client.py

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

# Copyright 2020 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
import re
from typing import Callable, 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.cloud.documentai_v1beta2.types import document
from google.cloud.documentai_v1beta2.types import document_understanding
from google.rpc import status_pb2 as status  # type: ignore

from .transports.base import DocumentUnderstandingServiceTransport
from .transports.grpc import DocumentUnderstandingServiceGrpcTransport


class DocumentUnderstandingServiceClientMeta(type):
    """Metaclass for the DocumentUnderstandingService 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[DocumentUnderstandingServiceTransport]]
    _transport_registry["grpc"] = DocumentUnderstandingServiceGrpcTransport

    def get_transport_class(
        cls, label: str = None
    ) -> Type[DocumentUnderstandingServiceTransport]:
        """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 DocumentUnderstandingServiceClient(
    metaclass=DocumentUnderstandingServiceClientMeta
):
    """Service to parse structured information from unstructured or
    semi-structured documents using state-of-the-art Google AI such
    as natural language, computer vision, and translation.
    """

    @staticmethod
    def _get_default_mtls_endpoint(api_endpoint):
        """Convert api endpoint to mTLS endpoint.
        Convert "*.sandbox.googleapis.com" and "*.googleapis.com" to
        "*.mtls.sandbox.googleapis.com" and "*.mtls.googleapis.com" respectively.
        Args:
            api_endpoint (Optional[str]): the api endpoint to convert.
        Returns:
            str: converted mTLS api endpoint.
        """
        if not api_endpoint:
            return api_endpoint

        mtls_endpoint_re = re.compile(
            r"(?P<name>[^.]+)(?P<mtls>\.mtls)?(?P<sandbox>\.sandbox)?(?P<googledomain>\.googleapis\.com)?"
        )

        m = mtls_endpoint_re.match(api_endpoint)
        name, mtls, sandbox, googledomain = m.groups()
        if mtls or not googledomain:
            return api_endpoint

        if sandbox:
            return api_endpoint.replace(
                "sandbox.googleapis.com", "mtls.sandbox.googleapis.com"
            )

        return api_endpoint.replace(".googleapis.com", ".mtls.googleapis.com")

    DEFAULT_ENDPOINT = "us-documentai.googleapis.com"
    DEFAULT_MTLS_ENDPOINT = _get_default_mtls_endpoint.__func__(  # type: ignore
        DEFAULT_ENDPOINT
    )

    @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, DocumentUnderstandingServiceTransport] = None,
        client_options: ClientOptions = None,
    ) -> None:
        """Instantiate the document understanding service 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, ~.DocumentUnderstandingServiceTransport]): The
                transport to use. If set to None, a transport is chosen
                automatically.
            client_options (ClientOptions): Custom options for the client.
                (1) The ``api_endpoint`` property can be used to override the
                default endpoint provided by the client.
                (2) If ``transport`` argument is None, ``client_options`` can be
                used to create a mutual TLS transport. If ``client_cert_source``
                is provided, mutual TLS transport will be created with the given
                ``api_endpoint`` or the default mTLS endpoint, and the client
                SSL credentials obtained from ``client_cert_source``.

        Raises:
            google.auth.exceptions.MutualTlsChannelError: If mutual TLS transport
                creation failed for any reason.
        """
        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, DocumentUnderstandingServiceTransport):
            # transport is a DocumentUnderstandingServiceTransport instance.
            if credentials:
                raise ValueError(
                    "When providing a transport instance, "
                    "provide its credentials directly."
                )
            self._transport = transport
        elif client_options is None or (
            client_options.api_endpoint is None
            and client_options.client_cert_source is None
        ):
            # Don't trigger mTLS if we get an empty ClientOptions.
            Transport = type(self).get_transport_class(transport)
            self._transport = Transport(
                credentials=credentials, host=self.DEFAULT_ENDPOINT
            )
        else:
            # We have a non-empty ClientOptions. If client_cert_source is
            # provided, trigger mTLS with user provided endpoint or the default
            # mTLS endpoint.
            if client_options.client_cert_source:
                api_mtls_endpoint = (
                    client_options.api_endpoint
                    if client_options.api_endpoint
                    else self.DEFAULT_MTLS_ENDPOINT
                )
            else:
                api_mtls_endpoint = None

            api_endpoint = (
                client_options.api_endpoint
                if client_options.api_endpoint
                else self.DEFAULT_ENDPOINT
            )

            self._transport = DocumentUnderstandingServiceGrpcTransport(
                credentials=credentials,
                host=api_endpoint,
                api_mtls_endpoint=api_mtls_endpoint,
                client_cert_source=client_options.client_cert_source,
            )

    def batch_process_documents(
        self,
        request: document_understanding.BatchProcessDocumentsRequest = None,
        *,
        requests: Sequence[document_understanding.ProcessDocumentRequest] = None,
        retry: retries.Retry = gapic_v1.method.DEFAULT,
        timeout: float = None,
        metadata: Sequence[Tuple[str, str]] = (),
    ) -> operation.Operation:
        r"""LRO endpoint to batch process many documents. The output is
        written to Cloud Storage as JSON in the [Document] format.

        Args:
            request (:class:`~.document_understanding.BatchProcessDocumentsRequest`):
                The request object. Request to batch process documents
                as an asynchronous operation. The output is written to
                Cloud Storage as JSON in the [Document] format.
            requests (:class:`Sequence[~.document_understanding.ProcessDocumentRequest]`):
                Required. Individual requests for
                each document.
                This corresponds to the ``requests`` 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:
            ~.operation.Operation:
                An object representing a long-running operation.

                The result type for the operation will be
                :class:``~.document_understanding.BatchProcessDocumentsResponse``:
                Response to an batch document processing request. This
                is returned in the LRO Operation after the operation is
                complete.

        """
        # 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([requests]):
            raise ValueError(
                "If the `request` argument is set, then none of "
                "the individual field arguments should be set."
            )

        request = document_understanding.BatchProcessDocumentsRequest(request)

        # If we have keyword arguments corresponding to fields on the
        # request, apply these.

        if requests is not None:
            request.requests = requests

        # Wrap the RPC method; this adds retry and timeout information,
        # and friendly error handling.
        rpc = gapic_v1.method.wrap_method(
            self._transport.batch_process_documents,
            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,
            document_understanding.BatchProcessDocumentsResponse,
            metadata_type=document_understanding.OperationMetadata,
        )

        # Done; return the response.
        return response

    def process_document(
        self,
        request: document_understanding.ProcessDocumentRequest = None,
        *,
        retry: retries.Retry = gapic_v1.method.DEFAULT,
        timeout: float = None,
        metadata: Sequence[Tuple[str, str]] = (),
    ) -> document.Document:
        r"""Processes a single document.

        Args:
            request (:class:`~.document_understanding.ProcessDocumentRequest`):
                The request object. Request to process one document.

            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:
            ~.document.Document:
                Document represents the canonical
                document resource in Document
                Understanding AI. It is an interchange
                format that provides insights into
                documents and allows for collaboration
                between users and Document Understanding
                AI to iterate and optimize for quality.

        """
        # Create or coerce a protobuf request object.

        request = document_understanding.ProcessDocumentRequest(request)

        # Wrap the RPC method; this adds retry and timeout information,
        # and friendly error handling.
        rpc = gapic_v1.method.wrap_method(
            self._transport.process_document,
            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-cloud-documentai").version
    )
except pkg_resources.DistributionNotFound:
    _client_info = gapic_v1.client_info.ClientInfo()


__all__ = ("DocumentUnderstandingServiceClient",)