检测语言（高级版）

本文档介绍了如何使用 Cloud Translation 高级版检测字符串的语言。

准备工作

在开始使用 Cloud Translation API 之前，您必须具有启用了 Cloud Translation API 的项目，并且必须具有适当的凭据。您还可以安装常用编程语言的客户端库，以便调用 API。如需了解详情，请参阅设置页面。

检测文本字符串的语言

要检测文本字符串的语言，使用以下格式的网址发送 HTTP 请求即可：

https://translation.googleapis.com/v3/projects/PROJECT_NUMBER_OR_ID/locations/global:detectLanguage

检测单个字符串的语言

REST

要检测部分文本的语言，请发出 POST 请求并提供相应的请求正文。下面显示了使用 curl 和 PowerShell 的 POST 请求的示例。该示例针对通过 Google Cloud CLI 为项目设置的服务账号使用访问令牌。如需了解有关安装 Google Cloud CLI、使用服务账号设置项目以及获取访问令牌的说明，请参阅设置页面。

在使用任何请求数据之前，请先进行以下替换：

PROJECT_NUMBER_OR_ID：您的 Google Cloud 项目的数字或字母数字 ID

HTTP 方法和网址：

POST https://translation.googleapis.com/v3/projects/PROJECT_NUMBER_OR_ID/locations/global:detectLanguage

请求 JSON 正文：

{
   "content":"Доктор Ватсон, иди сюда!"
}

如需发送您的请求，请展开以下选项之一：

curl（Linux、macOS 或 Cloud Shell）

注意：以下命令假定您已使用您的用户账号通过运行 gcloud init 或 gcloud auth login 登录 gcloud CLI，或者使用了 Cloud Shell，这会使您自动登录 gcloud CLI。您可以运行 gcloud auth list 来检查当前活跃的账号。

将请求正文保存在名为 request.json 的文件中，然后执行以下命令：

curl -X POST \
     -H "Authorization: Bearer $(gcloud auth print-access-token)" \
     -H "x-goog-user-project: PROJECT_NUMBER_OR_ID" \
     -H "Content-Type: application/json; charset=utf-8" \
     -d @request.json \
     "https://translation.googleapis.com/v3/projects/PROJECT_NUMBER_OR_ID/locations/global:detectLanguage"

PowerShell (Windows)

注意：以下命令假定您已使用您的用户账号通过运行 gcloud init 或 gcloud auth login 登录 gcloud CLI。您可以运行 gcloud auth list 来检查当前活跃的账号。

将请求正文保存在名为 request.json 的文件中，然后执行以下命令：

$cred = gcloud auth print-access-token
$headers = @{ "Authorization" = "Bearer $cred"; "x-goog-user-project" = "PROJECT_NUMBER_OR_ID" }

Invoke-WebRequest `
    -Method POST `
    -Headers $headers `
    -ContentType: "application/json; charset=utf-8" `
    -InFile request.json `
    -Uri "https://translation.googleapis.com/v3/projects/PROJECT_NUMBER_OR_ID/locations/global:detectLanguage" | Select-Object -Expand Content

您应该收到类似以下内容的 JSON 响应：

{
  "languages": [
    {
      "languageCode": "ru",
      "confidence": 1
    }
  ]
}

在响应中，languageCode 提供检测到的语言的代码。confidence 的范围从 0 到 1。1 表示置信度为 100%。

Go

试用此示例之前，请按照 Cloud Translation 快速入门：使用客户端库中的 Go 设置说明进行操作。如需了解详情，请参阅 Cloud Translation Go API 参考文档。

如需向 Cloud Translation 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

import (
	"context"
	"fmt"
	"io"

	translate "cloud.google.com/go/translate/apiv3"
	"cloud.google.com/go/translate/apiv3/translatepb"
)

// detectLanguage detects the language of a text string.
func detectLanguage(w io.Writer, projectID string, text string) error {
	// projectID := "my-project-id"
	// text := "Hello, world!"

	ctx := context.Background()
	client, err := translate.NewTranslationClient(ctx)
	if err != nil {
		return fmt.Errorf("NewTranslationClient: %w", err)
	}
	defer client.Close()

	req := &translatepb.DetectLanguageRequest{
		Parent:   fmt.Sprintf("projects/%s/locations/global", projectID),
		MimeType: "text/plain", // Mime types: "text/plain", "text/html"
		Source: &translatepb.DetectLanguageRequest_Content{
			Content: text,
		},
	}

	resp, err := client.DetectLanguage(ctx, req)
	if err != nil {
		return fmt.Errorf("DetectLanguage: %w", err)
	}

	// Display list of detected languages sorted by detection confidence.
	// The most probable language is first.
	for _, language := range resp.GetLanguages() {
		// The language detected.
		fmt.Fprintf(w, "Language code: %v\n", language.GetLanguageCode())
		// Confidence of detection result for this language.
		fmt.Fprintf(w, "Confidence: %v\n", language.GetConfidence())
	}

	return nil
}

Java

试用此示例之前，请按照 Cloud Translation 快速入门：使用客户端库中的 Java 设置说明进行操作。如需了解详情，请参阅 Cloud Translation Java API 参考文档。

如需向 Cloud Translation 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

import com.google.cloud.translate.v3.DetectLanguageRequest;
import com.google.cloud.translate.v3.DetectLanguageResponse;
import com.google.cloud.translate.v3.DetectedLanguage;
import com.google.cloud.translate.v3.LocationName;
import com.google.cloud.translate.v3.TranslationServiceClient;
import java.io.IOException;

public class DetectLanguage {

  public static void detectLanguage() throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    String projectId = "YOUR-PROJECT-ID";
    String text = "your-text";

    detectLanguage(projectId, text);
  }

  // Detecting the language of a text string
  public static void detectLanguage(String projectId, String text) throws IOException {

    // 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.
    try (TranslationServiceClient client = TranslationServiceClient.create()) {
      // Supported Locations: `global`, [glossary location], or [model location]
      // Glossaries must be hosted in `us-central1`
      // Custom Models must use the same location as your model. (us-central1)
      LocationName parent = LocationName.of(projectId, "global");

      // Supported Mime Types: https://cloud.google.com/translate/docs/supported-formats
      DetectLanguageRequest request =
          DetectLanguageRequest.newBuilder()
              .setParent(parent.toString())
              .setMimeType("text/plain")
              .setContent(text)
              .build();

      DetectLanguageResponse response = client.detectLanguage(request);

      // Display list of detected languages sorted by detection confidence.
      // The most probable language is first.
      for (DetectedLanguage language : response.getLanguagesList()) {
        // The language detected
        System.out.printf("Language code: %s\n", language.getLanguageCode());
        // Confidence of detection result for this language
        System.out.printf("Confidence: %s\n", language.getConfidence());
      }
    }
  }
}

Node.js

试用此示例之前，请按照 Cloud Translation 快速入门：使用客户端库中的 Node.js 设置说明进行操作。如需了解详情，请参阅 Cloud Translation Node.js API 参考文档。

如需向 Cloud Translation 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

/**
 * TODO(developer): Uncomment these variables before running the sample.
 */
// const projectId = 'YOUR_PROJECT_ID';
// const location = 'global';
// const text = 'text to translate';

// Imports the Google Cloud Translation library
const {TranslationServiceClient} = require('@google-cloud/translate');

// Instantiates a client
const translationClient = new TranslationServiceClient();

async function detectLanguage() {
  // Construct request
  const request = {
    parent: `projects/${projectId}/locations/${location}`,
    content: text,
  };

  // Run request
  const [response] = await translationClient.detectLanguage(request);

  console.log('Detected Languages:');
  for (const language of response.languages) {
    console.log(`Language Code: ${language.languageCode}`);
    console.log(`Confidence: ${language.confidence}`);
  }
}

detectLanguage();

Python

试用此示例之前，请按照 Cloud Translation 快速入门：使用客户端库中的 Python 设置说明进行操作。如需了解详情，请参阅 Cloud Translation Python API 参考文档。

如需向 Cloud Translation 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

from google.cloud import translate

def detect_language(
    project_id: str = "YOUR_PROJECT_ID",
) -> translate.DetectLanguageResponse:
    """Detecting the language of a text string.

    Args:
        project_id: The GCP project ID.

    Returns:
        The detected language of the text.
    """
    client = translate.TranslationServiceClient()

    location = "global"

    parent = f"projects/{project_id}/locations/{location}"

    # Detail on supported types can be found here:
    # https://cloud.google.com/translate/docs/supported-formats
    response = client.detect_language(
        content="Hello, world!",
        parent=parent,
        mime_type="text/plain",  # mime types: text/plain, text/html
    )

    # Display list of detected languages sorted by detection confidence.
    # The most probable language is first.
    for language in response.languages:
        # The language detected
        print(f"Language code: {language.language_code}")
        # Confidence of detection result for this language
        print(f"Confidence: {language.confidence}")

    return response

其他语言

C#：请按照客户端库页面上的 C# 设置说明操作，然后访问 .NET 版 Cloud Translation 参考文档。

PHP：请按照客户端库页面上的 PHP 设置说明操作，然后访问 PHP 版 Cloud Translation 参考文档。

Ruby：请按照客户端库页面上的 Ruby 设置说明操作，然后访问 Ruby 版 Cloud Translation 参考文档。

其他资源

如需有关解决常见问题或错误的帮助，请参阅问题排查页面。