« prev ^ index » next coverage.py v7.2.2, created at 2023-03-26 06:10 +0000
1# -*- coding: utf-8 -*-
2# Copyright 2022 Google LLC
3#
4# Licensed under the Apache License, Version 2.0 (the "License");
5# you may not use this file except in compliance with the License.
6# You may obtain a copy of the License at
7#
8# http://www.apache.org/licenses/LICENSE-2.0
9#
10# Unless required by applicable law or agreed to in writing, software
11# distributed under the License is distributed on an "AS IS" BASIS,
12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13# See the License for the specific language governing permissions and
14# limitations under the License.
15#
16import warnings
17from typing import Callable, Dict, Optional, Sequence, Tuple, Union
19from google.api_core import grpc_helpers
20from google.api_core import gapic_v1
21import google.auth # type: ignore
22from google.auth import credentials as ga_credentials # type: ignore
23from google.auth.transport.grpc import SslCredentials # type: ignore
25import grpc # type: ignore
27from google.cloud.bigquery_storage_v1.types import storage
28from google.cloud.bigquery_storage_v1.types import stream
29from .base import BigQueryReadTransport, DEFAULT_CLIENT_INFO
32class BigQueryReadGrpcTransport(BigQueryReadTransport):
33 """gRPC backend transport for BigQueryRead.
35 BigQuery Read API.
36 The Read API can be used to read data from BigQuery.
38 This class defines the same methods as the primary client, so the
39 primary client can load the underlying transport implementation
40 and call it.
42 It sends protocol buffers over the wire using gRPC (which is built on
43 top of HTTP/2); the ``grpcio`` package must be installed.
44 """
46 _stubs: Dict[str, Callable]
48 def __init__(
49 self,
50 *,
51 host: str = "bigquerystorage.googleapis.com",
52 credentials: Optional[ga_credentials.Credentials] = None,
53 credentials_file: Optional[str] = None,
54 scopes: Optional[Sequence[str]] = None,
55 channel: Optional[grpc.Channel] = None,
56 api_mtls_endpoint: Optional[str] = None,
57 client_cert_source: Optional[Callable[[], Tuple[bytes, bytes]]] = None,
58 ssl_channel_credentials: Optional[grpc.ChannelCredentials] = None,
59 client_cert_source_for_mtls: Optional[Callable[[], Tuple[bytes, bytes]]] = None,
60 quota_project_id: Optional[str] = None,
61 client_info: gapic_v1.client_info.ClientInfo = DEFAULT_CLIENT_INFO,
62 always_use_jwt_access: Optional[bool] = False,
63 api_audience: Optional[str] = None,
64 ) -> None:
65 """Instantiate the transport.
67 Args:
68 host (Optional[str]):
69 The hostname to connect to.
70 credentials (Optional[google.auth.credentials.Credentials]): The
71 authorization credentials to attach to requests. These
72 credentials identify the application to the service; if none
73 are specified, the client will attempt to ascertain the
74 credentials from the environment.
75 This argument is ignored if ``channel`` is provided.
76 credentials_file (Optional[str]): A file with credentials that can
77 be loaded with :func:`google.auth.load_credentials_from_file`.
78 This argument is ignored if ``channel`` is provided.
79 scopes (Optional(Sequence[str])): A list of scopes. This argument is
80 ignored if ``channel`` is provided.
81 channel (Optional[grpc.Channel]): A ``Channel`` instance through
82 which to make calls.
83 api_mtls_endpoint (Optional[str]): Deprecated. The mutual TLS endpoint.
84 If provided, it overrides the ``host`` argument and tries to create
85 a mutual TLS channel with client SSL credentials from
86 ``client_cert_source`` or application default SSL credentials.
87 client_cert_source (Optional[Callable[[], Tuple[bytes, bytes]]]):
88 Deprecated. A callback to provide client SSL certificate bytes and
89 private key bytes, both in PEM format. It is ignored if
90 ``api_mtls_endpoint`` is None.
91 ssl_channel_credentials (grpc.ChannelCredentials): SSL credentials
92 for the grpc channel. It is ignored if ``channel`` is provided.
93 client_cert_source_for_mtls (Optional[Callable[[], Tuple[bytes, bytes]]]):
94 A callback to provide client certificate bytes and private key bytes,
95 both in PEM format. It is used to configure a mutual TLS channel. It is
96 ignored if ``channel`` or ``ssl_channel_credentials`` is provided.
97 quota_project_id (Optional[str]): An optional project to use for billing
98 and quota.
99 client_info (google.api_core.gapic_v1.client_info.ClientInfo):
100 The client info used to send a user-agent string along with
101 API requests. If ``None``, then default info will be used.
102 Generally, you only need to set this if you're developing
103 your own client library.
104 always_use_jwt_access (Optional[bool]): Whether self signed JWT should
105 be used for service account credentials.
107 Raises:
108 google.auth.exceptions.MutualTLSChannelError: If mutual TLS transport
109 creation failed for any reason.
110 google.api_core.exceptions.DuplicateCredentialArgs: If both ``credentials``
111 and ``credentials_file`` are passed.
112 """
113 self._grpc_channel = None
114 self._ssl_channel_credentials = ssl_channel_credentials
115 self._stubs: Dict[str, Callable] = {}
117 if api_mtls_endpoint:
118 warnings.warn("api_mtls_endpoint is deprecated", DeprecationWarning)
119 if client_cert_source:
120 warnings.warn("client_cert_source is deprecated", DeprecationWarning)
122 if channel:
123 # Ignore credentials if a channel was passed.
124 credentials = False
125 # If a channel was explicitly provided, set it.
126 self._grpc_channel = channel
127 self._ssl_channel_credentials = None
129 else:
130 if api_mtls_endpoint:
131 host = api_mtls_endpoint
133 # Create SSL credentials with client_cert_source or application
134 # default SSL credentials.
135 if client_cert_source:
136 cert, key = client_cert_source()
137 self._ssl_channel_credentials = grpc.ssl_channel_credentials(
138 certificate_chain=cert, private_key=key
139 )
140 else:
141 self._ssl_channel_credentials = SslCredentials().ssl_credentials
143 else:
144 if client_cert_source_for_mtls and not ssl_channel_credentials:
145 cert, key = client_cert_source_for_mtls()
146 self._ssl_channel_credentials = grpc.ssl_channel_credentials(
147 certificate_chain=cert, private_key=key
148 )
150 # The base transport sets the host, credentials and scopes
151 super().__init__(
152 host=host,
153 credentials=credentials,
154 credentials_file=credentials_file,
155 scopes=scopes,
156 quota_project_id=quota_project_id,
157 client_info=client_info,
158 always_use_jwt_access=always_use_jwt_access,
159 api_audience=api_audience,
160 )
162 if not self._grpc_channel:
163 self._grpc_channel = type(self).create_channel(
164 self._host,
165 # use the credentials which are saved
166 credentials=self._credentials,
167 # Set ``credentials_file`` to ``None`` here as
168 # the credentials that we saved earlier should be used.
169 credentials_file=None,
170 scopes=self._scopes,
171 ssl_credentials=self._ssl_channel_credentials,
172 quota_project_id=quota_project_id,
173 options=[
174 ("grpc.max_send_message_length", -1),
175 ("grpc.max_receive_message_length", -1),
176 ],
177 )
179 # Wrap messages. This must be done after self._grpc_channel exists
180 self._prep_wrapped_messages(client_info)
182 @classmethod
183 def create_channel(
184 cls,
185 host: str = "bigquerystorage.googleapis.com",
186 credentials: Optional[ga_credentials.Credentials] = None,
187 credentials_file: Optional[str] = None,
188 scopes: Optional[Sequence[str]] = None,
189 quota_project_id: Optional[str] = None,
190 **kwargs,
191 ) -> grpc.Channel:
192 """Create and return a gRPC channel object.
193 Args:
194 host (Optional[str]): The host for the channel to use.
195 credentials (Optional[~.Credentials]): The
196 authorization credentials to attach to requests. These
197 credentials identify this application to the service. If
198 none are specified, the client will attempt to ascertain
199 the credentials from the environment.
200 credentials_file (Optional[str]): A file with credentials that can
201 be loaded with :func:`google.auth.load_credentials_from_file`.
202 This argument is mutually exclusive with credentials.
203 scopes (Optional[Sequence[str]]): A optional list of scopes needed for this
204 service. These are only used when credentials are not specified and
205 are passed to :func:`google.auth.default`.
206 quota_project_id (Optional[str]): An optional project to use for billing
207 and quota.
208 kwargs (Optional[dict]): Keyword arguments, which are passed to the
209 channel creation.
210 Returns:
211 grpc.Channel: A gRPC channel object.
213 Raises:
214 google.api_core.exceptions.DuplicateCredentialArgs: If both ``credentials``
215 and ``credentials_file`` are passed.
216 """
218 return grpc_helpers.create_channel(
219 host,
220 credentials=credentials,
221 credentials_file=credentials_file,
222 quota_project_id=quota_project_id,
223 default_scopes=cls.AUTH_SCOPES,
224 scopes=scopes,
225 default_host=cls.DEFAULT_HOST,
226 **kwargs,
227 )
229 @property
230 def grpc_channel(self) -> grpc.Channel:
231 """Return the channel designed to connect to this service."""
232 return self._grpc_channel
234 @property
235 def create_read_session(
236 self,
237 ) -> Callable[[storage.CreateReadSessionRequest], stream.ReadSession]:
238 r"""Return a callable for the create read session method over gRPC.
240 Creates a new read session. A read session divides
241 the contents of a BigQuery table into one or more
242 streams, which can then be used to read data from the
243 table. The read session also specifies properties of the
244 data to be read, such as a list of columns or a
245 push-down filter describing the rows to be returned.
247 A particular row can be read by at most one stream. When
248 the caller has reached the end of each stream in the
249 session, then all the data in the table has been read.
251 Data is assigned to each stream such that roughly the
252 same number of rows can be read from each stream.
253 Because the server-side unit for assigning data is
254 collections of rows, the API does not guarantee that
255 each stream will return the same number or rows.
256 Additionally, the limits are enforced based on the
257 number of pre-filtered rows, so some filters can lead to
258 lopsided assignments.
260 Read sessions automatically expire 6 hours after they
261 are created and do not require manual clean-up by the
262 caller.
264 Returns:
265 Callable[[~.CreateReadSessionRequest],
266 ~.ReadSession]:
267 A function that, when called, will call the underlying RPC
268 on the server.
269 """
270 # Generate a "stub function" on-the-fly which will actually make
271 # the request.
272 # gRPC handles serialization and deserialization, so we just need
273 # to pass in the functions for each.
274 if "create_read_session" not in self._stubs:
275 self._stubs["create_read_session"] = self.grpc_channel.unary_unary(
276 "/google.cloud.bigquery.storage.v1.BigQueryRead/CreateReadSession",
277 request_serializer=storage.CreateReadSessionRequest.serialize,
278 response_deserializer=stream.ReadSession.deserialize,
279 )
280 return self._stubs["create_read_session"]
282 @property
283 def read_rows(
284 self,
285 ) -> Callable[[storage.ReadRowsRequest], storage.ReadRowsResponse]:
286 r"""Return a callable for the read rows method over gRPC.
288 Reads rows from the stream in the format prescribed
289 by the ReadSession. Each response contains one or more
290 table rows, up to a maximum of 100 MiB per response;
291 read requests which attempt to read individual rows
292 larger than 100 MiB will fail.
294 Each request also returns a set of stream statistics
295 reflecting the current state of the stream.
297 Returns:
298 Callable[[~.ReadRowsRequest],
299 ~.ReadRowsResponse]:
300 A function that, when called, will call the underlying RPC
301 on the server.
302 """
303 # Generate a "stub function" on-the-fly which will actually make
304 # the request.
305 # gRPC handles serialization and deserialization, so we just need
306 # to pass in the functions for each.
307 if "read_rows" not in self._stubs:
308 self._stubs["read_rows"] = self.grpc_channel.unary_stream(
309 "/google.cloud.bigquery.storage.v1.BigQueryRead/ReadRows",
310 request_serializer=storage.ReadRowsRequest.serialize,
311 response_deserializer=storage.ReadRowsResponse.deserialize,
312 )
313 return self._stubs["read_rows"]
315 @property
316 def split_read_stream(
317 self,
318 ) -> Callable[[storage.SplitReadStreamRequest], storage.SplitReadStreamResponse]:
319 r"""Return a callable for the split read stream method over gRPC.
321 Splits a given ``ReadStream`` into two ``ReadStream`` objects.
322 These ``ReadStream`` objects are referred to as the primary and
323 the residual streams of the split. The original ``ReadStream``
324 can still be read from in the same manner as before. Both of the
325 returned ``ReadStream`` objects can also be read from, and the
326 rows returned by both child streams will be the same as the rows
327 read from the original stream.
329 Moreover, the two child streams will be allocated back-to-back
330 in the original ``ReadStream``. Concretely, it is guaranteed
331 that for streams original, primary, and residual, that
332 original[0-j] = primary[0-j] and original[j-n] = residual[0-m]
333 once the streams have been read to completion.
335 Returns:
336 Callable[[~.SplitReadStreamRequest],
337 ~.SplitReadStreamResponse]:
338 A function that, when called, will call the underlying RPC
339 on the server.
340 """
341 # Generate a "stub function" on-the-fly which will actually make
342 # the request.
343 # gRPC handles serialization and deserialization, so we just need
344 # to pass in the functions for each.
345 if "split_read_stream" not in self._stubs:
346 self._stubs["split_read_stream"] = self.grpc_channel.unary_unary(
347 "/google.cloud.bigquery.storage.v1.BigQueryRead/SplitReadStream",
348 request_serializer=storage.SplitReadStreamRequest.serialize,
349 response_deserializer=storage.SplitReadStreamResponse.deserialize,
350 )
351 return self._stubs["split_read_stream"]
353 def close(self):
354 self.grpc_channel.close()
356 @property
357 def kind(self) -> str:
358 return "grpc"
361__all__ = ("BigQueryReadGrpcTransport",)