client.py

# -*- coding: utf-8 -*-

# Copyright (C) 2019  Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

from collections import OrderedDict
from typing import Dict, Sequence, Tuple, Type, Union
import pkg_resources

import google.api_core.client_options as ClientOptions # type: ignore
from google.api_core import exceptions                 # type: ignore
from google.api_core import gapic_v1                   # type: ignore
from google.api_core import retry as retries           # type: ignore
from google.auth import credentials                    # type: ignore
from google.oauth2 import service_account              # type: ignore

from google.api_core import operation
from google.protobuf import duration_pb2 as duration  # type: ignore
from google.protobuf import timestamp_pb2 as timestamp  # type: ignore
from google.rpc import status_pb2 as status  # type: ignore
from google.showcase_v1beta1.services.echo import pagers
from google.showcase_v1beta1.types import echo
from google.showcase_v1beta1.types import echo as gs_echo

from .transports.base import EchoTransport
from .transports.grpc import EchoGrpcTransport


class EchoClientMeta(type):
    """Metaclass for the Echo client.

    This provides class-level methods for building and retrieving
    support objects (e.g. transport) without polluting the client instance
    objects.
    """
    _transport_registry = OrderedDict()  # type: Dict[str, Type[EchoTransport]]
    _transport_registry['grpc'] = EchoGrpcTransport

    def get_transport_class(cls,
            label: str = None,
            ) -> Type[EchoTransport]:
        """Return an appropriate transport class.

        Args:
            label: The name of the desired transport. If none is
                provided, then the first transport in the registry is used.

        Returns:
            The transport class to use.
        """
        # If a specific transport is requested, return that one.
        if label:
            return cls._transport_registry[label]

        # No transport is requested; return the default (that is, the first one
        # in the dictionary).
        return next(iter(cls._transport_registry.values()))


class EchoClient(metaclass=EchoClientMeta):
    """This service is used showcase the four main types of rpcs -
    unary, server side streaming, client side streaming, and
    bidirectional streaming. This service also exposes methods that
    explicitly implement server delay, and paginated calls. Set the
    'showcase-trailer' metadata key on any method to have the values
    echoed in the response trailers.
    """

    DEFAULT_OPTIONS = ClientOptions.ClientOptions(api_endpoint='localhost:7469')

    @classmethod
    def from_service_account_file(cls, filename: str, *args, **kwargs):
        """Creates an instance of this client using the provided credentials
        file.

        Args:
            filename (str): The path to the service account private key json
                file.
            args: Additional arguments to pass to the constructor.
            kwargs: Additional arguments to pass to the constructor.

        Returns:
            {@api.name}: The constructed client.
        """
        credentials = service_account.Credentials.from_service_account_file(
            filename)
        kwargs['credentials'] = credentials
        return cls(*args, **kwargs)

    from_service_account_json = from_service_account_file

    def __init__(self, *,
            credentials: credentials.Credentials = None,
            transport: Union[str, EchoTransport] = None,
            client_options: ClientOptions = DEFAULT_OPTIONS,
            ) -> None:
        """Instantiate the echo client.

        Args:
            credentials (Optional[google.auth.credentials.Credentials]): The
                authorization credentials to attach to requests. These
                credentials identify the application to the service; if none
                are specified, the client will attempt to ascertain the
                credentials from the environment.
            transport (Union[str, ~.EchoTransport]): The
                transport to use. If set to None, a transport is chosen
                automatically.
            client_options (ClientOptions): Custom options for the client.
        """
        if isinstance(client_options, dict):
            client_options = ClientOptions.from_dict(client_options)

        # Save or instantiate the transport.
        # Ordinarily, we provide the transport, but allowing a custom transport
        # instance provides an extensibility point for unusual situations.
        if isinstance(transport, EchoTransport):
            if credentials:
                raise ValueError('When providing a transport instance, '
                                 'provide its credentials directly.')
            self._transport = transport
        else:
            Transport = type(self).get_transport_class(transport)
            self._transport = Transport(
                credentials=credentials,
                host=client_options.api_endpoint or 'localhost:7469',
            )

    def echo(self,
            request: gs_echo.EchoRequest = None,
            *,
            retry: retries.Retry = gapic_v1.method.DEFAULT,
            timeout: float = None,
            metadata: Sequence[Tuple[str, str]] = (),
            ) -> gs_echo.EchoResponse:
        r"""This method simply echos the request. This method is
        showcases unary rpcs.

        Args:
            request (:class:`~.gs_echo.EchoRequest`):
                The request object. The request message used for the
                Echo, Collect and Chat methods. If content is set in
                this message then the request will succeed. If status is
                set in  this message then the status will be returned as
                an error.
            retry (google.api_core.retry.Retry): Designation of what errors, if any,
                should be retried.
            timeout (float): The timeout for this request.
            metadata (Sequence[Tuple[str, str]]): Strings which should be
                sent along with the request as metadata.

        Returns:
            ~.gs_echo.EchoResponse:
                The response message for the Echo
                methods.

        """
        # Create or coerce a protobuf request object.
        request = gs_echo.EchoRequest(request)

        # Wrap the RPC method; this adds retry and timeout information,
        # and friendly error handling.
        rpc = gapic_v1.method.wrap_method(
            self._transport.echo,
            default_timeout=None,
            client_info=_client_info,
        )

        # Send the request.
        response = rpc(
            request,
            retry=retry,
            timeout=timeout,
            metadata=metadata,
        )

        # Done; return the response.
        return response

    def expand(self,
            request: gs_echo.ExpandRequest = None,
            *,
            content: str = None,
            error: status.Status = None,
            retry: retries.Retry = gapic_v1.method.DEFAULT,
            timeout: float = None,
            metadata: Sequence[Tuple[str, str]] = (),
            ) -> gs_echo.EchoResponse:
        r"""This method split the given content into words and
        will pass each word back through the stream. This method
        showcases server-side streaming rpcs.

        Args:
            request (:class:`~.gs_echo.ExpandRequest`):
                The request object. The request message for the Expand
                method.
            content (:class:`str`):
                The content that will be split into
                words and returned on the stream.
                This corresponds to the ``content`` field
                on the ``request`` instance; if ``request`` is provided, this
                should not be set.
            error (:class:`~.status.Status`):
                The error that is thrown after all
                words are sent on the stream.
                This corresponds to the ``error`` field
                on the ``request`` instance; if ``request`` is provided, this
                should not be set.
            retry (google.api_core.retry.Retry): Designation of what errors, if any,
                should be retried.
            timeout (float): The timeout for this request.
            metadata (Sequence[Tuple[str, str]]): Strings which should be
                sent along with the request as metadata.

        Returns:
            ~.gs_echo.EchoResponse:
                The response message for the Echo
                methods.

        """
        # Create or coerce a protobuf request object.
        # Sanity check: If we got a request object, we should *not* have
        # gotten any keyword arguments that map to the request.
        if request is not None and any([content, error]):
            raise ValueError('If the `request` argument is set, then none of '
                             'the individual field arguments should be set.')

        # If we have keyword arguments corresponding to fields on the
        # request, apply these.
        request = gs_echo.ExpandRequest(request)
        if content is not None:
            request.content = content
        if error is not None:
            request.error = error

        # Wrap the RPC method; this adds retry and timeout information,
        # and friendly error handling.
        rpc = gapic_v1.method.wrap_method(
            self._transport.expand,
            default_timeout=None,
            client_info=_client_info,
        )

        # Send the request.
        response = rpc(
            request,
            retry=retry,
            timeout=timeout,
            metadata=metadata,
        )

        # Done; return the response.
        return response

    def collect(self,
            request: gs_echo.EchoRequest = None,
            *,
            retry: retries.Retry = gapic_v1.method.DEFAULT,
            timeout: float = None,
            metadata: Sequence[Tuple[str, str]] = (),
            ) -> gs_echo.EchoResponse:
        r"""This method will collect the words given to it. When
        the stream is closed by the client, this method will
        return the a concatenation of the strings passed to it.
        This method showcases client-side streaming rpcs.

        Args:
            request (:class:`~.gs_echo.EchoRequest`):
                The request object. The request message used for the
                Echo, Collect and Chat methods. If content is set in
                this message then the request will succeed. If status is
                set in  this message then the status will be returned as
                an error.
            retry (google.api_core.retry.Retry): Designation of what errors, if any,
                should be retried.
            timeout (float): The timeout for this request.
            metadata (Sequence[Tuple[str, str]]): Strings which should be
                sent along with the request as metadata.

        Returns:
            ~.gs_echo.EchoResponse:
                The response message for the Echo
                methods.

        """
        # Create or coerce a protobuf request object.
        request = gs_echo.EchoRequest(request)

        # Wrap the RPC method; this adds retry and timeout information,
        # and friendly error handling.
        rpc = gapic_v1.method.wrap_method(
            self._transport.collect,
            default_timeout=None,
            client_info=_client_info,
        )

        # Send the request.
        response = rpc(
            request,
            retry=retry,
            timeout=timeout,
            metadata=metadata,
        )

        # Done; return the response.
        return response

    def chat(self,
            request: gs_echo.EchoRequest = None,
            *,
            retry: retries.Retry = gapic_v1.method.DEFAULT,
            timeout: float = None,
            metadata: Sequence[Tuple[str, str]] = (),
            ) -> gs_echo.EchoResponse:
        r"""This method, upon receiving a request on the stream,
        the same content will be passed  back on the stream.
        This method showcases bidirectional streaming rpcs.

        Args:
            request (:class:`~.gs_echo.EchoRequest`):
                The request object. The request message used for the
                Echo, Collect and Chat methods. If content is set in
                this message then the request will succeed. If status is
                set in  this message then the status will be returned as
                an error.
            retry (google.api_core.retry.Retry): Designation of what errors, if any,
                should be retried.
            timeout (float): The timeout for this request.
            metadata (Sequence[Tuple[str, str]]): Strings which should be
                sent along with the request as metadata.

        Returns:
            ~.gs_echo.EchoResponse:
                The response message for the Echo
                methods.

        """
        # Create or coerce a protobuf request object.
        request = gs_echo.EchoRequest(request)

        # Wrap the RPC method; this adds retry and timeout information,
        # and friendly error handling.
        rpc = gapic_v1.method.wrap_method(
            self._transport.chat,
            default_timeout=None,
            client_info=_client_info,
        )

        # Send the request.
        response = rpc(
            request,
            retry=retry,
            timeout=timeout,
            metadata=metadata,
        )

        # Done; return the response.
        return response

    def paged_expand(self,
            request: gs_echo.PagedExpandRequest = None,
            *,
            retry: retries.Retry = gapic_v1.method.DEFAULT,
            timeout: float = None,
            metadata: Sequence[Tuple[str, str]] = (),
            ) -> pagers.PagedExpandPager:
        r"""This is similar to the Expand method but instead of
        returning a stream of expanded words, this method
        returns a paged list of expanded words.

        Args:
            request (:class:`~.gs_echo.PagedExpandRequest`):
                The request object. The request for the PagedExpand
                method.
            retry (google.api_core.retry.Retry): Designation of what errors, if any,
                should be retried.
            timeout (float): The timeout for this request.
            metadata (Sequence[Tuple[str, str]]): Strings which should be
                sent along with the request as metadata.

        Returns:
            ~.pagers.PagedExpandPager:
                The response for the PagedExpand
                method.
                Iterating over this object will yield
                results and resolve additional pages
                automatically.

        """
        # Create or coerce a protobuf request object.
        request = gs_echo.PagedExpandRequest(request)

        # Wrap the RPC method; this adds retry and timeout information,
        # and friendly error handling.
        rpc = gapic_v1.method.wrap_method(
            self._transport.paged_expand,
            default_timeout=None,
            client_info=_client_info,
        )

        # Send the request.
        response = rpc(
            request,
            retry=retry,
            timeout=timeout,
            metadata=metadata,
        )

        # This method is paged; wrap the response in a pager, which provides
        # an `__iter__` convenience method.
        response = pagers.PagedExpandPager(
            method=rpc,
            request=request,
            response=response,
        )

        # Done; return the response.
        return response

    def wait(self,
            request: gs_echo.WaitRequest = None,
            *,
            retry: retries.Retry = gapic_v1.method.DEFAULT,
            timeout: float = None,
            metadata: Sequence[Tuple[str, str]] = (),
            ) -> operation.Operation:
        r"""This method will wait the requested amount of and
        then return. This method showcases how a client handles
        a request timing out.

        Args:
            request (:class:`~.gs_echo.WaitRequest`):
                The request object. The request for Wait method.
            retry (google.api_core.retry.Retry): Designation of what errors, if any,
                should be retried.
            timeout (float): The timeout for this request.
            metadata (Sequence[Tuple[str, str]]): Strings which should be
                sent along with the request as metadata.

        Returns:
            ~.operation.Operation:
                An object representing a long-running operation.

                The result type for the operation will be
                :class:``~.echo.WaitResponse``: The result of the Wait
                operation.

        """
        # Create or coerce a protobuf request object.
        request = gs_echo.WaitRequest(request)

        # Wrap the RPC method; this adds retry and timeout information,
        # and friendly error handling.
        rpc = gapic_v1.method.wrap_method(
            self._transport.wait,
            default_timeout=None,
            client_info=_client_info,
        )

        # Send the request.
        response = rpc(
            request,
            retry=retry,
            timeout=timeout,
            metadata=metadata,
        )

        # Wrap the response in an operation future.
        response = operation.from_gapic(
            response,
            self._transport.operations_client,
            echo.WaitResponse,
            metadata_type=echo.WaitMetadata,
        )

        # Done; return the response.
        return response

    def block(self,
            request: gs_echo.BlockRequest = None,
            *,
            retry: retries.Retry = gapic_v1.method.DEFAULT,
            timeout: float = None,
            metadata: Sequence[Tuple[str, str]] = (),
            ) -> gs_echo.BlockResponse:
        r"""This method will block (wait) for the requested
        amount of time  and then return the response or error.
        This method showcases how a client handles delays or
        retries.

        Args:
            request (:class:`~.gs_echo.BlockRequest`):
                The request object. The request for Block method.
            retry (google.api_core.retry.Retry): Designation of what errors, if any,
                should be retried.
            timeout (float): The timeout for this request.
            metadata (Sequence[Tuple[str, str]]): Strings which should be
                sent along with the request as metadata.

        Returns:
            ~.gs_echo.BlockResponse:
                The response for Block method.
        """
        # Create or coerce a protobuf request object.
        request = gs_echo.BlockRequest(request)

        # Wrap the RPC method; this adds retry and timeout information,
        # and friendly error handling.
        rpc = gapic_v1.method.wrap_method(
            self._transport.block,
            default_timeout=None,
            client_info=_client_info,
        )

        # Send the request.
        response = rpc(
            request,
            retry=retry,
            timeout=timeout,
            metadata=metadata,
        )

        # Done; return the response.
        return response





try:
    _client_info = gapic_v1.client_info.ClientInfo(
        gapic_version=pkg_resources.get_distribution(
            'google-showcase',
        ).version,
    )
except pkg_resources.DistributionNotFound:
    _client_info = gapic_v1.client_info.ClientInfo()


__all__ = (
    'EchoClient',
)