Spring Boot集成Google Cloud Vision API时默认凭据不可用问题求助

报错信息 #

java.io.IOException: The Application Default Credentials are not available.
They are available if running in Google Compute Engine.
Otherwise, the environment variable GOOGLE_APPLICATION_CREDENTIALS must be defined
pointing to a file defining the credentials.
See https://developers.google.com/accounts/docs/application-default-credentials for more information.

已执行操作 #

• 创建了Google Cloud服务账号并启用了Vision API；
• 将vision-service-account.json放置在src/main/resources目录下；
• 尝试两种application.yml配置方式：
  方式一：

  spring:   
      cloud:
            gcp:
              project-id: keraa-notification  # My Google Cloud project ID
              credentials:
                location: classpath:vision-service-account.json
  

  方式二：

  google:
    cloud:
      credentials:
        path: vision-service-account.json
  

• 创建了配置类以加载凭据，但仍出现异常：

2025-03-06 14:06:20 java.io.IOException: The Application Default Credentials are not available. They are available if running in Google Compute Engine. Otherwise, the environment variable GOOGLE_APPLICATION_CREDENTIALS must be defined pointing to a file defining the credentials. See https://developers.google.com/accounts/docs/application-default-credentials for more information.
2025-03-06 14:06:20     at com.google.auth.oauth2.DefaultCredentialsProvider.getDefaultCredentials(DefaultCredentialsProvider.java:127)
2025-03-06 14:06:20     at com.google.auth.oauth2.GoogleCredentials.getApplicationDefault(GoogleCredentials.java:129)
2025-03-06 14:06:20     at com.google.auth.oauth2.GoogleCredentials.getApplicationDefault(GoogleCredentials.java:101)
2025-03-06 14:06:20     at com.google.api.gax.core.GoogleCredentialsProvider.getCredentials(GoogleCredentialsProvider.java:70)
2025-03-06 14:06:20     at com.google.api.gax.rpc.ClientContext.create(ClientContext.java:168)
2025-03-06 14:06:20     at com.google.cloud.vision.v1.stub.GrpcImageAnnotatorStub.create(GrpcImageAnnotatorStub.java:115)
2025-03-06 14:06:20     at com.google.cloud.vision.v1.stub.ImageAnnotatorStubSettings.createStub(ImageAnnotatorStubSettings.java:163)
2025-03-06 14:06:20     at com.google.cloud.vision.v1.ImageAnnotatorClient.<init>(ImageAnnotatorClient.java:160)
2025-03-06 14:06:20     at com.google.cloud.vision.v1.ImageAnnotatorClient.create(ImageAnnotatorClient.java:142)
2025-03-06 14:06:20     at com.google.cloud.vision.v1.ImageAnnotatorClient.create(ImageAnnotatorClient.java:133)
2025-03-06 14:06:20     at com.keraa.api.service.ImageModerationService.isImageSafe(ImageModerationService.java:21)
2025-03-06 14:06:20     at com.keraa.api.web.rest.ProductResource.createProduct(ProductResource.java:116)

1. 确认依赖是否正确引入 #

如果使用Spring Cloud GCP Starter，确保pom.xml中引入正确依赖：

<dependency>
    <groupId>com.google.cloud</groupId>
    <artifactId>spring-cloud-gcp-starter-vision</artifactId>
</dependency>

若直接使用Google Cloud Vision原生客户端，需确保依赖正确，此时Spring Cloud GCP配置不会自动生效，需手动加载凭据。

2. 确保Spring Cloud GCP配置生效 #

使用Spring Cloud GCP Starter时，application.yml正确配置如下：

spring:
  cloud:
    gcp:
      project-id: keraa-notification
      credentials:
        location: classpath:vision-service-account.json

同时检查打包后的target/classes目录下是否存在vision-service-account.json，确保文件被正确加载。

3. 手动加载凭据（原生客户端方式） #

直接使用ImageAnnotatorClient时，绕过默认凭据提供者，手动加载指定文件：

import com.google.cloud.vision.v1.ImageAnnotatorClient;
import com.google.cloud.vision.v1.ImageAnnotatorSettings;
import com.google.auth.oauth2.GoogleCredentials;
import org.springframework.core.io.ClassPathResource;

// 在服务类中初始化客户端
public ImageAnnotatorClient createImageAnnotatorClient() throws IOException {
    GoogleCredentials credentials = GoogleCredentials.fromStream(
            new ClassPathResource("vision-service-account.json").getInputStream());
    ImageAnnotatorSettings settings = ImageAnnotatorSettings.newBuilder()
            .setCredentialsProvider(() -> credentials)
            .build();
    return ImageAnnotatorClient.create(settings);
}

4. 检查环境变量冲突 #

若系统中存在GOOGLE_APPLICATION_CREDENTIALS环境变量，会覆盖配置文件设置，可暂时移除该变量，或确保其指向正确的文件路径。

5. 正确编写自定义配置类 #

若使用自定义配置类，确保能正确加载凭据并注入客户端：

import com.google.cloud.vision.v1.ImageAnnotatorClient;
import com.google.cloud.vision.v1.ImageAnnotatorSettings;
import com.google.auth.oauth2.GoogleCredentials;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.ClassPathResource;

import java.io.IOException;

@Configuration
public class GoogleVisionConfig {

    @Bean
    public ImageAnnotatorClient imageAnnotatorClient() throws IOException {
        GoogleCredentials credentials = GoogleCredentials.fromStream(
                new ClassPathResource("vision-service-account.json").getInputStream());
        ImageAnnotatorSettings settings = ImageAnnotatorSettings.newBuilder()
                .setCredentialsProvider(() -> credentials)
                .build();
        return ImageAnnotatorClient.create(settings);
    }
}

之后在服务类中注入ImageAnnotatorClient即可使用。

内容的提问来源于stack exchange，提问作者Charfeddine Mohamed Ali