auth.aws4_credential(now),
'X-Amz-Date': _aws4_x_amz_date(now),
'X-Amz-Expires': str(expires),
'X-Amz-SignedHeaders': 'host',
}
)
_, signature = self._auth.aws4_signature(now, method, url, {'host': self.host}, 'UNSIGNED-PAYLOAD')
return url.copy_add_param('X-Amz-Signature', signature)
def upload_extra_conditions(self, dt: datetime) -> List[Dict[str, str]]:
return [
{'x-amz-credential': self._auth.aws4_credential(dt)},
{'x-amz-algorithm': _AUTH_ALGORITHM},
{'x-amz-date': _aws4_x_amz_date(dt)},
]
def signed_upload_fields(self, dt: datetime, string_to_sign: str) -> Dict[str, str]:
return {
'X-Amz-Algorithm': _AUTH_ALGORITHM,
'X-Amz-Credential': self._auth.aws4_credential(dt),
'X-Amz-Date': _aws4_x_amz_date(dt),
'X-Amz-Signature': self._auth.aws4_sign_string(string_to_sign, dt),
}
class AWSv4Auth:
def __init__(
self,
aws_secret_key: str,
aws_access_key: str,
region: str,
service: str,
) -> None:
self.aws_secret_key = aws_secret_key
self.aws_access_key = aws_access_key
self.region = region
self.service = service
def auth_headers(
self,
method: Literal['GET', 'POST'],
url: URL,
*,
data: Optional[bytes] = None,
content_type: Optional[str] = None,
) -> Dict[str, str]:
now = utcnow()
data = data or b''
content_type = content_type or _CONTENT_TYPE
# WARNING! order is important here, headers need to be in alphabetical order
headers = {
'content-md5': base64.b64encode(hashlib.md5(data).digest()).decode(),
'content-type': content_type,
'host': url.host,
'x-amz-date': _aws4_x_amz_date(now),
}
payload_sha256_hash = hashlib.sha256(data).hexdigest()
signed_headers, signature = self.aws4_signature(now, method, url, headers, payload_sha256_hash)
credential = self.aws4_credential(now)
authorization_header = (
f'{_AUTH_ALGORITHM} Credential={credential},SignedHeaders={signed_headers},Signature={signature}'
)
headers.update({'authorization': authorization_header, 'x-amz-content-sha256': payload_sha256_hash})
return headers
def aws4_signature(
self, dt: datetime, method: Literal['GET', 'POST'], url: URL, headers: Dict[str, str], payload_hash: str
) -> Tuple[str, str]:
header_keys = sorted(headers)
signed_headers = ';'.join(header_keys)
canonical_request_parts = (
method,
url_quote(url.path),
url.query.decode(),
''.join(f'{k}:{headers[k]}\n' for k in header_keys),
signed_headers,
payload_hash,
)
canonical_request = '\n'.join(canonical_request_parts)
string_to_sign_parts = (
_AUTH_ALGORITHM,
_aws4_x_amz_date(dt),
self._aws4_scope(dt),
hashlib.sha256(canonical_request.encode()).hexdigest(),
)
string_to_sign = '\n'.join(string_to_sign_parts)
return signed_headers, self.aws4_sign_string(string_to_sign, dt)
def aws4_sign_string(self, string_to_sign: str, dt: datetime) -> str:
key_parts = (
b'AWS4' + self.aws_secret_key.encode(),
_aws4_date_stamp(dt),
self.region,
self.service,
_AWS_AUTH_REQUEST,
string_to_sign,
)
signature_bytes: bytes = reduce(_aws4_reduce_signature, key_parts) # type: ignore
return hexlify(signature_bytes).decode()
def _aws4_scope(self, dt: datetime) -> str:
return f'{_aws4_date_stamp(dt)}/{self.region}/{self.service}/{_AWS_AUTH_REQUEST}'
def aws4_credential(self, dt: datetime) -> str:
return f'{self.aws_access_key}/{self._aws4_scope(dt)}'
class AWSV4AuthFlow(Auth):
def __init__(
self,
aws_secret_key: str,
aws_access_key: str,
region: str,
service: str,
) -> None:
self._authorizer = AWSv4Auth(
aws_secret_key=aws_secret_key,
aws_access_key=aws_access_key,
region=region,
service=service,
)
def auth_flow(self, request: Request) -> Generator[Request, Response, None]:
auth_headers = self._authorizer.auth_headers(
method=request.method.upper(), # type: ignore
url=request.url,
data=request.content,
content_type=request.headers.get('Content-Type'),
)
request.headers.update(auth_headers)
yield request
def _aws4_date_stamp(dt: datetime) -> str:
return dt.strftime('%Y%m%d')
def _aws4_x_amz_date(dt: datetime) -> str:
return dt.strftime('%Y%m%dT%H%M%SZ')
def _aws4_reduce_signature(key: bytes, msg: str) -> bytes:
return hmac.new(key, msg.encode(), hashlib.sha256).digest()
class RequestError(RuntimeError):
def __init__(self, r: Response):
error_msg = f'unexpected response from {r.request.method} "{r.request.url}": {r.status_code}'
super().__init__(error_msg)
self.response = r
self.status = r.status_code
def __str__(self) -> str:
if self.response.headers.get('content-type') == 'application/xml':
text = pretty_xml(self.response.content)
else:
text = self.response.text
return f'{self.args[0]}, response:\n{text}'