Document AI 客户端库

本页面介绍了如何开始使用 Document AI API 的 Cloud 客户端库。通过客户端库,您可以更轻松地使用支持的语言访问Google Cloud API。虽然您可以通过向服务器发出原始请求来直接使用Google Cloud API,但客户端库可实现简化,从而显著减少您需要编写的代码量。

请参阅客户端库说明,详细了解 Cloud 客户端库和旧版 Google API 客户端库。

安装客户端库

C++

如需详细了解此客户端库的要求和安装依赖项,请参阅设置 C++ 开发环境

C#

Install-Package Google.Cloud.DocumentAI.V1 -Pre

如需了解详情,请参阅设置 C# 开发环境

Go

go get cloud.google.com/go/documentai

如需了解详情,请参阅设置 Go 开发环境

Java

If you are using Maven, add the following to your pom.xml file. For more information about BOMs, see The Google Cloud Platform Libraries BOM.

<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>com.google.cloud</groupId>
      <artifactId>libraries-bom</artifactId>
      <version>26.61.0</version>
      <type>pom</type>
      <scope>import</scope>
    </dependency>
  </dependencies>
</dependencyManagement>

<dependencies>
  <dependency>
    <groupId>com.google.cloud</groupId>
    <artifactId>google-cloud-document-ai</artifactId>
  </dependency>
</dependencies>

If you are using Gradle, add the following to your dependencies:

implementation 'com.google.cloud:google-cloud-document-ai:2.71.0'

If you are using sbt, add the following to your dependencies:

libraryDependencies += "com.google.cloud" % "google-cloud-document-ai" % "2.71.0"

If you're using Visual Studio Code, IntelliJ, or Eclipse, you can add client libraries to your project using the following IDE plugins:

The plugins provide additional functionality, such as key management for service accounts. Refer to each plugin's documentation for details.

如需了解详情,请参阅设置 Java 开发环境

Node.js

npm install @google-cloud/documentai

如需了解详情,请参阅设置 Node.js 开发环境

PHP

composer require google/cloud-document-ai

如需了解详情,请参阅在 Google Cloud 上使用 PHP

Python

pip install --upgrade google-cloud-documentai

如需了解详情,请参阅设置 Python 开发环境

Ruby

gem install google-cloud-document_ai

如需了解详情,请参阅设置 Ruby 开发环境

设置身份验证

为了对 Google Cloud API 的调用进行身份验证,客户端库支持应用默认凭据 (ADC);这些库会在一组指定的位置查找凭据,并使用这些凭据对发送到 API 的请求进行身份验证。借助 ADC,您可以在各种环境(例如本地开发或生产环境)中为您的应用提供凭据,而无需修改应用代码。

对于生产环境,设置 ADC 的方式取决于服务和上下文。如需了解详情,请参阅设置应用默认凭据

对于本地开发环境,您可以使用与您的 Google 账号关联的凭据设置 ADC:

  1. After installing the Google Cloud CLI, initialize it by running the following command:

    gcloud init

    If you're using an external identity provider (IdP), you must first sign in to the gcloud CLI with your federated identity.

  2. If you're using a local shell, then create local authentication credentials for your user account:

    gcloud auth application-default login

    You don't need to do this if you're using Cloud Shell.

    If an authentication error is returned, and you are using an external identity provider (IdP), confirm that you have signed in to the gcloud CLI with your federated identity.

    登录屏幕随即出现。在您登录后,您的凭据会存储在 ADC 使用的本地凭据文件中。

使用客户端库

以下示例展示了如何使用客户端库。

C++


#include "google/cloud/documentai/v1/document_processor_client.h"
#include "google/cloud/location.h"
#include <fstream>
#include <iostream>
#include <string>

int main(int argc, char* argv[]) try {
  if (argc != 5) {
    std::cerr << "Usage: " << argv[0]
              << " project-id location-id processor-id filename (PDF only)\n";
    return 1;
  }

  std::string const location_id = argv[2];
  if (location_id != "us" && location_id != "eu") {
    std::cerr << "location-id must be either 'us' or 'eu'\n";
    return 1;
  }
  auto const location = google::cloud::Location(argv[1], location_id);

  namespace documentai = ::google::cloud::documentai_v1;
  auto client = documentai::DocumentProcessorServiceClient(
      documentai::MakeDocumentProcessorServiceConnection(
          location.location_id()));

  google::cloud::documentai::v1::ProcessRequest req;
  req.set_name(location.FullName() + "/processors/" + argv[3]);
  req.set_skip_human_review(true);
  auto& doc = *req.mutable_raw_document();
  doc.set_mime_type("application/pdf");
  std::ifstream is(argv[4]);
  doc.set_content(std::string{std::istreambuf_iterator<char>(is), {}});

  auto resp = client.ProcessDocument(std::move(req));
  if (!resp) throw std::move(resp).status();
  std::cout << resp->document().text() << "\n";

  return 0;
} catch (google::cloud::Status const& status) {
  std::cerr << "google::cloud::Status thrown: " << status << "\n";
  return 1;
}

C#


using Google.Cloud.DocumentAI.V1;
using Google.Protobuf;
using System;
using System.IO;

public class QuickstartSample
{
    public Document Quickstart(
        string projectId = "your-project-id",
        string locationId = "your-processor-location",
        string processorId = "your-processor-id",
        string localPath = "my-local-path/my-file-name",
        string mimeType = "application/pdf"
    )
    {
        // Create client
        var client = new DocumentProcessorServiceClientBuilder
        {
            Endpoint = $"{locationId}-documentai.googleapis.com"
        }.Build();

        // Read in local file
        using var fileStream = File.OpenRead(localPath);
        var rawDocument = new RawDocument
        {
            Content = ByteString.FromStream(fileStream),
            MimeType = mimeType
        };

        // Initialize request argument(s)
        var request = new ProcessRequest
        {
            Name = ProcessorName.FromProjectLocationProcessor(projectId, locationId, processorId).ToString(),
            RawDocument = rawDocument
        };

        // Make the request
        var response = client.ProcessDocument(request);

        var document = response.Document;
        Console.WriteLine(document.Text);
        return document;
    }
}

Go

import (
	"context"
	"flag"
	"fmt"
	"os"

	documentai "cloud.google.com/go/documentai/apiv1"
	"cloud.google.com/go/documentai/apiv1/documentaipb"
	"google.golang.org/api/option"
)

func main() {
	projectID := flag.String("project_id", "PROJECT_ID", "Cloud Project ID")
	location := flag.String("location", "us", "The Processor location")
	// Create a Processor before running sample
	processorID := flag.String("processor_id", "aaaaaaaa", "The Processor ID")
	filePath := flag.String("file_path", "invoice.pdf", "The path to the file to parse")
	mimeType := flag.String("mime_type", "application/pdf", "The mimeType of the file")
	flag.Parse()

	ctx := context.Background()

	endpoint := fmt.Sprintf("%s-documentai.googleapis.com:443", *location)
	client, err := documentai.NewDocumentProcessorClient(ctx, option.WithEndpoint(endpoint))
	if err != nil {
		fmt.Println(fmt.Errorf("error creating Document AI client: %w", err))
	}
	defer client.Close()

	// Open local file.
	data, err := os.ReadFile(*filePath)
	if err != nil {
		fmt.Println(fmt.Errorf("os.ReadFile: %w", err))
	}

	req := &documentaipb.ProcessRequest{
		Name: fmt.Sprintf("projects/%s/locations/%s/processors/%s", *projectID, *location, *processorID),
		Source: &documentaipb.ProcessRequest_RawDocument{
			RawDocument: &documentaipb.RawDocument{
				Content:  data,
				MimeType: *mimeType,
			},
		},
	}
	resp, err := client.ProcessDocument(ctx, req)
	if err != nil {
		fmt.Println(fmt.Errorf("processDocument: %w", err))
	}

	// Handle the results.
	document := resp.GetDocument()
	fmt.Printf("Document Text: %s", document.GetText())
}

Java

import com.google.cloud.documentai.v1.Document;
import com.google.cloud.documentai.v1.DocumentProcessorServiceClient;
import com.google.cloud.documentai.v1.DocumentProcessorServiceSettings;
import com.google.cloud.documentai.v1.ProcessRequest;
import com.google.cloud.documentai.v1.ProcessResponse;
import com.google.cloud.documentai.v1.RawDocument;
import com.google.protobuf.ByteString;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeoutException;

public class QuickStart {
  public static void main(String[] args)
      throws IOException, InterruptedException, ExecutionException, TimeoutException {
    // TODO(developer): Replace these variables before running the sample.
    String projectId = "your-project-id";
    String location = "your-project-location"; // Format is "us" or "eu".
    String processorId = "your-processor-id";
    String filePath = "path/to/input/file.pdf";
    quickStart(projectId, location, processorId, filePath);
  }

  public static void quickStart(
      String projectId, String location, String processorId, String filePath)
      throws IOException, InterruptedException, ExecutionException, TimeoutException {
    // Initialize client that will be used to send requests. This client only needs
    // to be created
    // once, and can be reused for multiple requests. After completing all of your
    // requests, call
    // the "close" method on the client to safely clean up any remaining background
    // resources.
    String endpoint = String.format("%s-documentai.googleapis.com:443", location);
    DocumentProcessorServiceSettings settings =
        DocumentProcessorServiceSettings.newBuilder().setEndpoint(endpoint).build();
    try (DocumentProcessorServiceClient client = DocumentProcessorServiceClient.create(settings)) {
      // The full resource name of the processor, e.g.:
      // projects/project-id/locations/location/processor/processor-id
      // You must create new processors in the Cloud Console first
      String name =
          String.format("projects/%s/locations/%s/processors/%s", projectId, location, processorId);

      // Read the file.
      byte[] imageFileData = Files.readAllBytes(Paths.get(filePath));

      // Convert the image data to a Buffer and base64 encode it.
      ByteString content = ByteString.copyFrom(imageFileData);

      RawDocument document =
          RawDocument.newBuilder().setContent(content).setMimeType("application/pdf").build();

      // Configure the process request.
      ProcessRequest request =
          ProcessRequest.newBuilder().setName(name).setRawDocument(document).build();

      // Recognizes text entities in the PDF document
      ProcessResponse result = client.processDocument(request);
      Document documentResponse = result.getDocument();

      // Get all of the document text as one big string
      String text = documentResponse.getText();

      // Read the text recognition output from the processor
      System.out.println("The document contains the following paragraphs:");
      Document.Page firstPage = documentResponse.getPages(0);
      List<Document.Page.Paragraph> paragraphs = firstPage.getParagraphsList();

      for (Document.Page.Paragraph paragraph : paragraphs) {
        String paragraphText = getText(paragraph.getLayout().getTextAnchor(), text);
        System.out.printf("Paragraph text:\n%s\n", paragraphText);
      }
    }
  }

  // Extract shards from the text field
  private static String getText(Document.TextAnchor textAnchor, String text) {
    if (textAnchor.getTextSegmentsList().size() > 0) {
      int startIdx = (int) textAnchor.getTextSegments(0).getStartIndex();
      int endIdx = (int) textAnchor.getTextSegments(0).getEndIndex();
      return text.substring(startIdx, endIdx);
    }
    return "[NO TEXT]";
  }
}

Node.js

/**
 * TODO(developer): Uncomment these variables before running the sample.
 */
// const projectId = 'YOUR_PROJECT_ID';
// const location = 'YOUR_PROJECT_LOCATION'; // Format is 'us' or 'eu'
// const processorId = 'YOUR_PROCESSOR_ID'; // Create processor in Cloud Console
// const filePath = '/path/to/local/pdf';

const {DocumentProcessorServiceClient} =
  require('@google-cloud/documentai').v1;

// Instantiates a client
// apiEndpoint regions available: eu-documentai.googleapis.com, us-documentai.googleapis.com (Required if using eu based processor)
// const client = new DocumentProcessorServiceClient({apiEndpoint: 'eu-documentai.googleapis.com'});
const client = new DocumentProcessorServiceClient();

async function quickstart() {
  // The full resource name of the processor, e.g.:
  // projects/project-id/locations/location/processor/processor-id
  // You must create new processors in the Cloud Console first
  const name = `projects/${projectId}/locations/${location}/processors/${processorId}`;

  // Read the file into memory.
  const fs = require('fs').promises;
  const imageFile = await fs.readFile(filePath);

  // Convert the image data to a Buffer and base64 encode it.
  const encodedImage = Buffer.from(imageFile).toString('base64');

  const request = {
    name,
    rawDocument: {
      content: encodedImage,
      mimeType: 'application/pdf',
    },
  };

  // Recognizes text entities in the PDF document
  const [result] = await client.processDocument(request);
  const {document} = result;

  // Get all of the document text as one big string
  const {text} = document;

  // Extract shards from the text field
  const getText = textAnchor => {
    if (!textAnchor.textSegments || textAnchor.textSegments.length === 0) {
      return '';
    }

    // First shard in document doesn't have startIndex property
    const startIndex = textAnchor.textSegments[0].startIndex || 0;
    const endIndex = textAnchor.textSegments[0].endIndex;

    return text.substring(startIndex, endIndex);
  };

  // Read the text recognition output from the processor
  console.log('The document contains the following paragraphs:');
  const [page1] = document.pages;
  const {paragraphs} = page1;

  for (const paragraph of paragraphs) {
    const paragraphText = getText(paragraph.layout.textAnchor);
    console.log(`Paragraph text:\n${paragraphText}`);
  }
}

PHP

# Include the autoloader for libraries installed with Composer.
require __DIR__ . '/vendor/autoload.php';

# Import the Google Cloud client library.
use Google\Cloud\DocumentAI\V1\Client\DocumentProcessorServiceClient;
use Google\Cloud\DocumentAI\V1\RawDocument;
use Google\Cloud\DocumentAI\V1\ProcessRequest;

# TODO(developer): Update the following lines before running the sample.
# Your Google Cloud Platform project ID.
$projectId = 'YOUR_PROJECT_ID';

# Your Processor Location.
$location = 'us';

# Your Processor ID as hexadecimal characters.
# Not to be confused with the Processor Display Name.
$processorId = 'YOUR_PROCESSOR_ID';

# Path for the file to read.
$documentPath = 'resources/invoice.pdf';

# Create Client.
$client = new DocumentProcessorServiceClient();

# Read in file.
$handle = fopen($documentPath, 'rb');
$contents = fread($handle, filesize($documentPath));
fclose($handle);

# Load file contents into a RawDocument.
$rawDocument = (new RawDocument())
    ->setContent($contents)
    ->SetMimeType('application/pdf');

# Get the Fully-qualified Processor Name.
$fullProcessorName = $client->processorName($projectId, $location, $processorId);

# Send a ProcessRequest and get a ProcessResponse.
$request = (new ProcessRequest())
    ->setName($fullProcessorName)
    ->setRawDocument($rawDocument);

$response = $client->processDocument($request);

# Show the text found in the document.
printf('Document Text: %s', $response->getDocument()->getText());

Python

from google.api_core.client_options import ClientOptions
from google.cloud import documentai_v1

# TODO(developer): Create a processor of type "OCR_PROCESSOR".

# TODO(developer): Update and uncomment these variables before running the sample.
# project_id = "MY_PROJECT_ID"

# Processor ID as hexadecimal characters.
# Not to be confused with the Processor Display Name.
# processor_id = "MY_PROCESSOR_ID"

# Processor location. For example: "us" or "eu".
# location = "MY_PROCESSOR_LOCATION"

# Path for file to process.
# file_path = "/path/to/local/pdf"

# Set `api_endpoint` if you use a location other than "us".
opts = ClientOptions(api_endpoint=f"{location}-documentai.googleapis.com")

# Initialize Document AI client.
client = documentai_v1.DocumentProcessorServiceClient(client_options=opts)

# Get the Fully-qualified Processor path.
full_processor_name = client.processor_path(project_id, location, processor_id)

# Get a Processor reference.
request = documentai_v1.GetProcessorRequest(name=full_processor_name)
processor = client.get_processor(request=request)

# `processor.name` is the full resource name of the processor.
# For example: `projects/{project_id}/locations/{location}/processors/{processor_id}`
print(f"Processor Name: {processor.name}")

# Read the file into memory.
with open(file_path, "rb") as image:
    image_content = image.read()

# Load binary data.
# For supported MIME types, refer to https://cloud.google.com/document-ai/docs/file-types
raw_document = documentai_v1.RawDocument(
    content=image_content,
    mime_type="application/pdf",
)

# Send a request and get the processed document.
request = documentai_v1.ProcessRequest(name=processor.name, raw_document=raw_document)
result = client.process_document(request=request)
document = result.document

# Read the text recognition output from the processor.
# For a full list of `Document` object attributes, reference this page:
# https://cloud.google.com/document-ai/docs/reference/rest/v1/Document
print("The document contains the following text:")
print(document.text)

Ruby

require "google/cloud/document_ai/v1"

##
# Document AI quickstart
#
# @param project_id [String] Your Google Cloud project (e.g. "my-project")
# @param location_id [String] Your Processor Location (e.g. "us")
# @param processor_id [String] Your Processor ID (e.g. "a14dae8f043b60bd")
# @param file_path [String] Path to Local File (e.g. "invoice.pdf")
# @param mime_type [String] Refer to https://cloud.google.com/document-ai/docs/file-types (e.g. "application/pdf")
#
def quickstart project_id:, location_id:, processor_id:, file_path:, mime_type:
  # Create the Document AI client.
  client = ::Google::Cloud::DocumentAI::V1::DocumentProcessorService::Client.new do |config|
    config.endpoint = "#{location_id}-documentai.googleapis.com"
  end

  # Build the resource name from the project.
  name = client.processor_path(
    project: project_id,
    location: location_id,
    processor: processor_id
  )

  # Read the bytes into memory
  content = File.binread file_path

  # Create request
  request = Google::Cloud::DocumentAI::V1::ProcessRequest.new(
    skip_human_review: true,
    name: name,
    raw_document: {
      content: content,
      mime_type: mime_type
    }
  )

  # Process document
  response = client.process_document request

  # Handle response
  puts response.document.text
end

其他资源

C++

以下列表包含与 C++ 版客户端库相关的更多资源的链接:

C#

以下列表包含与 C# 版客户端库相关的更多资源的链接:

Go

以下列表包含与 Go 版客户端库相关的更多资源的链接:

Java

以下列表包含与 Java 版客户端库相关的更多资源的链接:

Node.js

以下列表包含与 Node.js 版客户端库相关的更多资源的链接:

PHP

以下列表包含与 PHP 版客户端库相关的更多资源的链接:

Python

以下列表包含与 Python 版客户端库相关的更多资源的链接:

Ruby

以下列表包含与 Ruby 版客户端库相关的更多资源的链接: